Upgrading from 7 to 9 speed
04-08-10 | 02:31 PM
#1
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Upgrading from 7 to 9 speed
I'm looking into upgrading the shifters on my bike however since the bike is 7 speed only the sora shifters are available. This leads me to wanting to upgrade the shifters, cassette and rear derailleur to 9 speed. However this is where I run into a problem, I'm getting somewhat mixed information that I can't figure out. Basing this off of sheldon brown's website it says that 7 speed hubs won't accept 8,9,10 speed cassettes however that it will accept 8 cogs of a 9 speed hub.
This leads me to believe that it's not so much an incompatibility of the cassette with the hub so much as the frame spacing on typical 7 speeds(126mm?) however my frame is spaced to approximately 134mm(so I guess it's meant to be 135mm) so it's wide enough to accommodate 9 speed. I would like to avoid adding the cost of a new wheel to the upgrade if possible, so would a 9 speed cassette be able to be installed on a 7 speed hub or no?
This leads me to believe that it's not so much an incompatibility of the cassette with the hub so much as the frame spacing on typical 7 speeds(126mm?) however my frame is spaced to approximately 134mm(so I guess it's meant to be 135mm) so it's wide enough to accommodate 9 speed. I would like to avoid adding the cost of a new wheel to the upgrade if possible, so would a 9 speed cassette be able to be installed on a 7 speed hub or no?
04-08-10 | 02:50 PM
#2
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There is a difference in body length between 7-speed and 8/9/10-speed, so a 7-speed body can't take a full 9-speed cassette. 8 out of 9 however will fit just fine.
If you can get one, you can bolt a 9-speed body straight on to your 7-speed hub(assuming it's a freehub). Seals won't quite line up, so you're better off pulling the whole axle from a 8/9-speed hub and use that.
Your RD will work just fine with a 9-speed setup.
If you can get one, you can bolt a 9-speed body straight on to your 7-speed hub(assuming it's a freehub). Seals won't quite line up, so you're better off pulling the whole axle from a 8/9-speed hub and use that.
Your RD will work just fine with a 9-speed setup.
04-08-10 | 03:39 PM
#3
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From: Oklahoma
Bikes: Trek 5500, Colnago C-50
Is this a road bike or a mountain bike? A standard road bike axle spacing should be no more than 130 mm.
It is possible to replace some 7 speed freehubs with an 8 - 9-speed freehub. From the serial number the hub manufacturer should be able to tell you if your freehub can be upgraded. If your freehub cannot be replaced the rear wheel can be rebuilt with a 9-speed hub or the complete wheel can be replaced.
It is possible to replace some 7 speed freehubs with an 8 - 9-speed freehub. From the serial number the hub manufacturer should be able to tell you if your freehub can be upgraded. If your freehub cannot be replaced the rear wheel can be rebuilt with a 9-speed hub or the complete wheel can be replaced.
04-08-10 | 05:05 PM
#4
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It is a road bike, my tape measure could be off though i'm not sure why it's spaced like that really, thanks for the help, I think i'll use the 8 of 9 setup for now and just get a new wheel when i can. I'm not really all that worried about the gearing anyways, I'm happy at 7 if it weren't for the fact that sora is the only option.
