New bolts for 2x10?

Wormishere1
Wormishere1 Posts: 284
edited April 2014 in MTB buying advice
Hi,

Looking to convert my 3x10 XT to 2x10 - moving from 22-30-40 to 22-36. Will I need new chainring bolts or will I be ok with the original Shimano bolts on it at the moment?
Remember Rule #5

Comments

  • jimothy78
    jimothy78 Posts: 1,407
    You'll need new (shorter) bolts for the new 36T ring, as the bolt will only be passing through one ring and the crank spider, instead of two rings.

    Alternatively, you could fit a bashring in place of the outer ring, which would mean you could use the old bolts.
  • Wormishere1
    Wormishere1 Posts: 284
    OK, which ones of these would I need then?
    http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... TQ:GB:1123
    Will it be the single?
    Remember Rule #5
  • rickbst170
    rickbst170 Posts: 228
    Or use m10 washers. I brought a bunch home yesterday but nothing suitable. M10 spring is good depth and width but the bolt head is too small to compress the spring washer. It would be ok with an m8 flat behind it, but then bolt too short. Flat M10 I have are good depth but too wide and foul on crank arm and chain.

    I'll have another look in my washer box, and failing that, file down originals by 1-2mm (stick in a drill and offer up to flat file).
  • rockmonkeysc
    rockmonkeysc Posts: 14,774
    Those on ebay are expensive. I got a set of ethirteen chainring bolts for a bit over £5 from my local shop.
    Any single ring bolts will do the job.
  • Wormishere1
    Wormishere1 Posts: 284
    Thanks - had a look for some ethirteen ones but they all come up as more expensive, you must have got a bargain!

    Not thought about washers but sounds like a good idea too - will wait for my LBS to get me in a 36t Shimano chainring first...
    Remember Rule #5
  • Wormishere1
    Wormishere1 Posts: 284
    jimothy78 wrote:

    I saw them and would much prefer them to keep my cranks looking tidy, but they are made of plastic by the sounds of it and have got a fair number of poor reviews. RaceFace also make a similar product in aluminum but is out of stock everywhere!
    Remember Rule #5
  • mcnultycop
    mcnultycop Posts: 2,143
    Onza single ring bolts on eBay are cheap and colourful.
  • rickbst170 wrote:
    Or use m10 washers. I brought a bunch home yesterday but nothing suitable. M10 spring is good depth and width but the bolt head is too small to compress the spring washer. It would be ok with an m8 flat behind it, but then bolt too short. Flat M10 I have are good depth but too wide and foul on crank arm and chain.

    I'll have another look in my washer box, and failing that, file down originals by 1-2mm (stick in a drill and offer up to flat file).


    you suggest using M10 washers... then say that all the ones that you have tried dont work... :?

    i used these on mine:
    http://www.chainreactioncycles.com/e-th ... -prod66378

    My friend used these:
    http://www.chainreactioncycles.com/bran ... -prod19227

    basically no difference! and you get 5 with the cheaper ones!
  • rickbst170
    rickbst170 Posts: 228
    you suggest using M10 washers... then say that all the ones that you have tried dont work... :?

    Lol, they do exist. They're available here...
    http://www.custom-fasteners.co.uk/acata ... shers.html

    M10 with 17mm OD.

    They're 8p each on that website. If I already have some, I'll use them. The OP might also already have some so plausible solution.

    If not, file or replace bolts.
  • The Rookie
    The Rookie Posts: 27,812
    Depending on the crankset, you'll often have to file a flat on the washer for it to sit flat and not foul the ring location tabs. (been there and done that).
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • rickbst170
    rickbst170 Posts: 228
    Don't be too hasty cutting nuts and bolts. My new chainring turned up yesterday, renthal single ring. It's thicker than the XT middle so doesn't need spacing or shortening. Standard length triple chainrimg bolts fit like a glove.

    IMAG0234.jpg