Chain Frustration

[dougsr.874]

I have been involved in this hobby for several years and I thought I knew quite a bit about these 2 stroke kits....Today I tried to replace a chain for a customer and discovered quite a problem....I purchased some replacement chains a few weeks ago but today I found something amiss withe these chains.....to make a very long story short, when you roll the replacement chain onto the front sprocket about every 4th link rides on top of the sprocket tooth. I even replaced the sprocket but same problem....So, I guess my question is: Is the length between the links of a chain the same on a 410, and a 415 chain......I robbed a chain from a new complete kit I keep on hand and that chain worked fine.....What's wrong with the replacement chains I have??????? Is it a mfg. defect or what....

 

[Fabian]

That's because their appears to be metric 415 chain and imperial 415 chain, which have slightly different pin to pin lengths. Although they're both supposed to be the same, they are not the same, and i've had the same problem as you have described.
The 415 chain supplied with the SickBikeParts shift kit works perfectly on the 415 sprockets, but a replacement chain from an aftermarket chain supplier was slightly mismatched as were other chains from different retail outlets in Australia.

Having said that, it's an easy problem to overcome: running new chain on old sprockets for about 50 miles (giving the chain time to slightly stretch) then installing new sprockets.

Problem solved and job done!

 

[dougsr.874]

Thanks very much for the info.....But, how are you supposed to run the bad chain on an old sprocket when the chain locks up before you can even get it on the front sprocket....???

 

[darwin]

If the chains pitch doesn't work you need the correct chain. Return the incorrect chain and get the correct one or change sprockets. No compromises to it.

 

[Fabian]

If you have an old chain mismatched on old sprockets, then either the chain or sprockets are not designed to work with each other in the first place.

The mismatch between metric and imperial 415 chain is almost insignificant, but when new, it's enough to make the chain ride the sprockets, for about 10 miles, and after 50 miles it's settled in nicely.