Originally Posted by andylago
ok, cog is good. i pedaled up the biggest hill and walked back down, twice. then tightened the lock ring REALLY tight. turns out the lockring was never being tightened down enough by the guy at the bike shop. he was tightening it without removing the chain, and therefore could not put a lot of pressure on the spanner since it wasn't on straight (chain in the way). i borrowed his spanner and did it myself, with the chain off, and was able to get it like a zillion times tighter. thanks everybody.
hmmm. in my experience, some bikestorefolks don't like trackhubs and fixies and **** and stay away from them... and make mistakes like that.
also, you gotta have a good locknut spanner. some bike toolkits sell real cheap hinged ones that don't give the solid torque you need to firm up a fixie hub.