How Does A Motorcycle Chain Stretch?
Monday, July 26th, 2021
This chain has served me well but now needs to be replaced.
When I got a new tire on the V-Strom the guys at the shop told me the chain was pretty stretched and needed to be replaced. That was no surprise–I’ve had this particular chain for a long time–but it got me thinking. How in the heck does such a large mass of metal stretch? I mean, do the many individual pieces that make up a chain actually get longer?
I decided I would do some research.
One of the first things I encountered was a whole other question: Do new motorcycle chains stretch?
Heck, I wasn’t thinking at all about new chains, I was totally focused on older ones needing replacement. But apparently new chains do “stretch.” That is to say, when a chain is assembled, all the pieces are more or less in place but once they are on a bike and experiencing stress they all sort of fall into functional place and that can result in the chain being a little looser. It is recommended that you do an adjustment after the first several rides with a new chain. Then you should be set for quite a while.
But that’s not the same phenomenon as an old, worn chain.
In the case of an old chain, it turns out it really isn’t the individual pieces getting stretched so much as worn. A chain has all these links that are joined with pins. The pins are projecting through round holes in the links and they are what allows the chain to flex. What wears is the pins against the holes, so these initially round holes get rubbed away so that they are no longer completely round, but become elongated.
That enlarging of the holes effectively allows the entirety of the chain to become just a bit longer. Mind you, we’re talking only a fraction of an inch over the entire length of the chain but it is enough to make a difference. If you want a detailed explanation here’s a good video.
Now, I know the V-Strom needs a new chain and sprockets but I figured all along that would have to wait until after I get back from the upcoming OFMC trip. I hope that is not going to be any kind of problem because it’s looking more and more like I may be riding the V-Strom on the trip. I was hoping Joel would have the Concours ready in time but that is starting to look doubtful, although I’m still awaiting the final word from Joel. I’ll go into that issue in my next post.
Biker Quote for Today
My motorcycle had a small oil leak. And thanks to my lack of mechanical skills, it now has a giant oil leak.
