Time for a New Chain
Yesterday, I realized I hadn’t replaced my chain in some time: I think I was in Ely, NV last time I replaced it, so I biked to the closet bike shop to get the chain wear checked.
In order to get to said bike shop, I had to go through Tysons Corner. Suffice it to say, I was the only bicyclist on the road, but with Tysons attempting to become a transit oriented urban center, perhaps I’ll soon find more bicyclists on the road there. In any case, I learned that my new lights work pretty well since I got honked at a lot.
When I arrived at the bike shop, a nice mechanic checked the length of the chain and said that I should replace the chain, but the freewheel is still O.K. since the chain had not lengthened to the point where the freewheel sprockets are machined by the overly lengthened chain. Note that I used lengthened instead of stretched. I recently learned that the lengthening of chains is caused by the chain plates slowly grinding away at the rivets creating a gap between the plates and the rivets. Lengthening is not caused by the stretching of the plates themselves.
I left the shop with a new chain in hand and rode home to install it. I took off the old chain and instead of using the old chain to measure out the new chain, I measured the length of the chainstay (center of crank bolt to center of axle), and punched that number along with the number of teeth on the biggest sprocket in the front and rear into an formula for chain length which yielded a length of 55 inches. Since each link is a half inch and the chain came with 114 links, I figured I needed to remove 4 links, but just to be sure, I measured.
Once I took out the links, I put the chain on, connected the master link and checked to make sure the chain was neither too short nor too long.