4Rings6Stars

I recently picked up a Cannondale R800 with a tricolor group. The bike had been neglected but I replaced a few things, cleaned, lubed and repacked and this is how it sits tonight.

The chain is rubbing the cage on RD. I've tried adjusting and fiddling with it but to be honest, I'm still a hack bike mechanic and I'm not sure what to do. This is the first time I've run into this in my short (10 months now) time with road bikes. Is it possible that the chain is too long or that maybe there is something wrong with the derailleur itself and not just the mechanic?




(mind the bike parts/tools scattered across my floor and the strange four-legged creature roaming in the background)

Glennfordx4

By looking at the photos it looks like the chain is to long, when you put the chain on the big sprockets both front and back without going through the RD you should only have one inch of chain extra(one link). Looks like someone didn't cut the chain right should be a easy fix.

5cagm

+1 to that

khatfull

Pull a link. See how it does small to small and big to big. Might have to yank two. But, that's your problem. Had the same thing when I switched from a 42T small ring to a 40T when in the small small combo. RD rubbed in the exact place. Took out two, that was too many for the big big combo, added one back, happy happy joy joy.

Second to last pic...chain is drooping...definitely your problem...

rccardr 

...and while you're at it, clean that rascal up and replace the derailleur cables. But crank in the RD adjuster a bunch when you puton the new cable. Housing for the rear cable is a short section of brake housing, oddly enough- replace that too. You'll find that a reasonably clean Tricolor drivetrain with new cables that's been properly adjusted shifts as sweetly as just about anything out there. Well, with downtube shifters, anyway.

miamijim

A few issues at play here....

1. FD is sitting up too high on the frame. With the right crankarm at its lowest point while in-line with the seat tube you want a nickles amount of space bewteen the chain ring and the FD.
2. As others have said the chain is a link too long. I tend to size my chains in the small/small combo. Lengthen it until it rubs like yours then remove a link.
3. Looks like the 'D' screw is cranked all the way in to compensate for the long chain. Back the 'D' screw out as mich as possible.

RobbieTunes

Can't take out one link.
Gotta take two.

Homebrew01

Depends how you count them.

In that case take out 4 or 6, not 2. OP's still on the 15t cog or so.

Wogster

I bet what happened is someone replaced the chain and didn't cut it to the proper length. A chain link is actually a sort of double link, if you look at it you will see that there are two widely spaced plates then a roller, then a set of narrow spaced plates, and another roller, then the pattern repeats. You can't join wide to wide or narrow to narrow, so if you break with wider plates on the left, and narrow on the right, then you want the next break must have wider plates on the left and narrow on the right, so you can join it back together. First though look for an open-able link, they go by various names like quick link, super link, etc. If there is one, then you add or remove links at that point. If it doesn't have an open-able link, then you should probably add one, they look like this then you cut your chain so that you have narrow plates on both sides and this replaces the wider plates at the joint. This means that if you want to remove the chain for some reason, you just find your quick link, and open it. Oh, before you toss those extra links, pop them into a small container (35mm film cans or a pill bottle), then shove it into your bike bag. If you break down with a busted chain, then you take out the broken link(s) and put in from your spare link(s).