chain guide as tensioner for SS set-up

cborrman
cborrman Posts: 125
edited October 2010 in MTB workshop & tech
I am converting by heavily upgraded rockhopper to SS, so far have ordererd the gusset cassette replacement and my set-up will be:

SLX super stiff but light-ish crank:

- any recomendadions for replacement chainring bolts gratefully received) will use the middle 32T

- more to the point, can I use somthing like the blackspire BB mount chain guide as a tensioner? http://www.chainreactioncycles.com/Mode ... elID=54360

I believe I heard Ned Overend in this video, say that his SS set-up used a chainguide instead of a tensioner:

http://www.specialized.com/us/en/bc/SBC ... ticle=8497

the bike he is using in the video is the 2011 rockhopper comp 29" which is sold in many markets with gears, so not their eccentric BB version as far as I can tell... so should need a tensioner, I cannot see from video, but can only assume he is running somtheing like this blackspire tensioner???
s-works stumpy FSR, sl2 tarmac, siglespeed rockhopper and a bog standard allez

Comments

  • The Rookie
    The Rookie Posts: 27,812
    Chainring bolts...if you aren't running a bash you'll need shorter for the single chainwheel, I got a set of KCNC (gold bling) off ebay for just over a tenner.....or you can file down the end of the female (outer part) and re-use.

    Simon
    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.
  • ride_whenever
    ride_whenever Posts: 13,279
    You can use a chainguide as a tensioner, but the chain length is pretty crucial to be able to get meaningful adjustment, and you need to be careful that you're not pushing it onto the chainstay.

    I did this on my scott with a 1/2 link chain, works a treat and looks very very tidy.
  • ride_whenever
    ride_whenever Posts: 13,279
    So at the rear i have this:

    4178301151_7f871c5c77.jpg

    and at the front i have this:

    4179061462_11f6338e78.jpg

    So the chain pretty much runs parallel to the chainstay about 1cm away from it.
  • cborrman
    cborrman Posts: 125
    You can use a chainguide as a tensioner, but the chain length is pretty crucial to be able to get meaningful adjustment, and you need to be careful that you're not pushing it onto the chainstay.

    I did this on my scott with a 1/2 link chain, works a treat and looks very very tidy.

    thanks, you mean that the chain will have to be as short as possible in the first place, as if its too long it pushes into chainstay?

    which tensioner did you use, and apologies, whats a 1/2 link chain?
    s-works stumpy FSR, sl2 tarmac, siglespeed rockhopper and a bog standard allez
  • cborrman
    cborrman Posts: 125
    So at the rear i have this:

    ...pics ....

    So the chain pretty much runs parallel to the chainstay about 1cm away from it.

    nice thanks!
    s-works stumpy FSR, sl2 tarmac, siglespeed rockhopper and a bog standard allez
  • cborrman
    cborrman Posts: 125
    Chainring bolts...if you aren't running a bash you'll need shorter for the single chainwheel, I got a set of KCNC (gold bling) off ebay for just over a tenner.....or you can file down the end of the female (outer part) and re-use.

    Simon

    blink is always good :) thanks
    s-works stumpy FSR, sl2 tarmac, siglespeed rockhopper and a bog standard allez
  • ride_whenever
    ride_whenever Posts: 13,279
    Hopefully the idea is clear from the pictures.

    Basically it's not about the chain being short, it's about the chain being pretty tight to begin with. With a chainguide tensioner you can't take a lot of slack out of the chain, which is really bad on the scott because the chainstays are so thick that there's really very little room for adjustment. The 1/2 link chain means that pitch is only 1/2" so there is much less potential slack to have to take up.

    Ideally you want either the gusset bling slink or the slink in 3/32" for ease of use although i'm using a 1/8" chain with some modifications to the setup to allow the top part of the guide to work and the chain to fit alongside the bashguard.

    I had to remove one of the lips on the guide plate because the chain didn't fit through so it is now L-shaped rather than n-shaped and spaced the bash guard out with some 1mm washers.