Acct retrofit

[2WheelFun]

So I have revived my 7400 mile 1979 special, adjusted the cam chain tensioner and valves. Now I hear chain slap when doing a quick release of throttle when in neutral.

So the question is, do you feel like the tensioner should be replaced with a new unit or would a used vmx12 unit for cheap work well for me? I really don't want to spend another $100 on it if it's not necessary.

[DiverRay]

Go with the used vmx12 unit!!! The stock cam chain adjuster is the one weak spot in the XS1100 engine, IMHO. While waiting for the replacement, please do not use the bike. The stock units will not hold the chain against the push of de-acceleration if the threads have started to strip in the 6mm bolt.

[2WheelFun]

Thanks, the original doesn't appear to have any thread issues but like you infer better safe than sorry.

I didn't think the spring would weaken enough to make a big difference to justify a new unit but just wanted to ask the ones in the know.

Right now I see the best deal on the venture unit, will probably go with one of those.

[DiverRay]

The spring isn't a big deal. The ratchet is what keeps the chain tension correct. The spring works when there is little pressure on the chain, under acceleration, and if there is slack it goes to the next notch.