Chain "skipping"

Hey guys,
I'm getting close to getting my first build complete but am having problems with the chain for the engine.

Basically what I'm seeing is that the chain "skips". I've been testing it by trying to ride the bike with the clutch depressed (trying to make sure it works fine as a bicycle before worrying about actually starting the engine up).

As I'm riding the chain will make a loud noise fairly often. From turning the bike over and spinning the wheels I can see it's because when the chain goes through the engine's sprocket, occasionally the hole in the chain isn't quite aligned with the tooth of the sprocket, causing it to jump a bit.

I tried removing the wheel sprocket and putting some duct tape around the wheel hub to fill the extra room and to eliminate any possible play to make sure the sprocket was exactly in the center and not uneven, but I'm still seeing the issue.

Any other thoughts on how I can debug this?

Thanks

2door said:

Chain tension is important. You'll want 1/2 to 3/4" slack in the chain. Alignment is also critical. Viewed from rear to front the chain must be aligned to the drive and driven sprockets as well as the tensioner wheel if used. Check your chain for any binding links that can cause a chain to not properly follow the curvature of the sprockets.

Some sprocket teeth are rough on their out ends. This can cause the chain to bind and jump as it goes over the sprocket. The rough edges can be filed or ground off with hand or power tools. A Dremel tool comes in handy for a lot of things. This is one of them.
Good luck.

Tom

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Thanks for the quick reply, 2door!

I think the slack in my chain is good. Maybe alignment is my problem though. I put a level along side the engine sprocket and the wheel sprocket and can see that they're not both along the same angle...I'll try and fix that (hopefully it's just that the bolts on the wheel sprocket aren't evenly tightened) and see how things look.

As far as the teeth, I'll have to take a look at that as well...

I've made some adjustments and it seems much better...how much skipping should I expect? Absolutely none? It seems like it still skips a bit here and there but overall things seem much smoother when I've got the bike upside down and I spin the wheels.

I'll give it a ride as well, see how that feels.

EDIT: I think I spoke too soon; still seems to be skipping a lot. I'm tempted to start with my wheel sprocket being a bit uneven, although it's hard to tell by sight. I can see though that the chain moves across the wheel tensioner at an angle, guessing that's no good but it could be the tensioner that's off.

Thanks again for the reply, 2door.

I made some more adjustments and think it's looking good! I just took it out for a spin and it cruised along real nice

Now I'm sorting through solutions for my gas tank mount since my tube is too big. Came across your reply about the double-sided tape but not quite sure I'm getting the whole picture. Maybe I should reply to that thread... (http://motorbicycling.com/f34/gas-tank-brackets-30462.html)