Left shifter question

[tmarcus1076]

Well I'm tooling along at the end of my Sunday morning ride when my rear wheel locks up. It took all my skill to not hit the dirt. Got off the bike and saw the chain stuck between the spokes and the cassette. My front derailleur had shifted to the small ring. The chain was still on the ring. I pried the chain out but there was a stiff link, i'm thinking it is trashed. I limped home the last couple of miles. My question, do you think the left shifter is suspect? I have a mix of 9 and 10 speed Dura Ace parts, 7700 front and rear derailleur and shifters, 7800 crank and sram 10 speed chain. Never had a problem before. I live on Long Island and my rides are pretty flat. I'm thinking I'll remove the front derailleur and just use the big ring till I get it sorted out. Any thoughts. Tony

[ultraman6970]

This thing is shimano and I have no clue about shimano, but... if the chain got off the bigger cog and got stuck between the cog and the spokes, is not a problem of any shifter in 1st place (in second place yes)... the 1st problem for that to happen is that the rd limit screw was in the wrong place, the other problem IMO could be the RD cage that probably is not straight or is the RD hanger being off just enough.

Now, if the shifter has a problem you can pull the cable more than needed and have the problem you got.

Check out your limit screws, besides a dork wheel the screws are the only defense you have in case of any problem over shifting.

[tmarcus1076]

I don't know. I was on the flat and not shifting at all. The front der. just shifted into the small ring. Can't figure what happened.

[cmbicycles]

So you were just riding along in big cog and big chainring then the chain shifted to the small chainring, then chain went into spokes?

[tmarcus1076]

yes

[tmarcus1076]

Let me clarify. I wasn't in the big cog. Maybe two down,

[weisan]

>>Never had a problem before.

Time for some TLC.
Fresh cable/housing maybe.
Tune-up.
Stiff link - might be able to save it if you wiggle it back and forth or sideways to "un-stiff" it.

It's that time of the year ...after months of use and faithful service. Your bike deserves it. :D

[oliver1850]

I agree with U-man. Even if you were in the large cog and the shifter surprised you with an unplanned shift to the small ring, a properly adjusted and functioning RD should take up the slack and keep the chain on the cog.

I could see this happening if you were riding along in big ring and big cog, and the RD low limit screw was out slightly too far. Maybe rattling a bit but won't move to the inside with chain under tension. Sudden slackening of the chain may have let it move off the cog. Weak cage spring could contribute. I've been told that 7700 RDs often have cage springs that weaken with use.

Certainly possible that you have a shifter problem, but I don't think it's the whole issue.

[oldpotatoe]

I don't know. I was on the flat and not shifting at all. The front der. just shifted into the small ring. Can't figure what happened.

Unhook the LH shifter cable..does it still click and pull cable? If it doesn't STI repair kit..flush with WD-40 whilst shifting it then some light spray lube. Were you in big-big combo..as the chain fell to the small ring, perhaps the chain bouncing sent it into the spokes at the rear but certainly check upper/low gear limit screw and der hanger alignment.