on both of my singlespeeds the chain is tight on 1 position of the crank and 180 degrees opposite its loose. this causes the chain to come off at the worse possible moments... anyways i have a shimano and a raceface both 32t. can anyone recommend a chainring that is actually round, not an oval? also needs to be the shimano 4 bolt as well as 94mm 5 bolt. dont care weather it has ramps on it. thx
Chainrings that are actually round?
- Thread starter Anders
- Start date
That's a very tall order you're suggesting. I actually don't have that problem on my SS but it has been an issue on virtually every BMX bike I have ever owned. I found that if I found some sort of happy medium, I was fine. Keep in mind that this was for horiz dropouts.
Try either Salsa, Surly or the $$ shot is Boone
I had the same problem until I bashed my ring trying to bunnyhop a cement ledge, maybe youcould try that.
ive never had any problems with chain rings.. one thing to check to see if you chain is abnomally stretched. the can stretch unevenly creating tight/loose spots in certain positions. Id clock the chain or chain ring 180* around and check if the tight spots have switched too.
yup its definately not the chain. gonna try and get a surly ring soon
From Sheldon Brown -- http://sheldonbrown.com/singlespeed.html#tension
"If the chain is too tight, the drive train will bind, perhaps only at one angle of the pedals (chainwheels are not usually perfectly concentric). It should be tight as it can be without binding. If the chain is too loose, it can fall off, usually at the most inconvenient possible time.
Set the rear axle so that the chain pulls taut at the tightest part of the cranks' rotation. One at a time, loosen up each of the stack bolts, and tighten it back just finger tight. Spin the crank slowly and watch for the chain to get to its tightest point. Strike the taut chain lightly with a convenient tool to make the chain ring move a bit on its spider. Then rotate the crank some more, finding the new tightest spot, and repeat as necessary.
This takes a little bit of your hands learning how hard to hit the chain, and how loose to set the stack bolts, but it is really quite easy to learn.
Tighten up the stack bolts a bit and re-check. Tighten the stack bolts in a regular pattern, like the lug nuts on a car wheel. My standard pattern is to start by tightening the bolt opposite the crank, then move clockwise 2 bolts (144 degrees), tighten that one, clockwise 2 more, and so on. Never tighten two neighboring bolts in a row. You may prefer to go counterclockwise, but try to get in the habit of always starting at the same place and always going the same way. This reduces the chances of accidentally missing a bolt."
"If the chain is too tight, the drive train will bind, perhaps only at one angle of the pedals (chainwheels are not usually perfectly concentric). It should be tight as it can be without binding. If the chain is too loose, it can fall off, usually at the most inconvenient possible time.
Set the rear axle so that the chain pulls taut at the tightest part of the cranks' rotation. One at a time, loosen up each of the stack bolts, and tighten it back just finger tight. Spin the crank slowly and watch for the chain to get to its tightest point. Strike the taut chain lightly with a convenient tool to make the chain ring move a bit on its spider. Then rotate the crank some more, finding the new tightest spot, and repeat as necessary.
This takes a little bit of your hands learning how hard to hit the chain, and how loose to set the stack bolts, but it is really quite easy to learn.
Tighten up the stack bolts a bit and re-check. Tighten the stack bolts in a regular pattern, like the lug nuts on a car wheel. My standard pattern is to start by tightening the bolt opposite the crank, then move clockwise 2 bolts (144 degrees), tighten that one, clockwise 2 more, and so on. Never tighten two neighboring bolts in a row. You may prefer to go counterclockwise, but try to get in the habit of always starting at the same place and always going the same way. This reduces the chances of accidentally missing a bolt."
I should have known Sheldon would have that on his site. It's not hard to figure out though.lux said:
Also on a BMX it's generally the freewheel that's screwed up, not the chainring.