Bicycle Mechanics - Is my chain too short?

Hello there,

Sorry to fire this off w/o doing proper background work. Would this account for the derailleur body hitting the swingarm?

I've never really had to mess with a rear derailleur before.

Thanks in advance. :)
Cheers

if the swingarm thing is hitting the body of derailleur at any point, your chain is too long. By that i mean the singwarm is essentially backing into the body

That's funny... chain might be too short, try adding a few links see if it helps, but that swing arm is massive.
I cant imagine how shortening the chain would help in this case....

Hello there,

Sorry to fire this off w/o doing proper background work. Would this account for the derailleur body hitting the swingarm?



From looking at the position of chain, both front gears and rear cogs, the length of chain seems to be about right. It's more like caused by the combination of width of the swingarm and the chain tension which comes from the spring of the pulley arm. I imagine it'd be hard to find stronger spring that fits your derailluer. I would try to find something that protects the swingarm that you can find in hardware store that can be easily replaced, only if it bothers you.

Thanks guys for the input, conflicting as it may be. I will have to go through the procedure for chain sizing.

My first thought was to just put a pad on the swingarm but I would like to set it up correctly.

Other than the contact issue it isn't shifting correctly either. My smallest five cogs are no problem, but there's a lot of tension through the shifter going onto the third biggest and it won't go onto the two biggest ones at all.

Cheers

Just looking at the photo it doesn't look to me like you have a problem. You might try the mountain bike forum if you can decipher their answers.

Working on suspension bikes is a little bit different. When that photo was taken nobody was sitting on it. When you sit on the bike the suspension is going to sag and I think that your problem will solve itself.

I use the big/big method of sizing chains. Wrap your chain around the big/big sprockets bypassing the derailleur. Add 1 inch of chain. It's really important on a mountain bike to have enough chain to cever the big/big combination because you can be surprised by a short uphill sometime when you're in the big chainring and try to force a shift to get up it. That can be an expensive mistake if your chain is too short.

Well it's too short, but only for the big ring, which I'm not using.

It's more of a B spring tension thing. If only it generated a bit more tension. I'll play with it next. My first thought is to try to just wrap it up tighter. We'll see when I dismantle it.

I fear some, if not the majority of the problems are from a crapped out derailleur in general. That arm is a little sloppy, but I have no reference point.

Thanks for all the input. Much appreciated.

Cheers