Chain query - freehub upgrade on Apollo with original crank?

u33db
u33db Posts: 68
edited May 2012 in MTB workshop & tech
Hi,

I have a Halfords Apollo XC26s from a few years back which i use for commuting (yes i know but its fine for my needs).

The rear wheel has buckled and needs replaced but as its a cheapo bike the wheel takes a crappy 7 speed screw on rear cassette.

This limits wheel choice so i'm wanting to convert it to a modern freehub and cassette like my Shimano 105 road bike has (the kind you slide onto the wheel hub not screw on) - the idea being i'll get more wheel choice, a few more gears out of it and also maybe save a bit of weight (if i get something decent like Deore/SLX etc).

Now, i know i'll need to change the wheel, cassette, rear derailer, shifter but i have a question about the chain!

The 105 chain on my road bike is a lot thinner than my Apollo MTB, obviously so they can fit more gears on the cassette. I'm guessing if i get an 8/9 speed cassette for the Apollo instead of the 7 then the matching chain will also be thinner.

My question is will one of these thin/new style chains still work with the current crank i have?

Thanks in advance!

Comments

  • nicklouse
    nicklouse Posts: 50,675
    7and8 speed chains are the same width. But I would always use new with new cogs.

    I would be more concerned about th err drop out width. Spin on hubs tended to be 126mm while a new 8/9spd hub is 135mm.

    Read Sheldons how to on cold setting a frame.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • u33db
    u33db Posts: 68
    Hi,

    Thanks for the reply.

    Its an alloy frame so it couldn't be spread/cold set but the drop out width is fine (pity - good excuse for a new bike!)

    I think i'll spec up some bits for the conversion then


    Many thanks!
  • u33db
    u33db Posts: 68
    Right i got the bike upgraded as follows;

    - new mach 1 rims with deore hubs.
    - 12-25 8 speed cassette.
    - deore rear mech.
    - 8 speed grip shifter to match the original on the other side.

    This has made a massive difference.

    The bearings on the old wheels were pretty knackered so the new ones coupled with the sora cassette have really made it smooth and much faster to ride - very happy!

    Thing is i'm having trouble getting the rear mech adjusted - i spent a few hours on it yesterday and all gear engauge but its still a little rattly...i suspect the cheapo grip shifter are playing apart in that along with my lack of experience adjusting gears.

    This being the case i'm thinking of putting it in somewhere to be setup properly.

    Now, since the deore rear mech is actually a 9 speed unit and the hubs will take 9 speed i'm thinking of coughing up the extra for a 9 speed casette and 9 speed shifters and get everything done at once (as i'd be sure to upgrade to 9 speed further down the line).

    My question is, since 9 speed chains are thinner, can i use a 9 speed setup with my existing crank?

    i.e. are all crank teeth the same width regardless if its a 7/8/9 speed bike?

    Thanks is advance!
  • u33db
    u33db Posts: 68
    Done some more research and the cog spacing on 9 speed triples is slightly different.

    Apparently you can get away with a 9 speed chain on 7/8 speed chainrings but you could possibly suffer the chain skipping across the rings on a dwonshift so i'll leave it for now.

    Swapping to rapid fire shifter with the 8 speed setup instead now which should make things a bit better.