Chain tension

[Jferdi03]

So my zeda 80 and the 88 pipe are amazing. Run much better than the unbranded China doll I used before and I like it over the bt100 as well. I've had a lot of issues pop up on my first build, and managed to avoid those on this build. The bike goes very fast, has a ton of torque and out performs what I had before. Now my only issue is I snapped a chain two days in a row. Maybe 50Km between breaks. If its alignment it would be off by a hair. I can't tell with my eyeballs, I doubt this is the issue. Is it likely I had the chain tensioner too tight? How much slack after your tensioner is tightened? Thanks guys. Also is this a better tensioner?

 

[Jferdi03]

Also can anyone confirm for sure a 420 chain will work and not get snagged on the case? Thank you.

 

[darwin]

Purpose of a tensioner is to have no slack in the chain, think of a car fan belt w/tensioner. In the longest span of the chain if you move the chain the tensioner should respond with the same movement. Derailleurs can give you a good example too.

 

[Jferdi03]

Purpose of a tensioner is to have no slack in the chain, think of a car fan belt w/tensioner. In the longest span of the chain if you move the chain the tensioner should respond with the same movement. Derailleurs can give you a good example too.

When I installed the tensioner I did have it as tight as possible, leaving no slack. I usually run Google searched and pull up threads from this forum as well as another whenever I have an issue and I saw people blaming the tensioner being too tight, or loose for snapped chains. Mine definitely wasn't too loose.
Sounds like you don't think it was the tensioner? Could 1-2mm out of alignment be the cause? And when we talk alignment we means the sprockets being straight path to each other right? The sprocket is true, not bent or anything.

 

[Jferdi03]

Put the chain on again with a new tensioner and left the chain no slack at all and it snapped almost instantly

 

[DAMIEN1307]

Put the chain on again with a new tensioner and left the chain no slack at all and it snapped almost instantly

Make it snug, not so tight that the chain has absolutely no give to it...let it breathe a little.

 

[DAMIEN1307]

Put the chain on again with a new tensioner and left the chain no slack at all and it snapped almost instantly

Can you snap a pic of that chain assembly to see what your working with???...DAMIEN

 

[digital_life]

Put the chain on again with a new tensioner and left the chain no slack at all and it snapped almost instantly

If your sprocket is off center and you make it tight in one spot it may be too tight or loose in another, After tightening your chain you should spin the wheel slowly and check the tension as you spin it.

Adjust your chain at the tightest spot or adjust your sprocket to make it centered.
Also make sure your motor is centered and straight

 

[inspectorcritic]

Also can anyone confirm for sure a 420 chain will work and not get snagged on the case? Thank you.

Yes got one on now. Only problem is cutting it, you might need to use a hack saw and you might be able to even use a 440 if you really want to end that problem.
To make sure take it to one of those off-road ATV repair shops have them take a 6" sample roll it around the drive gear to make sure there are no snags.
Confirmed 420.