TOPIC:

Im refurbishing a '74 z1 , it had a 37 tooth aftermarket sprocket no spacer , how do i know if i need the spacer with my new sprocket ?

If you're talking about the thin spacer that goes between the sprocket and sprocket carrier, the spacer is needed if you're running an O-ring chain.. A matching spacer is needed for the countershaft sprocket too, to maintain alignment. Some aftermarket countershaft sprockets had the spacer machined into one side, so they could be used with either type of chain.


Good Ridin'
slmjim & Z1BEBE

Haven't used one for years.
Steve

SWest wrote: Haven't used one for years.
Steve

If you're running 630 o-ring chain with an early sprocket (no shoulder) your chain will rub on the outside of the tranny cover. The purpose of a shoulder on the sprocket is to provide clearance for the extra width of an o-ring chain.

hardrockminer wrote:

SWest wrote: Haven't used one for years.
Steve

If you're running 630 o-ring chain with an early sprocket (no shoulder) your chain will rub on the outside of the tranny cover. The purpose of a shoulder on the sprocket is to provide clearance for the extra width of an o-ring chain.

Yup. We've seen many tranny covers scored because of that. Lots of metal shavings in the grunge surrounding the countershaft sprocket.

Seems like Mama Kaw made a shim for the countershaft for that too? We'd have to dig through the Service Bulletins...


Good Ridin'
slmjim & Z1BEBE

Yep! I have one with the score marks. The chain actually rubbed the head off one of the tranny cover screws too.

My sprockets come with the shoulder. Even then it's a tight fit. Been thinking about using washers to space the rear sprocket instead of buying a NOS from a eBay SHARK.
As I said I haven't been running one for years. No problems.
Steve

It's not necessary to use a stock one on the rear but whatever is used...it needs to be at least the same diameter as the sprocket bolts or there is a risk that the bolts will "bend" the sprocket when torqued up.

Using nothing is kind of like having high blood pressure and not taking medication. You won't notice anything different but there will be wear on the sprocket and chain due to misalignment.

No misalignment. The most important part is the countershaft sprocket.
Steve

There would be misalignment if the front sprocket had a shoulder (as the photos show) and the rear sprocket didn't have the spacer specified in the parts manual. When KHI switched to O-ring chain they added both, along with a re-designed chain guard to prevent rubbing. There were other changes made as well. The chain adjusters were narrowed, the muffler mounting bolts were shortened, and I believe the engine mount bracket was modified. All in all it's a great education on all the related things that can happen when something as simple as a chain is modified.

At least 10.000 miles on this one. First a NOS O ring chain, when it developed tight spots a new Gold high performance O ring chain (made in china) then a standard 630 chain until I could afford a whole new setup. See any misalignment marks or undue wear?
The O ring chains are wider inside and out. Plenty of room for it to glide happily doing it's job for 1000's of miles.
BTW, my chain guard was the same as Larry's Z1a and Jim's 73 Z1.
I've had my Z1b 43 years. It's changed after the wreck so I'd like to see some pics of the changes you've described.
Steve

The manufacturing tolerances 45 years ago will smoke off the 1,5 mm spacer!!!