Disconnect cable and tie rod.
Move one lever so that shoe just barely comes into contact with drum surface. (Check this by spinning wheel and listening for the tell tale scrape of the shoes on the drum surface)
Mark this position with an upright mark on splined part only.
Repeat step 3 for other lever.
Place levers on splined parts so that the tops of the levers are now lined up with the marks made in step 3.
Rotate front lever to its upright position and connect tie rod.
Rotate rear lever to its upright position and check length of tie rod. If it,s to short or to long, adjust tie rod now so it can connect to the rear lever.
You will have to fine tune the tie rod so that both shoes contact the drum at the same time.
Connect cable, adjust freeplay and test brake action.

This same procedure can be used for the rear drum also. Your drum brakes will now be just a good as a disc setup. After following this simple adjustment procedure you will no longer have that mushy feeling most people find with the front brake switch style cable and you will be able to STOP on a dime.

Synchronizing four leading shoe brakes

by Greg Field

Center the hub by spinning the wheel and locking the brake and retightening the axle bolts.
Get all linkages to "optimum" position. This means that when the shoes contact the drum, the actuating arm and pull rod are as near a right angle as possible, for best mechanical transfer of force. Rotate the actuating arms on the shaft until this is so.
Pull off the right cable
Remove the pin for the back shoe on the left side.
Adjust slack out of the left brake cable until there is significant brake drag (light scraping is not enough).
Manually actuate the rear shoe until the brake drag doubles. Then, adjust the link rod until the pin can be re-inserted. Fine-tune adjustment if necessary to keep drag equal between the two shoes. Hopefully, the andgle between rod and arm wil still be near90 degrees.
Slacken left cable till all brake drag goes away.
Repeat steps 3 through 6 for right side.
Then adjust slack out of left cable till brake drag from the left side doubles what was already there from the right.
Adjust out slack at the hand lever, which preserves left-right synchronization.
Then, for gnat's-ass perfection, re-center the hub, and fine-tune the left-right adjustment.

When done thusly, most folks I've done this for want them de-adjusted so they're not so grabby and sudden, but this is the place to start because if your shoes aren't 100 percent perfect, this will make them the best they can be.

Here are the Steps to a Great Front Brake

by Bruce Giller

get new shoes with modern material. If your shoes are original, recycle them at a brake recliner or put them on the wall as Guzzi Art. Mark E. sells them
arc the shoes to the drum. (see instructions below)
adjust the front brakes so that both leading shoes contact the drum at the same time (see instructions below)
as the shoes wear, re-position the front drum's brake levers to compensate. Adjusting the brake cable is useful over a short range - plus the cable itself tends to lengthen. (I'm still writing this one up...it is Paul Linn's tip)

For those who want to do arc the brake shoes to the drum:

Obtain some 80 grit sandpaper with a sticky back (you can find strips of sandpaper at your local auto paint store)
Line the inside of the brake drum with one layer of the sandpaper (you will have to cut the paper to the width of the drum)
Pencil on hatch marks over the entire width and length of each shoe
Assemble wheel back on the bike.
To center the wheel, use the front brake lever several times while spinning the front tire, then hold the brake lever down while tightening the front wheel nut
Spin wheel and apply brakes a few times to sand down shoes
Remove wheel and inspect pencil marks. If some of the marks are still there, repeat Steps 3-6 until the pencil marks have completely disappeared
Remove paper from the drum and clean out the drum. This procedure will leave a pile of shoe particles inside the drum, especially if the shoes are new

You want to make sure that the two leading shoes are contacting the drum at the same time when braking. The procedure works better if you have 3 arms but can be done by one person.

make sure that your front wheel is centered on the axle. To center the wheel, use the front brake lever several times while spinning the front tire, then hold the brake lever down while tightening the front axle nut
Disconnect the metal rod connecting the two splined levers for each shoe from the front lever. It has "forked" end pieces which are held in place by a small pin with a cotter pin. The rod is welded to one end and screwed into the other.
Squeeze the brake lever to where the point where the front shoe is contacting the drum
At the same time, manually make the rear shoe contacts the drum by pulling back on the rear brake shoe splined lever
Adjust the length of the connecting rod for a tight fit between the two shoes. You probably won't get a perfect fit due to the large adjustment distance. You have to turn the forked end 180 for each adjustment. I made mine a bit tight to compensate for future shoe wear
Test the action of the front shoes. Put the cotter pin back in the front lever's pin. Now when you pull on the front brake lever, the two shoes will contact at the same time.

Brake cable replacement information

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What is so great about the Barnett front brake cables? In my opinion, several characteristics make them the best choice available today.

The cable is thick.
The individual strands are thin and numerous.
The individual strands are wound in a more longitudinal direction along the length of the cable...rather than more cross-wise.
The cable liner allows the cable to move smoothly.
The barrell ends of the cable are separate from the cable ends...allowing the cable to rotate within the barrell end. This reduces the stress on the cable and extends the life of the cable.
There is no brake switch! In my opinion, this is critical to getting adequate braking performance. No matter how good a person sets up a front brake, the presence of a brake switch inline with the cable will always deteriorate braking performance at least a little bit. In my experience, the presence of a brake switch is a major contributor to poor braking performance.
All this adds up to less stretch and more pull being transmitted to the front brake. In my experience, it makes a big, meaningful improvement.

Charlie Mullendore of Antietam Classic Cycle worked closely with Barnett to get a replacement brake cable made for his two-leading shoe front brake with civilian bars.

Here is the information from Barnett and Charlie:

Barnett wrote:

Charlie,

Most of the time we keep prints of the cables on file for future reference or it goes into a temporary file. If we have the information on the bike model so we know what the cable fits, we usually save it. We should still have the prints for your cables and I will make sure that we save it. It's never a bad idea to send the cable(s) just to make sure that the new ones are correct. If you can, let me know what the year and model of Moto Guzzi it was and I will have Joe attach it to the print for future reference. If you or any of your friends ever have a question about a cable, call us at 805-642-9435 and ask for Joe. If Joe isn't available, ask for Mark. They both work directly with the cable dept.

Chris Taylor
Barnett Tool & Eng.

Charlie writes:

I've sent all the information from the invoice and what models the same cable will fit. They've been a real pleasure to work with, prompt responses to my emails, great product, finished when they said it would be. I'll measure my old cable soon and post the dimensions if still needed also. Cheers

Charlie

Brake light switch alternative (front)

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I extracted this information from Charlie Mullendore of Antietam Classic Cycle off of the Yahoo! Loopframe_Guzzi news group. In Charlie's own words:

Having short-circuited one of my last Barnett switched front brake cables by over lubing (Doh!) and sending the other out as a warranty replacement, I was left with no way of activating the brake light with the hand lever on my '71. Last year at one of the WV Guzzi breakfasts, I remembered looking at Rob Prins' Ambo and noticed the Honda (rear) brake switch he had mounted to the fender brace that was actuated by the linkage. Decided I'd try to rig something similar up for myself, if I could find the right switch. I was digging around in a bin marked "Switches" at the shop the other night and found this new-old-stock Bosch unit that looked like it would work. Made a little "C" shaped bracket out of some scrap stainless steel and found some self-tapping stainless screws too.

The switch included a spring and clamp for around a brake rod - both were perfect for my application. Once mounted and the spring slightly tensioned, it functions perfectly. I ran the wires through shrink tubing and zip-tied it to the cable.

Looks a bit "Rube Goldberg", but does the job.

My friend Joseph tells me the switch is from a '60s Sears Allstate (Puch) 250, but I'm not sure how available they are. Did find one place in the UK that lists them: #351 and Domi Racer has two that are similar.

Brake light switch replacement (rear)

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I extracted this information from Charlie Mullendore of Antietam Classic Cycle off of the Yahoo! Loopframe_Guzzi news group. In Charlie's own words:

The '73 Eldo ("Al's Eldo") that I recently worked on had a rear brake light switch that I couldn't identify. Now I see what it was from: Stoplamp switch for all Norton Commandos, Triumph and BSA triples and Triumph 750 twins. Exact replica of Lucas No. 34815. 05-01059. It mounted up using the stock holes and had spade terminals instead of those aggravating little screw terminals of the o.e. part. At USD $7.50 it's cheaper as well.

Brake line replacement information

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Tom Christian replaced his stock hydraulic brake lines with stainless steel, black coated Goodridge lines. By doing so, he improved the braking feel and performance while maintaining the stock appearance. Here is the information from Tom:

A couple of weeks ago I installed stainless steel black coated Goodridge brake lines on my disk Eldo and rebuilt my stock 15 mm master cylinder. The improvement is significant, and the appearance remains period correct. The install was trivial, takes at most 1/2 hour, with bleeding.

Here is the part ordering info:

11315E Goodridge black stainless braided brake hose, 15"
11318E Goodridge black stainless braided brake hose, 18"
B59303C Goodridge stainless 20 degree banjo
B59403C Goodridge stainless 45 Degree Banjo (3)

I'd take at least an inch off of each hose, and go with all 4 banjos at 45 degrees if I had to do it again. The screw-on connectors need to be tight!

Gordon threw in the brass crush washers but I forgot to order new stainless steel banjo bolts - Goodridge's are nice, I've used the stainless steel on our Harley too. The old banjo bolts will work fine, however.

The whole thing was about USD $100.00. Takes less than 1/2 hour to install and bleed. Some of the parts come from different locations, so shipping was slower than usual (I usually order Monday and it arrives Thursday like clockwork for the weekend) - this added a couple of days.

When I said "new master cylinder", I meant I used MG Cycle's rebuild kit and rebuilt my stock 15 mm master cylinder - it was a mess.

Brakes - External brake return spring

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Thanks to Frank Granli who sent this information to me in a private communication. In Franks's own words:

I have installed some exposed return springs on my 4LS front brake, after an idea I saw on your excellent loopframe web page. Somebody had done this with their 2 LS rear brake. Is this something that might be of interest for other loopers? I have done so, because my 4LS brake had a tendency to almost get stucked in "on" position, the return movement was very slow. This happened even with freshly cleaned and lubricated brake arms. So, before disaster, I have installed these exposed springs, and they do help.

Brakes - Turning brake drums - 4 leading shoe brakes

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NOTE: In general, I do not recommend turning the brake drums on these machines. But, occassionally, it may need to be done. I would certainly never perform this as part of any "routine" maintenance.

Thanks to Locky who posted this information on the Yahoo! Loopframe_Guzzi news group. In (mostly) Locky's own words:

...in regards to your question about the specs for the brakes, what I think the brake shop is after is the internal diameter of the drum. I'm not sure about a 2 leader brake but the 4 leader is 219.900 mm - 220.000 mm or 8.657 - 8.661 inches. The brake shoes need to be turned while fitted to the backing plate to 219.880 mm - 219.950 mm or 8.653 - 8.659 inches. But they need to be turned while the cam is in the open position and the cam operating lever at 119.800 mm - 120.000 mm or 4.716 - 4.724 inches from the anchoring lug. That will make sure your break shoes are the same radius as the internal hub when the breaks are applied. The measurement to lock the leaver to is taken from the back of the lever where the cable attaches to the back of the cable anchoring lug. You will have to make something to lock it in this position then have it machined, and that how its done. Hope this helps, Locky.

Brake switch alternative - Front brakes

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I extracted this information from Bill Dudley on the Yahoo! Loopframe_Guzzi news group. In Bill's own words:

I recently got pissed off at the cable switch, and decide to do what I've also done to other bikes (a Honda CB400F, for example, when it's hydraulic front brake switch packed up).

I rigged up a way to mount a microswitch such that it is activated by the front brake lever. Just the slightest movement of the front brake lever will move the microswitch lever enough to light the brake, so it's now easy to flash the rear brake light at tailgaters (not that it does all that much good).

Since my Ambassador doesn't have the stock choke lever, I have the "similar, but different" one sold by MG Cycle, part LAM8405. This choke lever required that I make a spacer to raise it up about 1/4 inch, and also to rotate it's anti-rotation tit about 15 degrees. So I made a sheet metal "L" bracket that fits between the choke lever and my 1/4" spacer, and the microswitch is bolted to that. Then I needed a little "flag" that would actuate the microswitch and also fit between the brake lever and the perch.

I'm not supplying drawings with measurements since you probably won't have the same microswitch I have, or make your spacer the same way, etc., but at least this gives you the general idea.

The brake switch installed.The brake switch installed.

The installed switch showing the spacer under the choke lever.The installed switch showing the spacer under the choke lever.

The underside of the bracket, showing microswitch mounting and the flag.The underside of the bracket, showing microswitch mounting and the flag.

A slightly blurry shot of the microswitch and it's 'flag', again, with the choke lever spacer on the right.A slightly blurry shot of the microswitch and it's 'flag', again, with the choke lever spacer on the right.

Disc brake information

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Putting disc brakes on your non-disc brake loop

This information originated from posts made by Greg Field on the old Topica Loopframe_Guzzi news group (which has now moved to Yahoo!).

Putting a T3 front end on a loop frame

There are three approaches to putting a T3 front on your Eldo, but none is easy. Here are the options:

Adapt the T3 triple trees to the Eldo. This is easiest, but you then lose the heavy look of the Eldo front end (no fork shrouds). You'll almost certainly have to use the T3 fender. The T3 axle will work.
Adapt the T3 forks to your Eldo triple trees. This allows you to keep the fork shrouds and Eldo fender. There are at least two ways to do this:
1. Have tapered "adapter caps" made that bolt to the top of the T3 forks. These match the taper on the inside of the top triple tree. Bob Nolan has made these. I can ask if he'll make more. This limits you to the non-FAC dampers. See below for caliper and fender considerations.
2. Get new disc-Eldo tubes made by Forking by Frank to use with the T3 sliders. Have him make the tubes with the i.d. threads at the top like the i.d. threads on the drum-Eldo tubes (different location for the O-ring, from what I remember). This leaves you to find a way to adapt damper rods to the top of your forks. You're unlikely to find the stock set-up for a disc Eldo, so here's how I'd do it: Center-drill your drum top caps for an 8-mm stud to affix the T3 damper rods to your top caps. This is a basic set-up that I have never actually done. Better would be to get FAC dampers and have the hex cap at the top turned down (or filed down) to fit inside the tubes. Then, remove the air stem from the top of the FACs, and screw it onto the stud you have added to your top caps. I have done this. See below for caliper and fender considerations.
Have custom top triple tree made to clamp non-tapered tubes of the T3. This would likely be very expensive but may be easier in the end than option 2. See below for caliper and fender considerations.

Caliper and Fender Considerations

If you do not have a disc front fender, you can use the drum-type, if you do the following:

Swap fork sliders, left to right, which puts the calipers behind the sliders. This leaves room so that you can use the stock fender braces (or at least I was able to on the one I did).
Then, cut off the strap on each side of the fender that used to mount to the fork sliders. Best would be to weld them back on in a position that can then mount to the T3 sliders. Likely, though, no problems would ensue from leaving them off.
Insert the axle from the right (nut on the left).

Other Considerations

I cannot remember what I used for axle and spacers. I think I had some metal turned off of the shoulder of the drum-brake axle.
You'll have some daylight between the end of the fork shroud and the top of the slider, especially if you fit the longer G5-length springs and dampers. No harm in this; it just looks a bit odd.
There's probably other stuff, but I just can't remember it right now.

Disc brake parts

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Disc brake top nut and tube sleeve

Thanks to Paul Linn for providing me with these photos and measurements. The top cap nut is part number MG# 13504541. The tube sleeve is part number MG# 13504441.

Disc brake disc side hub flange / bearing carrier / disc carrier

Thanks to Paul Linn for providing me with these photos and measurements. The disc side hub flange is part number MG# 13613641.

Flange is 39.5 mm thick

Disc brake non-disc side hub flange / bearing carrier / disc carrier

Thanks to Paul Linn for providing me with these photos and measurements. The non-disc side hub flange is part number MG# 14620301.

Outer flange is 22 mm thick; 39.5 mm thick overall

Disc brake axle

Thanks to Paul Linn for providing me with these photos and measurements. The axle is part number MG# 13614140.

Overall length: 291 mm
Length of larger diameter portion: 92 mm
Please use these written measurements rather than attempting to read the tape measure as Paul had to hold the tape measure and take the photo at the same time.

Disc brake wheel spacer / axle spacer

Thanks to Tom Halchuk, Paul Linn, and Scott Grupe on the old Topica Loopframe_Guzzi news group (which has now moved to Yahoo!). The spacer is part number MG# 13615641.

Tom reports the width of the disc brake wheel spacer is 40.8686 mm or 1.609". Paul reports a slightly different measurement of 40.91 mm. Perhaps the length when new is 41 mm and the spacer is compressed somewhat with repeated torqueings of the axle nut.

The outside measurement is 25.55 mm (1.0035") with a wall thickness of 2.70 mm (0.095"). Scott reports that you can easily make a replacement spacer out of commonly available black iron pipe commonly available at hardware stores. 1" OD pipe is the correct diameter and wall thickness and only needs to be cut to length.

Disc brake fork shroud / headlight ears

Thanks to Paul Linn for providing me with these photos and measurements. The left shroud is part number MG# 13496241. The right shroud is part number MG# 13496141.

The drum brake shroud measures 13 7/8" in length.
The disc brake shroud measures 14 3/4" in length.
Please use these written measurements rather than attempting to read the tape measure as Paul had to hold the tape measure and take the photo at the same time.

Moto Guzzi Loop Frames - Brakes

Table of contents

Brake adjustment

Drum brake adjustment with wheel still on bike