7 to 8 to 9 speed

FOGcp
FOGcp Posts: 145
edited June 2007 in Workshop
My wife has a hybrid that she insists is perfect for her so even though the gears are knackered she insists I replace them rather than buy a new bike--hence my question . Her hubs are 8spd Deore with a spacer to make them 7spd. Can I drop spacer and use 9spd cassette and chain or am I forced to use 8spd components. I know I will have to replace mechs and shifters to suit which is why I think she should buy a new bike.

Comments

  • Phil Russell
    Phil Russell Posts: 1,736
    Depending on the value of your wife's bike, a new bike could well be the way to go as it could be much cheaper than a complete new drive train to upgrade the gears.
    But what parts are worn on the 7 speed?
    I advise you to cost out the various options ... either at your lbs or via a web site such as SJSC or ribble etc.
    Cheers, Phil
  • Steve I
    Steve I Posts: 428
    Yes, you can fit a 9 speed cassette and chain. The 8 and 9 speed Shimano cassettes are the same width, hence the narrower sprockets and chain on the 9 speed. I presume the bars are straight, if so you should be able to pick up a 9 speed shifter quite cheaply, I got one from Merlin cycles in Leyland. You shouldn't have to replace the rear mech., it should work fine with some adjustment.
  • john_wr
    john_wr Posts: 50
    I use a tatty old frame with hand me down parts as a sort of shopping bike or out for rides with my wife. It has the following set up in the transmission. Twist grip 7 speed shifters - 8 speed Shimano STX rear mechanism - wheels built on Campag chorus hubs ( well past their best ) with Campag 9 speed cassette - unknown make of 8 speed chain. Because of the 7 speed shifters I don't use either the smallest or the largest sprockets. I was admittedly quite surprised when I assembled the drivetrain and found it worked, with gear selection being quite positive. My advice is if you have any access to old but still usable parts, then fit them and see what happens.

    Cheers

    John
  • maddog_2cp
    maddog_2cp Posts: 73
    wheel will be fine. Just need:

    new 9spd cassette
    new 9spd chain
    new 9spd shifters

    rear mech should be fine
    front mech should be fine. If it's a triple then you may find the shifting a tad sloppy due to the 8spd cage being a bit wide for the new narrower chain.

    chain and cassettes wear. No need to chuck the bike.

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    Drop bars are a historical accident...... discuss
  • sjcpcp
    sjcpcp Posts: 604
    You don't even need the 9-speed chain. I've used 8 and 9 speed chains on my 9-speed bikes and haven't noticed any difference. So I now use 8-speed chains all the time, as they're cheaper.