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Old 03-30-03, 07:56 AM   #1
TELFORD
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MTB: 8/9 sp. shifter w/ 7 sp. cassette

Hello,

I have a 7 sp cass. on my MTB and grip shifter
that I need to replace. And I would like to
change to a rapid fire type.
(the brake is linear)

All the shifters I see in the Nashbar catalog
are either 8 sp. (Alivio)
or 9 sp (deore, lx, xt, xtr).

can I use any of these or do I need to
find specifically 7 sp. shifter?

thank you.
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Old 03-30-03, 02:06 PM   #2
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You cannot use a 9 speed shifter with your 7 speed cassette because the amount of cable the shifter moves per shift is less since 9 speed cassettes are more narrowly spaced. An 8 speed shifter has the same amount of cable pull per shift, however, it will have an extra click in it and your gear display will always be one number off. Honestly I would recommend going with a 7 speed shifter for your application. Shimano still produces some nice 7 speed rapidfire shifter sets and they retail for around 30 dollars. Go to your local bike shop and get some.

-Ryan
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Old 03-30-03, 06:31 PM   #3
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Telford - You can use the '8' or '9' speed shifters, and I recommend them over 7-speed Rapidfire because of their better quality, "if" you re-space your 7-speed cassette and use the appropriate chain. Purchase at least XT (XTR if your budget allows). Your local bike shop can ensure the correct spacers, but, as a last resort, you can talk to a better mail order outfit like Cambria and they'll also make sure you get the right stuff (Wheels Manufacturing makes spacers for every combination of shifters/cassettes).

So, you'll need spacers, a chain, and shifters; and though doing this is a bit of work, you will certainly be satisfied with the results. In my 23 years of off-road riding experience, a 7-speed set-up is superior to 8 or 9 speed cassettes for trail riding (Noticeable differences between shifts). Good luck!
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Old 03-30-03, 07:45 PM   #4
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Better yet, have your LBS order 7-speed Rapid Fire Shifters for your bike. The "better" quality is negated by the reliabilty problems trying to keep the 8/9 speed working with your 7speed.
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Old 03-30-03, 11:33 PM   #5
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Shifters should match cassette, ideally. Should have no problem finding them on Ebay.

General discussion at: http://www.sheldonbrown.org/dura-ace.html
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Old 04-13-03, 08:47 PM   #6
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Spacing and shifting for Shimano 7 and 8 speed systems ARE NOT the same. They are close and an 8 speed shifter will kind of work, but the shifting will not be perfect.

I'd get a new 7 speed rapid fire shifter. They're available through your LBS. Even the low end Shimano stuff works so well that they'll be much better than what you had previously.
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Old 04-13-03, 09:39 PM   #7
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WOW Imagine reccomending buying parts from a LBS on Bike Forums. Most mail order probably does nt have 7 speed rapidfire laying around. I can get anywhere from Altus to STX rapidfire all day long starting at $14 to $32. Mayne even less if someone has them on sale or closeout.
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Old 04-14-03, 03:15 AM   #8
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I got a 7 pr casette and 8 speed rocket grip shift, works sweet. 7 and 8 speed shifters are compatible since they have the same spacing (2:1 mm ratio) whereas 9 speeds have a 1:1 mm ratio, so they wont work. Ill have to change casette soon, so it will be a 8 sp now, after all i might as well use the whole range of that grip shift. but if u consider changing shifter, id go for a 9 speed, and change casette too. Keep in mind that cassette wears down rather quickly, so you will have to replace it couple times before u even consider buying new shifters.
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Old 04-14-03, 04:53 AM   #9
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Nik is correct. I ride 7 speed with 8 speed shifters all winter, I use an old 7 speed wheel to run mu studs for commuting. In the summer I switch wheels to a new and better set that has an 8 speed hub. I don't even need to turn the adjustment barrel, they work and shift like swiss watches.
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