Shimano indexing problem

R25 Flyer
R25 Flyer Posts: 47
edited November 2008 in The workshop
Hi there. I had a puncture yesterday and after replacing my wheel noticed that the indexing was a little out with the chain slipping from 4th to 5th on the large chain ring without my asking!

I have Shimano 105 derailleurs, 10 speed casssette (11-25), a compact chainring (50-34) and chain operated by Deore XT rapidfire shifters. Last night I played with the indexing and thought I'd got things ok. The problem I have is that if I get the indexing sweet for the big chainring I have trouble shifting to smaller cogs on the small chainring and if I get the small chainring shifting sweetly, I struggle to get the shift to a larger cog on the big chainring.

Is this something I have to live with? I've tried to strike a balance to get into work. I'm confident that the cable is ok as the derailleur moves fine with the clicks. Is it perhaps something to do with running a compact and the change in angles? Any advice would be very welcome.

Thanks.
R25

Ridgeback R25 - 1% bike

Comments

  • cjcp
    cjcp Posts: 13,345
    No responses! Wow!

    Gears are one of the dark arts - I hate them.

    When you say you played with the indexing, did you just tweaked it using 1/4 turns etc to try to fine tune it or use bigger turns?

    If all else fails, visit LBS. It's won't take them long. I don't see why the shifting between the 34 and 50 should cause a problem if it was fine before. Is it a new bike? Just wondering if you're gears need a tune if they've settled in.
    FCN 2-4.

    "What happens when the hammer goes down, kids?"
    "It stays down, Daddy."
    "Exactly."
  • cjcp - thanks for the reply.

    I was following my Haynes manual to try to set them up. At one point I was going more than the 1/4 turns to try and get the chain skipping up a cog and then had to come quite a bit back down to get them down again. Trip to LBS this weekend I think. As you say it won't take them long and Mrs R25 will be glad the bike's not upside down on the kitchen floor again.

    Dark art indeed.
    R25

    Ridgeback R25 - 1% bike
  • nicklouse
    nicklouse Posts: 50,675
    not a problem that you have to live with.

    Please note that you should not be using the extreme cog combos.
    Also i do not belive that you have a 10spd cassette and XT shifters.

    If you do the you will always have problems as XT is 9spd only.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Wow nicklouse - you are truly a bike genius. 8) I had assumed that since the shifters appeared to be part of the brake lever unit that they were XT as well but have just checked the spec and the shifters are actually Shimano SL-R770 which as we all know are 10 speed. :)

    I tried to give as much info as possible and just managed to cabbage myself in the process.
    R25

    Ridgeback R25 - 1% bike
  • nicklouse
    nicklouse Posts: 50,675
    back to the problem.
    is sounds more like that you need to give the cables some Lurrve.

    get lubing.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • neiltb
    neiltb Posts: 332
    could just be a chain alignment issue, why would you be on 4th sprocket on large chainring?
    FCN 12
  • fossyant
    fossyant Posts: 2,549
    Cables is where I would look - replace or clean and lube !!!