After giving my drivetrain a bit of a overhaul I decided to put a bigger chainring on. When I put it on it wasn’t running straight and was moving out laterally ever so slightly. It was an old chainring so thought it must be bent. I’ve now put the old original one back on and that is also wobbly.

As far as I can tell the chainring is straight. Si figure it must be the cranks but they also look straight! The cranks are Race face ride. I can’t get my head around it.

Anyone else else experienced this? Any tips? Does anyone know what the problem might be?

Video?

How much out is it?
Are you sure it’s not just the profiling of the teeth making it look out?

Can’t you just magic it back again?

Molgrips – i’ll try and get a video up tomorrow.

adam@bikeworks – It’s a good few mm’s out. Also when I jump on the bike and pedal under force I can feel the chain trying to come off the front ring.

is the crank on straight and bolt done up tight?

There’s often a bit of leeway on loosening & retightening but I doubt you could correct a “good few mm”

bruneep – I think so, but I’ll take it off and double check. I’m wondering if I’ve overtightened some of the chainring bolts too.

Bent crank tab? (had this on whatever the cheapy cranks are on my commuter, I bullied them straight with a big crowbar, probably a terrible idea…)

I’ve seen loads of chainsets a few mm out.

Cynic-al +1

Its ok, wonky rings are all the rage right now, its lateral biopace!