peters@cubsvax.UUCP (Peter S. Shenkin) (01/21/86)
I just replaced my chain, after finding that it still felt gritty after cleaning (that is, it felt like there was grit in the bearings). I had hung my old chain up to dry, and instead of counting links, I hung my new chain beside it, expecting to be able to match ends, and therefore not have to count links. I was amazed to see that after lining the chains up carefully at the top, the new chain was noticibly shorter than the old one even a foot down. In fact, in 40 inches of length, the new chain was shorter by a full link spacing, i.e., 3/4 in. This comes out to (3/4)/40=0.019, or 1.9%. That doesn't sound like a big percentage, but consider that 40in of chain has about 53 links in it, so it will approximately fill a 52-tooth chainwheel a full circle around. A chain stretched by 2% is stretched roughly to the point that 51 links, instead of 52, fit around such a chainwheel. I haven't gotten back on my bike yet, but it'll be interesting to see whether I can still shift, or whether I have to replace chainwheels and/or cogs. Incidentally, the chain had less than 1000mi on it, but much of my riding was fully loaded in sandy land. My old chain was a DID-Lanier and the new one is a Sedisport, but this shouldn't matter. By the way, when I bought the new chain I also decided to invest in a Vetta chain cleaner. Live and learn. And while I was at the shop, I picked up a pair of the new Diadoro touring shoes; haven't used them yet, but they're beautiful, and very comfy. (My old shoes literally fell apart on my Florida trip.) Cheers, Peter S. Shenkin, Columbia Univ. Biol. Sci. philabs!cubsvax!peters cubsvax!peters@columbia.ARPA