Bicycle Mechanics - 7 sp cassette on 8/9 sp compatible wheel

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Gawain
11-18-07, 01:18 AM
Hi guys,

My commuter's old wheels have failed after 15 years of reliably serving me. Can I buy any new 8/9 speed compatible wheel and just put a spacer to adapt it to my 7 speed cassette? is it that simple or is there anything special I should pay attention to?

Thanks in advance,

mtnbiker4791
11-18-07, 02:00 AM
7 spd cass will fit 8/9 spd wheel just need a 4.5 mm spacer to fit it on.
Retro Grouch
11-18-07, 04:49 AM
Couple of things.

1. What's the distance between your dropouts? A new wheel is going to fit either 130mm or 135mm dropouts. If your bike has 126mm dropouts there are 2 or 3 ways of working around that. It's not too big of a deal.

2. Look at the back of your 7-speed cassette. It probably has some tiny boltheads or rivets sticking up that hold it together. You need to remove those or file them flat to make the cassette sit flat against the spacer.

dvs cycles
11-18-07, 08:52 AM
Besides the rear drop out spacing being wider, the lockring type is different on 7 sp than on 8/9/10sp.
Would be simpler to just put an 8sp cassette on and just adjust for the hi or lo gear you want to use.
Then look for an 8speed shifter eventually.
Gawain
11-18-07, 10:20 AM
Ok guys, thanks for your answers. I will check the dropouts. It might also be the occasion to go 8 speed. My drive train is a 15 year old deore LX whose retirement is long due.
Jed19
11-19-07, 11:29 PM
Ok guys, thanks for your answers. I will check the dropouts. It might also be the occasion to go 8 speed. My drive train is a 15 year old deore LX whose retirement is long due.

I have a 1994 Cannondale mountain bike that also has a 7-Speed LX drivetrain, and just like you, thought maybe I could pick up cheap 8-Speed shifters/brifters and upgrade to an 8-Speed drivetrain. I had my eyes set on a used pair of Shimano XTR ST-M910 brifters offered on e-bay, which would have been perfect with my cantilever brakes. You can imagine my horror, when a bid that started out at $1, ended up at $76, with an additional $7.90 for shipping!

And I thought initially that I'll pay $10 for them, which plus shipping, equals around $20! Ha!

My advice is to make sure that whatever shifters/brifters you are considering, are indeed compatible with your brakes (Cantilever or Vs).

Can you imagine a circa 1992 used brifters going for $83.90? I decided I'll keep my 7-Speed drivetrain for now. As a matter of fact, 7-Speed looks pretty good right now.

Regards,