|   Chainline question (how do you know it's right?) | TexasSS
Feb 3, 2003 7:56 AM | | Hi SSers:
I just built up a Surly 1x1 and love it! I took it on a long (5 hours or so) ride yesterday and it did great. However, when I got home last night and started cleaning it I noticed that the freewheel (Shimano 16t) spins very rough. When I crank the cranks by hand I feel a rough spot which I'm pretty sure is in the freewheel. In fact, if I spin the rear tire backward while the bike is clamped in a stand the pedals move too (not supposed to happen, is it?). I'm wondering if this is a chainline issue.
I'm also getting a bit of creak in either the cranks or the bottom bracket. It's real regular. Comes once in each revolution at the exact same spot. Wondering if this could chainline related, too, or if I just have to tighten my cranks.
My chainline looks fine and I didn't throw a chain on my ride yesterday, but I feel like everything should be smoother in my drivetrain. Any ideas? And hoew do you tell if your chainline is OK anyway?
Thanks in advance! |
| a little help with your confusion | club
Feb 3, 2003 8:19 AM | | if your crank didn't spin backwards when you spin the wheel backwards, your wheel wouldn't spin forward when you pedaled forward. think about it. If, however, your wheel spins backwards when you pedal backwards, then you either have a problem, or a fixed gear -- actually both if you didn't start out with a fixed gear.
your chainline is perfect when the cog is perfectly in line with the chainring so the chain doesn't angle outward or inward at all. you can pretty much see that with yer eyeball, and verify it with a long straightedge held flat against the chainring. beware that if your wheel is in crooked, the cog will not appear to line up with the cog. same's true if your rear triangle is crooked, or your bottom bracket shell is crooked, which is not unheard of.
Is your chain too tight? If you feel a spot of resistance and roughness only once per revolution, always when the cranks are at the same "o'clock," it's probably that your chain is binding at that spot because it's too tight. Rare is the drivetrain that doesn't tighten and loosen slightly per revolution due to a cog, ring, or crank spider that is not perfectly concentric. that, unfortunately, is pretty normal. set your chain tension so it's tight, but not binding tight, at the tightest. |
| agree; to put it more simply.. | SSDunderhead
Feb 3, 2003 9:27 AM | | it sounds like your chain is too tight. As far as the creaking goes there are lots of causes; pedals, chainring, bottom bracket or crank. You'll have to be more specific on all these areas.
OGOG, Brad |
| re: Chainline question (how do you know it's right?) | TexasSS
Feb 3, 2003 1:53 PM | | Thanks guys. I have noticed that my chain is very tight. I'll bet that's the culprit. I'll move the rear wheel up a little and see if that provides the slack I need.
Thanks again! |
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