Moto Guzzi Loop Frames - Electrical components

Alternator conversion

• Print this section

If you are just running stock electrics, you will find the 300 watt loop frame generator to be more than adequate. However, if you start adding lights, heated clothing, etc., you will find that the power supply is not limitless. Loop frame alternator conversions have been around for a long time in various formats. Here are a few examples.

Bob Nolan / Greg Field alternator conversion kit

Greg Field and Bob Nolan put a loop frame alternator conversion kit together and have made it available. I have purchased and installed the kit. It is top notch in every respect and very well done. I am very pleased with how it fits and the power output is fantastic, even at idle. I have nothing but good things to say about this kit. If you are interested in purchasing it, please contact Greg Field directly at greguzzi>at<comcast.net. Here are some words from Greg Field describing the conversion:

Bob Nolan and I are selling a complete kit to replace the 300w generator on your V700, Ambassador, V7 Special, or Eldorado with a 600w Nippon Denso alternator.

The kit includes a new ND 600-watt alternator, a mounting bracket that replaces the generator bracket, and all wiring necessary to make it integrate with the stock wiring. It all bolts right on and requires no changes of any kind to stock parts, not even the generator-belt cover or stock wiring connectors.

The alternator is brand new and covered by an ND warranty. It has an internal regulator. Two wires are necessary to run it: one to the battery and another that connects to switched power. A third wire is optional and goes to the charging light on your dash.

The bracket is welded of 1/4-inch steel. It mounts to the two stock mounting bolts to the engine block. We also added a strap that bolts to the front bolt of the distributor. It will be painted. Bob and I will warranty the bracket as follows: If it cracks or breaks within a year, we'll fix or replace it.

The wiring harness consists of two wires and an adaptor connector. One wire carries the generated electricity to the battery. Another short wire connects to switched power at the coil. The adaptor connector allows attachment of the stock wiring for the generator light on your dash.

Installation notes

Installation is simple and straightforward. The included instructions are great. Do take the time to install studs to secure the bracket to the block (rather than Guzzi's original bolts).

On my maiden voyage I had trouble with the connector to the idiot light coming loose. The first time I thought perhaps I had failed to connect it. The second time I knew something was up and I gave the female spade connector a little squeeze with my pliers from the toolkit. It still wiggled loose. I solved the problem by replacing the adapter with a simple female spade connector - no more disconnects for 1,000 + miles.

Maynard's alternator conversion

I took these pictures of the alternator conversion Maynard (Neil Hemenway) did on his Eldorado at the MGNOC 2004 National Rally. I hope they prove useful to those interested in such a transformation.

• Back to top

Batteries

• Print this section

Dimensions

Here is the biggest you can go and still use the stock hold down bracket (and fit the side covers):

• 5 7/16" wide (front to back in the motorcycle)
• 9 3/8" long (side to side in the motorcycle)
• 7 1/2" tall (seems that a battery 8.69" tall will fit...I will update this value once I inspect Cam's install at the 2007 Virginia Rally)

Garden tractor batteries

I used to be a proponent of the very inexpensive lawn and garden tractor batteries such as the Interstate SP30R Battery with 290 CA and 230 CCA or the EverStart U1P-7 garden tractor sized battery with 350 CA and 275 CCA available from Wal-Mart. However, these batteries have low cranking power and vent corrosive gases. I was never completely satisfied with them. But, if you are on a budget, these will definitely get the job done inexpensively.

Drycell batteries

A great battery choice recommended by John Ulrich is the Odyssey PC 925 MJT with 380 cold cranking amps and 925 cranking amps for 5 seconds. Since it is completely sealed, it is installed on it's side and fits well in the battery tray. Battery Mart.

George Dockray was kind enough to send me a couple of photos of his PC 925 installation. He glued rubber sheet to a piece of 3/4" plywood for the base to get it out of the way of the bolt heads and base tabs.

Greg Field reports that the Odyssey PC 545 and Odyssey PC 680 batteries fit and function well.

Group 51 batteries

Charlie Mullendore recently informed me that the AC Delco 51R-60 battery fits. Here are the details:

• Cold Cranking Amperage (CCA): 450
• Cranking Amperage (CA): 530
• Length: 9.31"
• Width: 4.94"
• Height: 8.69"
• Weight: 28 pounds

Group 55 batteries

The Group 55 battery size is pretty much discontinued by everyone. If you do find one, it may be very old. My recommendation is that you do not waste your time trying to find one of these. However, I've kept the information on them below for reference.

However, based on recommendations from Robert A. Greene and Mark Etheridge of Moto Guzzi Classics, I have now chosen to use an AC Delco Group 55-6 year battery with 535 CCA. I picked one up from my local auto parts distributor. A Napa Group 55 battery may also work, but doesn't fit as well as the AC Delco.

If your local auto parts house just has to have a vehicle to look up a part, try any of the following:

• 1993 - 1995 Kia Sephia
• 1987 - 1990 Jeep Wrangler
• 1978 - 1980 Ford Thunderbird

As for installation, I was able to use the stock battery hold-down bracket and the long L-shaped bolts. I did have to modify the battery a bit, though, in several places. Along the bottom of the battery there is an extra chunk of plastic that is usually used to clamp the battery to the battery tray in cars, etc. This extra chunk got in the way of the four tabs on the battery tray. Some quick work at the bench grinder got rid of those (I just love grinding on a battery with power tools!). Also, on either long side of the top of the battery, I whittled away some extra plastic so that the hold-down bracket would fit snug. I just used a razor blade for this work. Since this is a top post battery, I found some adapters at the local parts store that worked well for mounting my ring connectors.

I am very happy with this battery. The starter cranks much faster and the lights are less susceptible to dimming with engine speed. This upgrade was well worth the extra money and minor modifications.

Follow-up: My AC Delco battery worked very well for nearly 2 years...then died. The battery was already old when I purchased it and no replacements were available. For now, I stuck my old garden tractor battery back in.

• Back to top

Battery hold down bracket for Odyssey PC925

• Print this section

After installing an Odyssey PC925L battery in my Ambassador, I wanted a well fitting hold down bracket. The stock bracket didn't work well and I did not wish to drill any additional holes in my battery tray. So, I decided to craft my own homemade battery hold down bracket. I could have welded a few pieces of steel together and that would have worked just fine. Instead, I decided to use commonly available aluminum pieces and stainless steel fasteners. A hack saw, drill, and file were all the tools needed. There are simpler designs, but this battery hold down bracket can be made by almost any loop frame owner with very basic skills, tools, and readily available materials.

A few notes:

• The flat stock I used was 1" wide and 3/16" thick.
• The L-shaped stock I used was 1" x 1" wide and 1/8" thick.
• I chose to round the exposed corners of the L-shaped aluminum pieces. I traced the corner using a socket of a size I found pleasing. I started by using a hack saw to cut the basic corner shape, then finished it up with a hand file.
• When everything was complete, I used the wire brush on my bench grinder to clean up the aluminum and give it a brushed appearance.

Disclaimer: I have not tried this bracket with the stock air box. It may extend too far forward and interfere with the stock air box. But, I think the battery could be moved rearward somewhat and provide the needed clearance. The stock battery hold down bracket had a tendency to hit the stock air box, too. I would fit a piece of rubber between the bracket and the air box to prevent damage.

Odyssey PC925 battery and hold down bracket.Odyssey PC925 battery and hold down bracket.

Hold down bracket fitted to battery.Hold down bracket fitted to battery.

View of the underneath of the front fitting portion. T-shaped aluminum stock is not readily available in most hardware stores, so I chose to use 2 L-shaped pieces. Because of this decision, the L-shaped pieces had to extend past the width of the battery to the left and the right. The use of T-shaped aluminum stock would greatly simplify construction and make the overall bracket smaller.View of the underneath of the front fitting portion. T-shaped aluminum stock is not readily available in most hardware stores, so I chose to use 2 L-shaped pieces. Because of this decision, the L-shaped pieces had to extend past the width of the battery to the left and the right. The use of T-shaped aluminum stock would greatly simplify construction and make the overall bracket smaller.

Close up view of the underneath of the rear fitting portion. The right side flat stock extends further rearward of the angle stock so as to provide a securing location for the right rear L-shaped bolt.Close up view of the underneath of the rear fitting portion. The right side flat stock extends further rearward of the angle stock so as to provide a securing location for the right rear L-shaped bolt.

Another view of the underneath of the rear fitting portion.Another view of the underneath of the rear fitting portion.

A view of the rear portion fitted to the battery. The heads of the bolts clear the shape of the battery nicely.A view of the rear portion fitted to the battery. The heads of the bolts clear the shape of the battery nicely.

View of the left side of the battery installed with the bracket in place.View of the left side of the battery installed with the bracket in place.

View of the left side L-shaped bolt in the standard position using the standard holes.View of the left side L-shaped bolt in the standard position using the standard holes.

View of the right side of the battery installed with the bracket in place.View of the right side of the battery installed with the bracket in place.

View of the right side L-shaped bolt in the reversed position using the standard holes. The L-shaped bolt can easily be installed in this reversed position by inserting it up from the bottom to the left of the drive shaft.View of the right side L-shaped bolt in the reversed position using the standard holes. The L-shaped bolt can easily be installed in this reversed position by inserting it up from the bottom to the left of the drive shaft.

A close up view of the L-shaped bolt in the reversed position on the right side.A close up view of the L-shaped bolt in the reversed position on the right side.

The speedometer cable clears the battery bracket just fine.The speedometer cable clears the battery bracket just fine.

A view of my dusty side cover in place. It clears the bracket just fine.A view of my dusty side cover in place. It clears the bracket just fine.

A close-up view of the side cover clearing the battery hold down bracket.A close-up view of the side cover clearing the battery hold down bracket.

• Back to top

Bullet terminal connections

• Print this section

Thanks to Charlie Mullendore of Antietam Classic Cycle for providing this information on the Yahoo! Loopframe_Guzzi news group.

Bullet terminals are available in two common sizes: 0.157" and 0.176". The electrical connections on the loop frames use the 0.157" sized bullet terminals.

• Back to top

Coil alternatives

• Print this section

I extracted some of this information from the old Topica Loopframe_Guzzi news group (which has now moved to Yahoo!). The epoxy-filled "Bosch Blue" is the most frequently cited alternative coil used (some report bad experiences with oil filled coils). Whichever one you choose, be sure that it has 3 Ohm resistance. A great cross-reference is any Volkswagen Beetle manufactured between 1975 and 1979 (12 volt).

• AC Delco U515 or U501 - Advance Auto
• Bosch Blue 00012 - Advance Auto
  I have been using this one on my Ambassador for several thousand miles and it has performed quite well. I chose it because it was cheap and readily available at my local store.
• Bosch Blue ZX075527P - JC Whitney
• Borg Warner E40 - Advance Auto
• Borg Warner E40P - Advance Auto
• Borg Warner E81 - Advance Auto
• GP Sorensen 245037 - Advance Auto
• Niehoff Ignition DR180 - Advance Auto
• Niehoff Ignition UN171 - Advance Auto
• Standard UC15X - Advance Auto
• Standard UF3 - Advance Auto

• Back to top

Coil information

• Print this section

Thanks to Ralf Brinkmann for sending me this information. Ralf is remembering much of this from an extract of a schoolbook. In Ralf's own words:

Some years ago with my Guzzi I changed to the blue Bosch coil - so last year I gave away all my black Bosch coils to the owner of a BMW-Isetta. I collected these coils over the years when I had air-cooled Volkswaggons - so I'm not able to measure but they all differ a little bit in size and resistance.

But I have a chart for you. The chart compares the black (E), the blue (K), and the red (KW) Bosch coil and shows how fast a modern transistor driven coil loads. In this chart the Guzzi engine would count as 3-Cyl. due to the asymetric arrangement.

The lower the the resistance of the coil the faster the coil loads up to a definite voltage line - important at high engine speed.

The limit for the breaker points is the 5A line. For this reason the red E-coil needs a fat 1.8 Ohm resistor in series connection. The resistor may be shortened by a relays while starting.

If you want more amps you must use electronic components. Modern Guzzi coils - e.g. Jackal - have less than 1.0 Ohm resistance in the primary circuit.

In combination with the breaker points the powerful 4th coil will need something like this: Steuergeraete fuer Zuendanlagen mit Unterbrecherkontakt und Fliehkraftverstellung

These breaker point driven TSZ-U (or TSZ-K) controllers do not close the primary coil circuit for a fixed angle but for a fixed max. time - maybe 4 ms - depending on the coil - in German called "automatische Schliesswinkelregelung"

I wonder if the tiny Guzzi distributor cap would survive the high voltage - maybe one day I'll ask the FIAT-500 club.

To view PDF files, you will need to download and install the free Adobe Acrobat Reader version 5.0 or higher.

NOTE: If you have trouble viewing PDF files inside your browser, try saving them to your computer (right-click the link, then choose the save option). Then, open each file directly in Adobe Acrobat Reader.

• Back to top

Coil terminal connections

• Print this section

Some loop frame coils do not have the positive and negative terminals identified with easy-to-understand symbols (such as '+' for positive and '-' for negative). Instead, the coil terminals are labeled with numbers. The terminal labeled with the number one ('1') is the negative terminal. The terminal labeled with the number fifteen ('15') is the positive terminal.

If it is not possible to read these numbers, you may want to count the male spade connector leads at each terminal. Usually, the positive terminal has two leads while the negative terminal has one lead.

• Back to top

Electricity usage by component

• Print this section

Loop frame generators are rated at 300 watts at 2400 RPM. Since this is a 12 volt system, this equates to 25 amperes (300 watts / 12 volts = 25 amperes). Or, since the charging system is usually charging at about 14 volts, the equation becomes: 300 watts / 14 volts = 21.4 amperes. In either case, we're still dealing with about 300 watts of power. Where does all this juice go?

These calculations are rough and do not take all factors or electrical components into consideration (such as resistance), so these numbers are probably a little low. They are helpful, though, even given the limitations.

Two things are immediately apparent from these numbers. First, the stock system is set up with plenty of reserve, even with the police lights (although I don't know wattage usage for components such as the radio, etc.). Second, adding high wattage bulbs quickly puts my Ambassador at the limit. When the generator cannot produce enough electricity to keep up with demand, the power will be scavenged from the battery. After a while, the battery's power will be depleted and things start getting very ugly. Initially, the lights will dim. But if the situation persists, there will not even be enough power to operate the coil, and so the ignition will start cutting out.

• Back to top

Electronic ignition - alternatives

• Print this section

I've not tried any of these alternative electronic ignitions.

• Silent Hektik
• Moto Schmitz

• Back to top

Electronic ignition - Harper's Pertronix unit

• Print this section

The purchase

Apr 04, 2004 - - I purchased the Harper's High Output Electronic Ignition kit today (it's being shipped). I will post my experiences with this system here from installation to performance. Since I wasn't able to find any information on the web about other user's experiences before I spent my USD $330.00, I'll let you know if I think I spent my money wisely.

Background

Harper's electronic ignition kit is brand new in the last 6 months (Fall, 2003) and is specifically designed for the V7 / V700, 750 Ambassador and 850 Eldorado loop frames. The installation promises to be quick and easy, as no modifications to the motorcycle are needed. To my knowledge, this is the only electronic ignition kit ever made for loop frames (and about 30 years tardy, too).

Alternatives

I do know of at least one person who adapted a Dyna III electronic ignition system and distributor from a Tonti frame bike to an Ambassador. This required a little creative grinding to the generator to allow sufficient room for the distributor assembly to rotate while setting the timing. He was happy with this set up and used it until the Dyna III went bad. Anticipating the eventual demise of the Dyna III, he was carrying a spare distributor with the points already set. A few minutes later, he was back on the road. I certainly plan to carry a spare set of points and condenser, for just such an occurrence - especially with an electronic ignition system that is as new as this one is.

The kit

Apr 08, 2004 - - The kit arrives and is opened with eager anticipation. Contents fall into two classes: boring and exciting.

The boring contents are those items that I already have, are in good shape, and that I don't need to replace: 1 rotor, 1 distributor cap, 2 spark plug caps, 1 spark plug wire set, and 3 ignition wire boots. My perception is that these are just filler items intended to make the kit appear larger, more comprehensive, more impressive, and worth USD $330.00. That being said, it is nice to start off with brand new stuff all around.

The exciting items include the coil and the electronic ignition igniter. Both of these components are made by a company called Pertronix. Pertronix does NOT sell directly to the public. Additionally, Harper's Moto Guzzi has an exclusive agreement with Pertronix regarding the electronic ignition igniter. So, while you may be able to find the coil from another Pertronix dealer, and you can certainly find the boring pieces from any one of a number of sources, you won't be able to get a hold of the electronic ignition igniter - which is the brains of the system and is precisely what you need.

The coil is their "Flame-Thrower" model, part number 40611 (black in color, epoxy filled, 3.0 Ohm, designed for 12 volt electrical systems, 40,000 available volts, draws a maximum of 4 amperes, but typically draws 2 amperes). If the coil goes bad outside of the 90 day warranty, a replacement can be had from a Pertronix dealer for around USD $50.00.

The electronic ignition igniter is their "Ignitor" model, part number MR-121 (RPM range: 0 - 15,000; Coil resistance: 1.5 ohms or more). The igniter is a two-piece setup. One part is a plate that replaces the standard points plate. This piece has two wires that connect to the coil. The other part is a magnetic rotor that fits over the cam on the distributor shaft. Both of these pieces are labeled with the model number (MR-121).

Warranty

Harper offers this warranty: "Harper Accessories warranties the Harper's Ignition against defects in materials and workmanship for a period of 90 days from date of purchase (must have invoice for return). Improper installation or any alteration of the product renders all warranties null and void. Warranty is limited to the replacement or repair of the product only, which is at the discretion of Harper Accessories."

However, the manufacturer of the coil (Pertronix) offers a 90 day warranty on the coil and a 30 month warranty on the electronic ignition igniter.

I am happy to see that the manufacturer is willing to stand behind the electronic ignition igniter for 30 months. I see that as the component most likely to fail, anyway. Too bad Harper Accessories isn't willing to do so. If I have trouble outside 90 days, I guess I'll try to deal directly with the manufacturer. Although since Harper's has an exclusive agreement with them, I'm doubtful that I'd get a replacement.

Installation instructions (taken directly from the installation sheet provided by Harper)

Steps:

1. Installation is very simple and straight forward. It is simply the removal and reinstallation of ignition parts that are normally changed during a tune-up.
2. Remove the fuel tank from the bike and remove the old ignition coil, distributor cap, rotor, spark plug and coil wires, and points plate.
3. Replace the old coil with the high output coil from the kit using the existing coil bracket. Note: Do not use any other coil with this igniter unit.
4. Install the igniter plate in place of the old points plate being careful to reconnect the coil power wire 12 volt positive (+) to the positive (+) side of the coil along with the red wire from the igniter. Connect the black wire to the negative (-) terminal on the coil.
5. Note: If your bike has a tachometer, the tach wire should be connected to the black (negative) (-) terminal on the coil.
6. The magnetic rotor is shaped internally to fit over the points cam. It is a slip fit over the cam and will press on easily if aligned properly.
7. Install the new distributor rotor and distributor cap with the new spark plug and coil wires.
8. Check the ignition timing with a strobe light by revving the motor until the distributor is fully advanced and adjust the timing by turning the distributor until the full advance mark on the pulley is aligned with the arrow on the engine.

Additional installation instructions

Although my assumption was that the condenser is no longer needed, the above instructions don't make any mention of it. A quick call to Harper's and my thoughts were confirmed. Plus, I got another tidbit.

It is possible for loop frames to run with the distributor reversed 180° - using the standard points and condenser. However, loop frames won't run that way with the new electronic ignition. One way to quickly check if your distributor is properly inserted is to bring the left hand cylinder (number 2 cylinder) to top dead center on the compression stroke (free-play on both valves). At this point, you should be able to look at the distributor and determine which cam lobe the points are on: the wide lobe or the narrow lobe. If you are on the narrow lobe, then you are exactly where you need to be. If you are on the wide lobe, then you need remove the distributor, rotate the shaft that runs through the distributor 180°, and reinsert the distributor. Be sure to make careful observations (and maybe even a drawing) before removing the distributor so that you know exactly where the distributor needs to be located.

Installation

Apr 10, 2004 - - Saturday morning arrives with temperatures between 25° and 30° Fahrenheit; a lovely Minnesota Spring day! Out to the garage and I commence installation following the instructions provided above. It really is an easy installation. The only aspect of the setup that was only mildly disappointing is that the leads on the coil are fastened with standard sized nuts, rather than metric. A 10 mm wrench comes close, but a 3/8" wrench is what's needed. That aside, the kit fit perfectly.

The engine started after a few cranks, but was running rough. I expected this as I knew I would need to adjust the timing. So I revved the engine, shot my timing gun at the pulley, and dialed the distributor in. This procedure requires the use of three hands unless you tighten the spring loaded adjusting screw on the underside of the twist grip throttle while the engine is revved, which is what I did. Now the engine was running great!

The test ride

Apr 10, 2004 - - On go the gloves and helmet and I rode across the street to the grade school parking lot for a short warm-up ride. Everything seemed great, even the snow flurries! So off I headed for little faster test ride on city streets (top speed around 45 - 50 MPH). The engine revved well, idled nice, and cruised like it should. I was a little cold at this point, so I headed back home. The highway test will have to wait for warmer weather.

Apr 11, 2004 - - Warmer weather has arrived! I took the Ambassador out for an 80 mile run. 40 miles were two-lane (twisties, straights, small towns; 35 - 70 MPH) and 40 miles were straight highway (70 - 80 MPH the whole way). The timing and ignition worked very well...the Ambassador just felt great. I didn't check the fuel mileage, but I will next time.

Apr 14, 2004 - - I took the Ambassador out for a 100 mile spin through the Minnesota River Valley. Some twisties, some straights, several quaint Minnesota towns, beautiful scenery - especially at sunset, a very enjoyable ride. Timing and ignition were flawless and I was very happy with the performance at highway speeds (60 - 80 MPH), as well as throughout the rest of the range. The bike just seems to respond better to the throttle with the electronic ignition. My fuel mileage was 38.2 M.P.G.

Apr 30, 2004 - - I took the Ambassador up to Duluth, MN to purchase my Aerostich suit. It's about 187 miles each way on Interstate 35. I ran the bike about 70 the whole way there and back...never missed a lick! My fuel mileage was 38.2 M.P.G.

Apr 27, 2005 - - It's been a year now and I've ridden the Ambassador quite a bit. I've never had a lick of trouble with the electronic ignition. I'm quite pleased with this upgrade.

Nov 07, 2005 - - In early October - while I had my transmission out to repair the leaking camshaft plug - I failed to properly insulate the wires going to the ignitor module upon reassembly. The wires shorted and fried the ignitor less than a mile from my house. Ug. So, I gave Pertronix a call. After diagnosing the problem, we discovered that the ignitor was indeed destroyed. Sending them my ignitor and a copy of my original receipt, Pertronix sent me a new ignitor. Great company. Great service. Great warranty coverage. Enough said.

Sep 03, 2006 - - I was heading out for a ride but got no further than the front entrance to my subdivision. Bike died suddenly. I checked the petcocks and found that I had forgotten to turn them on. I turned them on, but the bike absolutely would not start. I thought maybe I had flooded it. No matter, I pushed the bike back to my house...hot, humid, sweaty, disgusted. Pulled both plugs to check for spark. None. Tested the coil, it is fine. Performed the battery of Pertronix tests from the last time I had been through this. The Pertronix unit failed every test. Out with the Pertronix unit, in with the tried and true points and condenser system. Crank the engine over and it roared to life. This time, I'm absolutely certain that nothing was grounding out on anything else...and I'm beginning to wonder about last time, too.

My initial conclusion

I'll be the first one to admit that I dislike points and condenser systems. Not just on Moto Guzzis, but on any machine. Yes, they work; but they've always taken more of my time and given me more headaches than I care to put up with. Given what I've said here, I may be a little biased in my opinion - so take that into consideration.

I'm glad I purchased this electronic ignition kit. My Ambassador runs better now than it ever has before. As long as the electronic ignition doesn't go out on me, I think I'll remain happy.

Now, if you are happy with your current system and don't want to change to electronic ignition, then don't. I think you are well justified in choosing to stay with a tried and true technology. It sure is easier to repair or replace points and condenser systems in the middle of nowhere on your around-the-world tour.

But, if you are of like mind when it comes to points and condenser systems, and are tired of fiddling around under your distributor cap, I recommend that you purchase this kit.

My conclusion after a year and a half of use

While I was waiting on my replacement ignitor module from Pertronix, I put the standard points and condenser back in and road it that way for a while. Performance seemed identical (contrary to my initial - perhaps optimistic - impression). On future projects, I highly doubt I will purchase another electronic ignition kit. Instead, I'll use the cheap, tried-and-true points and condenser set up.

Final analysis

With two failures of the Pertronix unit, I'm definitely sticking with points and a condenser.

Pertronix documents

The following documents are applicable to installing and troubleshooting the Pertronix ignitor. USE AT YOUR OWN RISK!!!

To view PDF files, you will need to download and install the free Adobe Acrobat Reader version 5.0 or higher.

NOTE: If you have trouble viewing PDF files inside your browser, try saving them to your computer (right-click the link, then choose the save option). Then, open each file directly in Adobe Acrobat Reader.

• Back to top

Fuse block relocation

• Print this section

Some loop frame owners like to relocate the standard fuse blocks to alternative locations. Reasons for this include (1) reducing wire clutter at the headlight, (2) making the fuses more easily accessible, and (3) tinkering is just plain fun.

Stephen Brenton's side cover fuse block (in his own words)

I remade the battery tray using 316SS. Then decided to attach an after market fuse panel to an upright leg, which also serves as a battery hold down. All this hides behind the (easily accessible) left side cover.

So far I've only got 3 leads from the fuse block, purple is horn, blue is headlights, red is ignition. (I made my wiring harness so I could do exactly what I wanted.)

Stephen Brenton's fuse block and battery hold downStephen Brenton's fuse block and battery hold down

• Back to top

Generator bearing cross-references (Bosch)

• Print this section

Large Bearing (MG# 12700226) located at the front of the generator (pulley side)

• 17 mm ID x 40 mm OD x 12 mm thick
• Bearing numbers for single sided shielded bearings (as original)
  • FAF 203KD
  • FAG 6203 Z
  • FED 1203F
  • MRC 203-SF
  • ND 7503
  • New Departure 7503
  • NH 203P
  • RIV 01 APL
  • SKF 6203 Z
  • STEYR 6203 Z
• Bearing numbers for two-sided sealed bearings (completely fine to use and I consider an upgrade to the orginal)
  • FAF 203PP
  • FAG 6203.2RS
  • FED 1203RR
  • MRC 203-SZZ
  • ND Z99503
  • New Departure Z99503
  • NH 203KK
  • RIV ALN 17
  • SKF 6203-2RS
  • STEYR 6203.2RS

Small Bearing (MG# 12700217) located at the rear of the generator (non-pulley side)

• 15 mm ID x 35 mm OD x 11 mm thick
• Bearing numbers for single sided shielded bearings (as original)
  • FAF 202KD
  • FAG 6202 Z
  • FED 1202F
  • MRC 202-SF
  • ND 7502
  • New Departure 7502
  • NH 202P
  • RIV 02 APL
  • SKF 6202 Z
  • STEYR 6202 Z
• Bearing numbers for two-sided sealed bearings (completely fine to use and I consider an upgrade to the orginal)
  • FAF 202NPP
  • FAG 6202.2RS
  • FED 1202RR
  • MRC 202-SZZ
  • ND Z99502
  • New Departure Z99502
  • NH 202KK
  • RIV ALN 15
  • SKF 6202-2RS
  • STEYR 6202.2RS

• Back to top

Generator bearing cross-references (Magneti Marelli)

• Print this section

Large Bearing (MG# 95181209) located at the front of the generator (pulley side)

• 15 mm ID x 35 mm OD x 11 mm thick
• Bearing numbers for open bearings (as original - reuse original metal shields)
  • FAF 202K
  • FAG 6202
  • FED 1202
  • MRC 202-S
  • ND 3202
  • New Departure 3202
  • NH 202
  • RIV 02 A (original manufacturer and code of bearing)
  • SKF 6202
  • STEYR 6202
• Bearing numbers for two-sided sealed bearings (completely fine to use and I consider an upgrade to the orginal)
  • FAF 202NPP
  • FAG 6202.2RS
  • FED 1202RR
  • MRC 202-SZZ
  • ND Z99502
  • New Departure Z99502
  • NH 202KK
  • RIV ALN 15
  • SKF 6202-2RS
  • STEYR 6202.2RS

Small Bearing (MG# 95181219) located at the rear of the generator (non-pulley side)

• 12 mm ID x 32 mm OD x 10 mm thick
• Bearing numbers for two-sided sealed bearings (as original)
  • FAF 201NPP
  • FAG 6201.2RS
  • FED 1201RR
  • MRC 201-SZZ
  • ND Z99501
  • New Departure Z99501
  • NH 201NN
  • RIV ALN 12 (original manufacturer and code of bearing)
  • SKF 6201-2RS
  • STEYR 6201.2RS

• Back to top

Generator belt cross-references

• Print this section

Thanks to Mark Etheridge of Moto Guzzi Classics and Bob Greene for providing key starting information for these cross-references.

Magneti Marelli generator (MG# 12702500)

The original belt was a Pirelli 60404/A.

• Europe: Goodyear 10AV0775
• Dayco 15300 (metric part number 11A0760). 30.60" outside circumference, 30.00" effective length, 0.44" wide, 36°
• Dayco 15305 (metric part number 11A0775). 31.10" outside circumference, 30.50" effective length, 0.44" wide, 36°
• Dayco 15310 (metric part number 11A0785). 31.60" outside circumference, 31.00" effective length, 0.44" wide, 36°
• Gates 7300. 777 mm (30.58") outside circumference, 762 mm (30") effective length, 10 mm (0.41") wide, 36°

  Ken Wisdom had the following experience with the Gates 7300 belt:

  I tried the 7300 model belts on my Magneti Marelli generator equipped bike and I had to use about 6 shims on the inside and it was still pretty tight. I then tried a 7312 belt (same width, slightly longer) and it seems to fit very well. 2 shims inside 2 outside. I do have the genny mounted correctly with the stud in the hole on top of the engine. Thought this might help.

• Gates 7305. 792 mm (31.18") outside circumference, 777 mm (30.6") effective length, 10 mm (0.41") wide, 36°
• Gates 7312. 802 mm (31.58") outside circumference, 787 mm (31") effective length, 10 mm (0.41") wide, 36°
• Goodyear 15305. 30.000" effective length, 0.44" wide
• Goodyear 15321. 31.500" effective length, 0.44" wide

Bosch generator (MG# 12702505)

The original belt was 10 mm wide, 8 mm deep, and 754 mm long and was made by Pirelli.

Note: These belts should also work for any bike that has a Bob Nolan/Greg Field alternator conversion.

• Europe: Goodyear 10AV0750
• Europe: Gates 6210MC
• Dayco 15290 (metric part number 11A0735). 29.60" outside circumference, 29.00" effective length, 0.44" wide, 36°
• Dayco 15295 (metric part number 11A0750). 30.10" outside circumference, 29.50" effective length, 0.44" wide, 36°
• Gates 7290. 751 mm (29.58") outside circumference, 737 mm (29") effective length, 10 mm (0.41") wide, 36°
• Gates 7292. 758 mm (29.83") outside circumference, 743 mm (29.25") effective length, 10 mm (0.41") wide, 36°

  I've used the Gates 7292 belt on a Bosch equiped Ambassador and Eldorado with no problems. If I had to recommend a single belt that I am most confident will fit Bosch equiped models, the Gates 7292 would be it.

• Gates 7295. 764 mm (30.08") outside circumference, 749 mm (29.5") effective length, 10 mm (0.41") wide, 36°
• Goodyear 15295. 29.000" effective length, 0.44" wide
• Goodyear 15301. 29.500" effective length, 0.44" wide

• Back to top

Generator bracket

• Print this section

There are a number of way that every generator bracket should be improved BEFORE bad things happen (and bad things will eventually happen if improvements are not made). I've labeled each of the following with a "required" or "recommended" rating that reflects my personal belief about each modication.

Generator belt

Required. Don't over tighten the generator belt. It is far better for the belt to be too loose rather than too tight. Running the belt too tight will put a lot of pressure on the generator bracket and can crack the bracket or pull the bracket securing bolts out of the block.

Generator bracket securing bolts

Required. The two bolts that secure the generator bracket to the engine block should be changed to studs. McMaster-Carr item number 98867A310 is what I recommend (30 mm x 8 mm x 1.25 mm). Screw the long end into the block with red loctite.

Generator locating pin

Required. There is a locating pin at the front of the generator that fits into a corresponding hole in the engine block. Make certain that the locating pin is well secured into the body of the generator. The use of blue loctite is a good idea. Also, ensure that when the generator is mounted in the bracket, that the body of the generator comes into contact with the curve in the engine block. This curve serves to support the front of the bracket and there should be firm contact between the bottom of the generator and top of the engine block.

Generator bracket

Recommended. Weld an additional brace to the bracket that extends to the front-most distributor securing bolt. This one modification adds to the strength and stabiliy of the generator bracket. It also greatly reduces the stress on the two generator bracket securing bolts (which should be changed to studs).

• Back to top

Generator brush cross-references

• Print this section

I extracted this recommendation from Ralf Brinkmann off of the Yahoo! Loopframe_Guzzi news group.

Bosch Generator

• Volkswagen part number 111 903 515 E (for 6 volt generators)
  The dimensions of each brush are 6 mm thick x 22 mm wide x 25 mm long
  Fits: Beetle 1946-1966; Ghia 1956-1966; Type 3 1962-1966; Bus 1952-1966

Magneti Marelli Generator

Unknown.

• Back to top

Labels for fuse panel and distribution block

• Print this section

A big thanks to Charles Hamer for digitizing the labels for the fuse block and distribution panel. There are 2 pages in this PDF file. The first page shows the original labels. The second page shows a cleaned up version of the labels.

Note on printing this PDF file: When printing this PDF file, be absolutely sure that "Page scaling" is set to "None". If you don't do this, your print will not be of the proper size.

To view PDF files, you will need to download and install the free Adobe Acrobat Reader version 5.0 or higher.

NOTE: If you have trouble viewing PDF files inside your browser, try saving them to your computer (right-click the link, then choose the save option). Then, open each file directly in Adobe Acrobat Reader.

• Back to top

Rubber boot for the oil pressure sending unit

• Print this section

Thanks to Charles Hamer for sending me this information in a private communication:

For the little rubber boot to cover the oil pressure sending unit (MG# 12717600), Napa has one that fits like a glove.

Napa part number 727302.

Napa part number 727302; rubber boot for oil pressure sending unit

• Back to top

Rubber boot for the starter button

• Print this section

Thanks to Charles Hamer for sending me this information in a private communication:

For the little rubber boot to cover the 2 terminals for the starter button (MG# 25707100), Napa has an awesome one used for distributors, and it fits our starter buttons terminals like a glove.

Napa part number 727300.

Napa part number 727300; rubber boot for starter button

• Back to top

Solenoid cross-reference (for Bosch starters)

• Print this section

The original Bosch part number is 0-331-302-022 or 0 331 302 022 or 0331302022. Here are several generic cross-references for this solenoid. I haven't tried all of these myself, but I understand they work just fine.

• Advance Auto Parts: Standard SS221
• Advance Auto Parts: Borg Warner S523
• Advance Auto Parts: Niehoff SD29961
• Advance Auto Parts: GP Sorenson 285011
• Napa Auto Parts: Echlin ST222

The solenoid is used on the following vehicles (with manual transmissions...I believe the automatic transmission uses a different part):

• 1968 - 1973 Volkswagen Fastback
• 1968 - 1973 Volkswagen Squareback
• 1969 - 1974 Volkswagen Karmann Ghia
• 1969 - 1979 Volkswagen Beetle
• 1971 - 1972 Volkswagen 411
• 1973 - 1974 Volkswagen 412
• 1974 - 1979 Volkswagen Transporter
• 1975 - 1979 Volkswagen Campmobile
• 1981 Volkswagen Vanagon
• 1970 - 1976 Porsche 914

• Back to top

Solenoid mounting

• Print this section

Thanks to Paul Linn for providing this information on the Yahoo! Loopframe_Guzzi news group. In Paul's own words:

If you put the solenoid on upside down then the wrong terminal will get hooked to the positive and it will get very hot when you turn the key on. Ask me how I found this out! The part number etc on the solenoid should be visible when looking at it from above and the starter relay terminal will be on the outside when it's mounted on the bike.

• Back to top

Starter, Solenoid, and Starter Relay

• Print this section

Troubleshooting

Sometimes pushing the start button results in clicks, and the starter does not turn the engine. There are a number of things you can try when this occurs:

1. First off, give the solenoid a good rap with a rubber mallet. It may be that things are just a little bound up and the rap may be all that's needed. Growing up, we had a lawn mower that required this treatment...it worked for years!
2. Check all of your connections to be sure that they are making good contact.
3. Since a clicking sound is heard, the starter button is most likely fine. The starter wouldn't be making any sounds if the button weren't making the connection.
4. It may be that the battery is discharged and not supplying sufficient power. If you have a charger, you can charge it and see if that makes a difference. Alternatively, you could use jumper cables from a running automobile to provide sufficient juice.
5. If the starter still clicks when you know you have sufficient battery power, then it's time to determine whether or not the starter is bad by bypassing the starter relay and the solenoid with a pliers or a screwdriver or something to make the connection...Here's how:
   1. Remove the small wire from the solenoid (the one that attaches with a spade connector). Leave the big wire connected.
   2. Use a pliers/screwdriver/etc to connect the big bolt to the small spade connector.
   3. Make sure the key is on, and the starter should rotate when contact is made...there will be some sparks when you make the connection, but that is normal for this procedure.
6. Now, if the starter rotates and you know that you have a good battery and starter button, then only one of two things can be the culprit: either the solenoid is bad or the starter relay is bad.
7. Start with the relay. My original relay went bad and was replaced with a generic relay. It looks different from the original and won't mount the same, but works great.
8. If that doesn't fix the problem (at least you now have a cheap spare), it is time to address the solenoid (which is a more expensive replacement part). I don't see any harm in taking the solenoid apart and cleaning things up, that may correct the problem.
9. If cleaning things up doesn't fix the problem, get a new solenoid.

How to bench test the starter and solenoid

I extracted this information from Bruce Giller off of the old Topica Loopframe_Guzzi news group (which has now moved to Yahoo!).

You can bench test the starter off the bike. Clamp it in a vise for there is no point in trying to hold it with your hands; lots of torque. Get a well-charged battery and some jumper cables. Clip the negative to the body of the starter.

Test the solenoid: apply the positive cable to small wire connection (usually a spade type) on the solenoid; you are playing the part of the starter switch. The solenoid should click loudly and throw the ring teeth engagement gear out into the nose of the starter. The starter should not turn.

Test the starter: now apply the positive cable to the big nut on the solenoid that was NOT used for the battery cable on the bike. Here you are bypassing the solenoids' internal T-bar electrical connector and feeding current directly to the starter. The starter should whirrrrr confidently but the ring teeth engagement gear should not budge.

If both components work independently, you can bench test the starter as a whole. Clip the positive cable to where the bikes' battery cable used to attach (big nut). Get a small jumper wire and attach one end to the positive cable and the other to the solenoid connection. Now the solenoid should kick out the engagement gear AND the starter should turn.

How the starter works and more troubleshooting

I extracted this information from Patrick Hayes off of the old Topica Loopframe_Guzzi news group (which has now moved to Yahoo!).

Look at how the system operates. It must be a clear, two-step process. When you hit the button, the relay and then the solenoid get energized. The solenoid pulls its core inward, which pushes the starter gear forward through a pivot lever. The starter motor is not yet energized and does not yet spin.

As the pinion gear moves forward, the forward edge of its teeth are supposed to impact against the rear edge of the ring gear teeth. Both sets of teeth should be angled or tapered in some way to discourage a direct, face-to-face tooth hit. At the point of impact, the pinion should be forced to rock one way or the other to slide between mating ring gear teeth.

As the teeth fully mesh and engage, the huge contacts down at the back end of the solenoid inside its cap come into play. When these contacts hit, the starter windings themselves become energized and the motor starts to spin.

So, you have one of two problems if the starter does not always cleanly engage the ring gear.

First, is there some reason that the gear teeth do not embed? Has this error caused the teeth to grind against each other, square off, and exacerbate face-to-face locking? Can you get at the damaged teeth with a dremel grinder and restore a pointed face condition?

Second, is the starter being energized to spin before the gears are meshed? And here again we have two potential problems. Somehow the starter is getting juice before the gears are meshed.

First, has there been enough wear to the pivot and the various mechanical points of the lever system so that it is not pushing the pinion gear as far forward as it used to? Not sure how to repair that, but you could remove the lever and have a little weld dab added to it to restore original thrust dimension.

Second, has someone repaired, cleaned or replaced this solenoid? Was an alternate substitute solenoid used? If it is the original solenoid, and it was cleaned or repaired, was the original cap gasket saved or reproduced? The physical position of the solenoid rear cap (and thus its internal contacts) are critical to the design of this system. If you move the cap slightly forward (by omitting the cap gasket) you allow the starter contacts to come into play before the plunger thrust is complete. If you use an alternate solenoid, the dimensions for thrust and contact may not be completely accurate.

I would suggest a thorough tooth inspection and some lubrication of the pinion shaft to get the gear sliding easier. You can run the solenoid repeatedly on the floor with some test wire and observe its action. Just be sure to disconnect the heavy starter lead so you don't energize that spin or the motor will jump all over the place.

I would suggest a removal and very thorough inspection of the pivot system and the fork face of the pivot against the pinion gear. Is there some substantial wear and can it be improved or corrected?

I would suggest disassembly of the solenoid and the addition of a double or triple thick gasket between the end cap and the solenoid body. By adding gasket thickness here, you are moving the motor contacts aft and delaying the instant point of energizing the starter. The plunger has to go deeper before it makes the motor spin. Perhaps by stacking gaskets, you can delay it long enough to get deeper tooth penetration before spin. At any rate, what you have now is a rotary grinder and you are damaging the face of the pinion and ring teeth. By doing so, you are making the gear contact position worse as it respects the internal solenoid contact position. You have to get tooth penetration BEFORE spin. Doing the gasket stack might be enough to counteract the tooth wear already in place.

One last thought. You might ignore ALL of the above and just inspect the wiring at the starter and solenoid. You maybe haven't done something to short this wiring in some way, or hooked it up incorrectly so that the thrust action and the spin action are happening simultaneously? That would be a case for failure for sure. You have to separate these two functions in time and space. The starter relay ONLY energizes the solenoid. It is the action of the solenoid which energizes the starter windings. I'm trying to imagine how you could hook up contacts incorrectly to get the motor spinning by the relay circuit rather than by the solenoid circuit. Could happen I suppose.

Also, the floating contact on the back end of the solenoid plunger should be a spring loaded bar. Might be possible to lift that bar against its spring and insert something like an o-ring or split washer onto the stem which would effectively move this floating contact forward and thus require a deeper solenoid core penetration before starter contact. This would then require deeper penetration of the pinion/ring pair before spin. There is no spin action here and not all that much heat, so an o-ring might give you the adjustment you seek.

• Back to top

Starter and solenoid repair (Bosch)

• Print this section

I've been meaning to rebuild a couple starters and solenoids I've had for quite some time now. One functioned perfectly but needed cosmetic improvement. That is the starter you'll see pictured below. The solenoid on the other starter functioned fine, but the starter did not turn. Cleaning up the commutator solved that problem.

1. Always start with a spotless work area!
   
   

   

2. OK, that's much better :> Here is the crusty specimen. Time to get started.
   
   

   

3. First, remove the wire connecting the starter to the solenoid.
   
   

   

4. When you are reassembling, you can reference the terminals so you make sure you align the proper terminal on the solenoid.
   
   

   

5. Now remove the screws the secure the solenoid to the starter.
   
   

   

6. This is what they look like. The wetness is from PB Blaster...expect to soak these and use an impact driver (the kind with a hammer) to get them unstuck. Upon reassembly, be sure to use loctite on these screws. If you don't, you run the real risk of them loosening up and falling out.
   
   

   

7. Remove the solenoid from the starter. Note how the hole in the solenoid's arm fits around the lever.
   
   

   

8. Here is a close up picture of the solenoid arm and plunger. I screwed the screws back in a few threads so I wouldn't lose them.
   
   

   

9. This nut secures the bolt that acts as a pivot for the arm that engages and disengages the bendix with the ring gear. You should be able to move the arm back and forth and watch the bendix (starter gear) slide back and forth.
   
   

   

10. Remove the nut and bolt. You won't be able to withdraw the arm just yet.
    
    

    

11. Next, remove the screws that secure the small rear cover.
    
    

    

12. Pull it off and this is what you'll see.
    
    

    

13. Withdraw the "U" shaped retainer from its slot.
    
    

    

14. Withdraw the shimming washer.
    
    

    

15. I first thought this was just one washer. But while I was cleaning everything up, I found it was actually a stack of 3 washers stuck together: 1 thick and 2 thin.
    
    

    

16. Remove the rubber seal.
    
    

    

17. Now remove the big screws. PB Blaster is your friend.
    
    

    

18. With the big screws removed, you can pry off the big end cap. Just a twist with a small screw driver is all mine needed.
    
    

    

19. Wiggle it off. It only fits one way.
    
    

    

20. Here is what is inside.
    
    

    

21. Here are all the parts for the top in the order in which to reassemble them.
    
    

    

22. There are 4 brushes total. 2 are secured to the brush plate and need not be removed. The remaining 2 are soldered to the field coils and must be removed. Just pry the spring back and pull the brush out.
    
    

    

23. Here the brush is removed.
    
    

    

24. Now the brush holder just slides off...you can get a better view of 2 brushes that are attached to the field coils.
    
    

    

25. Here is a view of the brush holder from the underside. It doesn't matter how it goes back on as the connections are identical.
    
    

    

26. Now you can pull the main body off.
    
    

    

27. Here it is removed. It only goes back on one way...I didn't get a picture of it, but there is a relief for the little rubber piece that fits between the starter and solenoid.
    
    

    

28. Now you can withdraw the winding. It comes right out and may bring the engagement arm along with it.
    
    

    

29. Here is how the engagement arm is supposed to engage the bendix. It is reversible so don't worry about right side up or anything like that.
    
    

    

30. Here is that little rubber piece that fits between the starter and solenoid holes. Pluck it right out.
    
    

    

31. To remove the bendix, use a 13 mm 1/4" drive deep-well socket to drive the steel collar down off of the wire ring. Tap the socket with a hammer.
    
    

    

32. Now pry off the wire ring.
    
    

    

33. And here is the bendix. I pulled it off as an exercise to see if I could do it, but I wouldn't bother with it unless it was suspect. It is very difficult to get the steel collar back around the ring. I spent more time doing that than anything else. It finally work after a spent a lot of time bending the wire ring with a pliers to get it very close to the size of the recess. Doable but not fun.
    
    

    

34. And here are the 3 pieces.
    
    

    

35. The winding. No need to drive the shaft out...I'm not that curious! That is it for the starter...from here you can clean up the commutator (the part that the brushes run on) with some fine sandpaper. You can also replace the brushes with new ones. Just a bit of soldering will take care of that. I gave everything a bath in some degreaser and then used my wire wheel to clean up the nasty exterior bits.
    
    

    

36. Alright, onto the solenoid. Remove the 2 screws that secure the cap. They may be covered in some silicon glue that you'll have to dig out first.
    
    

    

37. Here are the screws.
    
    

    

38. Now heat up the connections with a soldering iron. Once the solder has liquefied, pull upward on the cap with your hand. Then do the other side. Move back and forth until the cap comes free.
    
    

    

39. Here is the cap as it was removed.
    
    

    

40. A look at the contacts inside the cap. Clean these up well. I like to use a tiny wire wheel on my Dremel tool. Then remove any residue with a cleaner (like rubbing alcohol or carb cleaner or such).
    
    

    

41. Here is how the cap goes back on. In the picture I'm holding it backwards...so don't get confused. The side that has two wires angling up to the other (LEFT side in the photo) goes to the terminal on the cap with the spade connector. You can see these two wires better in the photos above. Don't get this wrong or you'll have to swap it back around.
    
    

    

42. Carefully remove the first cardboard shim.
    
    

    

43. Carefully remove the second cardboard shim. Yes, I found two of these on mine. Combined thickness was 1.5 mm or 0.6 in. Be very careful with these and do not lose or destroy them. The thickness they provide is critical. If they are totally destroyed, replace them with shims of identical thickness.
    
    

    

44. As usual, assembly is the reverse of disassembly. Be sure to use anti-seize on all of the threads EXCEPT for the bolts that secure the solenoid to the starter body...use blue LOCTITE on those. Put some grease on the bushings and on the shaft where the bendix slides.
    
    Here is the finished starter and solenoid reassembled and painted. I painted the starter with black truck bed liner in a spray can (thanks to Mark Etheridge of Moto Guzzi Classics for that tip) and I primed and painted the solenoid body with gloss black paint. Stainless steel washers and nuts at the rear of the solenoid complete the project. All in all, I was able to rebuild two starters/solenoids in about four hours of time one humid Florida Saturday afternoon in August, 2006.
    
    

    

• Back to top

Voltage regulator cross-references

• Print this section

I extracted some of this information from the old Topica Loopframe_Guzzi news group (which has now moved to Yahoo!).

Bosch Generator

The voltage regulator listed below was used in many Dodge vehicles in the 60's and Volkswagen Beetles from 1959 to 1979, so if you can't remember the part number, perhaps you can remember a 1969 Dodge Monaco or a 1971 Volkswagen Beetle.

• Advance Auto Parts (GP Sorensen): 265002.

  I had this unit installed on my Ambassador with a Bosch generator and it worked great. It bolts on without any modifications and wiring it up is simple (see images below for specific wiring connections).

  

  

  

Magneti Marelli Generator

The voltage regulator listed below was used in the 1963 Ford Falcon (and probably a lot of other vehicles).

• Advance Auto Parts (GP Sorensen): VR203.

  This is the unit that Keith Ruff installed on his loop during the 2005 National rally in New Cumberland, WV. It works great.

• Back to top

Wiring diagram - headlight relay

• Print this section

The following schematic shows how to utilize relays for the headlight high and low beam circuits. This simple modification does wonders for extending the life of your switches.

To view PDF files, you will need to download and install the free Adobe Acrobat Reader version 5.0 or higher.

NOTE: If you have trouble viewing PDF files inside your browser, try saving them to your computer (right-click the link, then choose the save option). Then, open each file directly in Adobe Acrobat Reader.

• Back to top

Wiring diagram - relays

• Print this section

Relays are very beneficial anytime you don't want to run a large amount of current through a switch that isn't designed to handle it. Here's how to wire a relay.

Every relay has terminals that are marked. Usually, there are either 4 or 5 terminals, with the following markings:

• The terminal numbered 86: This is the "switch" terminal. Normally this is the wire that would go directly from the switch to whatever device you are operating. Now that a relay is involved, the wire from the switch would run directly to this terminal.
• The terminal numbered 85: This is the "ground" terminal. This is a new wire. It works in conjunction with the terminal numbered 86 and completes the "switching" circuit.
• The terminal numbered 30: This is the "power-in" terminal. This is a new wire. It supplies power from the fuse block (usually).
• The terminal numbered 87: This is the "relayed" or "normally open" terminal. This is a new wire. It connects directly to whatever device you are operating.
• The terminal numbered 87 (may or may not be present): This is a duplicate "relayed" or "normally open" terminal. If you wanted to relay two items with one switch, this additional terminal could be useful.
• The terminal numbered 87a (may or may not be present): This is the "non-relayed" or "normally closed" terminal. If you wanted to turn something off whenever the relay was activated, then this terminal could be useful.

I think it is most useful to think of the relay as a light-duty "switch" that operates a heavy-duty "switch". Here's how it works. When you activate a hand-operated switch (headlight switch, driving light switch, starter button, etc.), you are completing the circuit between terminals 85 and 86 in the relay. This is the light-duty "switch" and only requires only a very small amount of amperage to be activated. Therefore, it is very gentle on the hand-operated switch and causes very little arcing across the contacts. Now, once the circuit is complete between terminals 85 and 86, the relay operates a heavy-duty "switch" between terminals 30 and 87. This heavy-duty "switch" is able to handle a lot of amperage without the destroying the contacts (typically 20, 30, or more amps for the automotive industry). Using a relay, you are able to operate a device that draws a lot of current with a hand-operated switch designed only for low current devices.

Many modern motorcycles come equipped with relays for numerous devices, such as starters and lights. However, if you are adding additional driving lights to a modern bike, or upgrading the lights on an older bike with higher wattage bulbs, you'll want to install relays to protect your expensive hand-operated switch gear.

Dan Prunuske sells 25 amp micro relays and has a lot of good information on his website.

Here is a list of various part numbers that may help you track down a generic relay:

• Borg Warner R3062
• Borg Warner R681
• Bosch 0332019150
• GP-Sorensen MR38
• Echlin ECHAR230
• Echlin ECHAR201
• Mileage Plus MPEAR201SB
• Wells 19861

• Back to top

Wiring diagrams (very large and easy to read)

• Print this section

To me, there are few things more frustrating than struggling to read a wallet-sized wiring diagram. These enlarged wiring diagrams print across 20 pages each. Once you tape the pages together, you'll have a very large wiring diagram that is easy to read. I attach them to the back side of a door in my garage.

Carl Allison has created many wonderful, high quality wiring diagrams for Guzzis. His wiring diagrams are hosted here as well as on the GuzziTech website.

To view PDF files, you will need to download and install the free Adobe Acrobat Reader version 5.0 or higher.

NOTE: If you have trouble viewing PDF files inside your browser, try saving them to your computer (right-click the link, then choose the save option). Then, open each file directly in Adobe Acrobat Reader.

• Back to top

Wiring diagram - starter relay

• Print this section

The following schematic shows how to wire a relay for the starter circuit.

To view PDF files, you will need to download and install the free Adobe Acrobat Reader version 5.0 or higher.

NOTE: If you have trouble viewing PDF files inside your browser, try saving them to your computer (right-click the link, then choose the save option). Then, open each file directly in Adobe Acrobat Reader.

• Back to top

Wiring diagram - turn signals

• Print this section

The following schematic shows how to wire turn signals. This will be most useful to owners of V7 / V700 and Ambassador models, which did not come originally equipped with turn signals. It is also useful for anyone installing a new wiring harness - as even the pre-made looms do not come with the turn signal wires.

To view PDF files, you will need to download and install the free Adobe Acrobat Reader version 5.0 or higher.

NOTE: If you have trouble viewing PDF files inside your browser, try saving them to your computer (right-click the link, then cho