Like most things in life, these differences are not absolute. There was plenty of crossover as the models evolved and there are many exceptions. But, this can serve as a general guideline. Some of the photos and information came from Dave Otis' old website. I'm certain I missed something, so please contact me with any corrections, contributions, or additional photos: greg>at<thisoldtractor.com.
Special thanks to Mike Tiberio, Rob Prins, Newtin, Paul Linn, and Charlie Mullendore of Antietam Classic Cycle for providing additional difference information.
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V7 / V700 |
Ambassador |
Eldorado |
| Engine Case |
3 shallower verticle ribs 
|
most had 3 deeper verticle ribs plus additional diagonal rib running rearward from cylinder base 
very late had horizontal webbing
|
horizontal webbing
|
| Bore |
80 mm |
83 mm |
83 mm |
| Stroke |
70 mm |
70 mm |
73 mm |
| Displacement |
703.717 cc |
757.486 cc |
844.05 cc |
| Piston rings |
4, 3 above wrist pin, 1 below |
4, all above wrist pin |
3, all above wrist pin |
| Valves |
38 mm intake and 34 mm exhaust |
40 mm intake and 35 mm exhaust |
40 mm intake and 35 mm exhaust |
| Valve springs |
Single |
Dual |
Dual |
| Compression Ratio |
9:1 |
9:1 |
9.2:1 |
| Maximum RPM |
6000 |
6500 |
6500 |
| Horsepower at maximum RPM (SAE) |
50 |
60 |
64 |
| Cylinder head exhaust port |
No boss for future exhaust studs 
|
Early models had no boss for future exhaust studs; later models had a boss for later exhaust studs
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Most had no boss for future exhaust studs; Some had a boss for later exhaust studs
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| Cylinder head top stud |
One piece design with o-ring 
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Early models had one piece design with o-ring; later models had two piece design with crush washer
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Two piece design with crush washer
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| Valve covers |
early models had "Moto Guzzi" printed below raised area, no ridge on raised area, longer hex-head securing bolts 
later models had "Moto Guzzi" printed on raised area, no ridge on raised area, shorter allen-head securing bolts
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"Moto Guzzi" printed on raised area, no ridge on raised area, shorter allen-head securing bolts
|
early models had "Moto Guzzi" printed on raised area, no ridge on raised area, shorter allen-head securing bolts
later models had "Moto Guzzi" printed on raised area, ridge on raised area, shorter allen-head securing bolts
|
| Gas tank - capacity |
4.5 gallon |
early models had 4.5 gallon
late models had 5.84 gallon |
5.84 gallon |
| Gas tank - petcock position |
petcocks positioned forward 
|
early models had petcocks positioned forward
late models had petcocks positioned rearward
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petcocks positioned rearward
|
Gas tank - tunnel width
Thanks to Karl Kologiski for providing this difference information. Note: Wider tunnel tanks will fit on the earlier models. Narrow tunnel tanks will not fit on the later models. |
narrow tunnel 
|
early models had narrow tunnel
late models had wider tunnel
|
wider tunnel
|
| Gas cap |
cap with lever, lever secured via special boss on tank 
|
early civilian models had cap with lever, lever secured via special boss on tank
later civilian models had a cap with a lever, lever secure via ring and groove on neck
police models had a screw-on cap, taller neck
|
civilian models had a cap with a lever, lever secured via ring and groove on neck
police models had a screw-on cap, taller neck
|
| Front brakes |
twin leading shoe
|
most had twin leading shoe
some very late models had four leading shoe (circa 1977) |
most had twin leading shoe
some in 1973 had four leading shoe
late 1973 and 1974 had single disk |
| Rake |
27° |
27° |
27° |
| Trail |
56.94 mm |
81.94 mm |
81.94 mm |
| Triple tree offset |
90 mm 
|
70 mm 
|
70 mm
|
| Transmission speeds |
4 speed |
4 speed |
5 speed |
| Transmission gear ratios |
1:2.230
1:1.333
1:0.954
1:0.750 |
1:2.230
1:1.333
1:0.954
1:0.750 |
1:2.000
1:1.388
1:1.047
1:0.869
1:0.750 |
| Transmission case |
Smooth |
Smooth |
Ribbed |
| Transmission gear design |
Earlist all straight cut, middle first straight cut/second-fourth hellically cut, latest all hellically cut |
All hellically cut |
All hellically cut |
| Rear drive gearing |
8/37 |
8/35 |
8/37 |
| Rear drive case |
Polished starburst |
Polished starburst |
Deeper sump and not polished |
| Overall gear ratios (from engine through transmission to rear drive) |
1:14.180
1:8.473
1:6.063
1:4.768 |
1:13.413
1:8.015
1:5.735
1:4.510 |
1:11.424
1:7.929
1:5.980
1:4.964
1:4.284 |
| Carburetors |
Dell’Orto SS1 29mm; later models had an intake liner to increase air flow velocity |
Dell’Orto VHB 29mm |
Dell’Orto VHB 29mm |
| Carburetor body to intake manifold clamps |
Smooth polished aluminum band 
|
Early models had smooth polished aluminum band
later models had steel bands perpendicular to the carb body 
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Steel bands perpendicular to the carb body
|
| Shifter design |
Most had heel-toe, few had toe only |
Most had heel-toe, few had toe only |
Heel-toe |
| Shifter location |
Right side, had a different bend to clear the swingarm nut 
|
Left side |
Left side |
| Rear brake design |
Aluminum 
|
Chrome plated steel 
|
Chrome plated steel
|
| Rear brake plate |
Shaft at 12 o'clock, shoe pivot doubles as tie rod attachment point 
|
Early had shaft at 12 o'clock, shoe pivot doubles as tie rod attachment point
later had shaft at 3 o'clock
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Shaft at 3 o'clock
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| Rear brake location |
Left side |
Right side |
Right side |
| Shift pattern |
1 up, 3 down |
1 up, 3 down |
1 up, 4 down |
| Headlight |
Deep shell |
Shallow shell |
Shallow shell |
| Tail light |
Had additional horizontal mount to the frame, round lens 
|
Early models had additional horizontal mount to the frame, round lens
Later models lacked additional mount, round lens
|
Early models lacked additional mount, round lens
Later models had a rectangular lens
|
| Instrument panel |
Civilian models only had a speedometer See civilian and police variations here |
Early civilian models only had a speedometer; later civilian models had speedometer and tachometer See civilian and police variations here |
Civilian models had speedometer and tachometer See civilian and police variations here |
| Side covers |
Narrow, non louvered |
Early models had narrow, non louvered; later models had wider, louvered |
Wider, louvered |
| Tool boxes |
Knobs 
|
Early models had knobs; later models had locks
|
Locks
|
| Coil |
Magneti Marelli |
Early models had Magneti Marelli; later models had Bosch |
Bosch |
| Coil mount |
Across the frame |
In line with frame |
In line with frame |
| Civilian frame |
Narrower backbone (later tank will fit on earlier frame, but not vice versa) |
Wider backbone |
Wider backbone |
| Police frame (in addition to civilian frame differences) |
Siren mount (mechanical sirens had different mounts than electrical - not sure of difference???), stronger gusset plate for seat, gusset plate drilled for rear crash bars, dimple in rear fender mount at the rearmost part of the frame |
Siren mount (mechanical sirens had different mounts than electrical - not sure of difference???), stronger gusset plate for seat, gusset plate drilled for rear crash bars, dimple in rear fender mount at the rearmost part of the frame |
Siren mount (mechanical sirens had different mounts than electrical - not sure of difference???), stronger gusset plate for seat, gusset plate drilled for rear crash bars, dimple in rear fender mount at the rearmost part of the frame |
| Generator |
Magneti Marelli |
Early models had Magneti Marelli, later models had Bosch |
Bosch |
| Generator covers |
Two individual metal plates (most painted, there is some debate as to whether or not some were chromed) 
|
Early models had two individual metal plates (most painted, there is some debate as to whether or not some were chromed)
later models had a single black plastic cover
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Single black plastic cover
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| Regulator |
Magneti Marelli |
Early models had Magneti Marelli; later models had Bosch |
Bosch |
| Starter |
Magneti Marelli |
Early models had Magneti Marelli; later models had Bosch |
Bosch |
| Center stand |
Short feet |
Early models had short feet; later models had long curved feet |
Long curved feet |
| Turn signals |
None |
None |
Front and rear |
| Fender reflectors |
None |
Early models had none; later models has reflectors with wide chrome trim; some very late models had reflectors with very narrow trim |
Early models had reflectors with wide chrome trim; later models had reflectors with very narrow trim |
| Fork covers / headlight ears |
Shorter |
Shorter |
Shorter for all drum brake models. Disc brake models are longer. |
| Swing arm |
Aluminum cap on the back end of the swing arm...just before the rear drive |
Boss that could be drilled for aluminum cap |
No boss. |
| Hand levers |
Smooth lever with a perch that angled toward the handlebar 
|
Early models used a smooth lever with a perch that angled toward the handlebar
later models used a finger-grooved lever with a perch that was more square to the handlebar
|
Finger-grooved lever with a perch that was more square to the handlebar
models with 4 leading shoe front brakes used a finger-grooved lever with a special adpater to connect both front brake cables
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Shocks
Thanks to Newtin for providing this difference information. Note: the shocks must be completely disassembled to remove the chrome cover; the plastic cover can be distorted to clear the tabs at the bottom of the shock body. |
Early models had a black plastic inner cover to hide the rod 
later models used a chrome steel cover to hide the rod
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Early models used a chrome steel cover to hide the rod
later models had a black plastic inner cover to hide the rod
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All used a black plastic inner cover to hide the rod
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