7 OR 8 speed on same wheel?
#1
Thread Starter
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Joined: Jul 2009
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From: Boston Burbs
Bikes: 1978(ish) Peugeot PRN10e, Specialized Tricross
7 OR 8 speed on same wheel?
Assuming that I have two sets of 7-speed shifters and one wheel with an eight speed cassette, can I swap the 8 for a 7 or is the spindle too large for that? Or should I just run the 7 smallest gears until I can fins a set of 8 speed shifters?
(purple Cannondale M-500. I'm not sure of the year but all but one year of M-500 have 7 speeds and the sifter only clicks 6 times so I am am guessing that I do NOT have a '98)
(purple Cannondale M-500. I'm not sure of the year but all but one year of M-500 have 7 speeds and the sifter only clicks 6 times so I am am guessing that I do NOT have a '98)
__________________
2023 Salsa Journeyer
2023 Rad Rover 6
1980ish Raleigh Marathon (Vintage Steel)
2006 Trek 820 (Captain Amazing) RIP
2010 Specialized Tricross (Back in Black)
2008 Specialized Roubaix RIP
"I'm built like a marine mammal. I love the cold! "-Cosmoline
"MTBing is cheap compared to any motorsport I've done. It's very expensive compared to jogging."-ColinL
Rides:2023 Salsa Journeyer
2023 Rad Rover 6
1980ish Raleigh Marathon (Vintage Steel)
2006 Trek 820 (Captain Amazing) RIP
2010 Specialized Tricross (Back in Black)
2008 Specialized Roubaix RIP
#2
You need a 4.5 mm spacer to run a 7sp cassette on an 8sp hub.
https://www.jensonusa.com/store/produ...te+Spacer.aspx
https://www.jensonusa.com/store/produ...te+Spacer.aspx
#3
If your C'dale has 7 speed shifters, it probably will have 126mm rear drop-out spacing. You'll need to be pushing the chain stays apart to fit the 8 speed wheel in, which will have 130mm OLD.
#4
Thread Starter
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Joined: Jul 2009
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From: Boston Burbs
Bikes: 1978(ish) Peugeot PRN10e, Specialized Tricross
Hum. The eight-speed hub sipped right in there!
__________________
2023 Salsa Journeyer
2023 Rad Rover 6
1980ish Raleigh Marathon (Vintage Steel)
2006 Trek 820 (Captain Amazing) RIP
2010 Specialized Tricross (Back in Black)
2008 Specialized Roubaix RIP
"I'm built like a marine mammal. I love the cold! "-Cosmoline
"MTBing is cheap compared to any motorsport I've done. It's very expensive compared to jogging."-ColinL
Rides:2023 Salsa Journeyer
2023 Rad Rover 6
1980ish Raleigh Marathon (Vintage Steel)
2006 Trek 820 (Captain Amazing) RIP
2010 Specialized Tricross (Back in Black)
2008 Specialized Roubaix RIP
#5
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Joined: Feb 2005
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From: Oklahoma
Bikes: Trek 5500, Colnago C-50
Yeah, many of the later 7-speed frames were 128 or even 130 mm dropout spacing. But you'll need new shifters and new chain and if you need to buy those you could just as easily go 9 or 10-speed. I wouldn't buy 8-speed shifters, 8-speed components are becoming too rare. 9 or 10-speed Shimano cassettes will fit the same hub as 8-speed Shimano.
Al
Al
#6
Thread Starter
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Joined: Jul 2009
Posts: 1,014
Likes: 50
From: Boston Burbs
Bikes: 1978(ish) Peugeot PRN10e, Specialized Tricross
I think that I'm going to be picking up a Kona Blast for off-road and then I'll strip the Trek that I have been building and have plenty of parts for the 'Dale. That thing is, perhaps, the LARGEST MTB that I have ever seen! I intend to put slicks and baskets on it and use it for an errand bike.
__________________
2023 Salsa Journeyer
2023 Rad Rover 6
1980ish Raleigh Marathon (Vintage Steel)
2006 Trek 820 (Captain Amazing) RIP
2010 Specialized Tricross (Back in Black)
2008 Specialized Roubaix RIP
"I'm built like a marine mammal. I love the cold! "-Cosmoline
"MTBing is cheap compared to any motorsport I've done. It's very expensive compared to jogging."-ColinL
Rides:2023 Salsa Journeyer
2023 Rad Rover 6
1980ish Raleigh Marathon (Vintage Steel)
2006 Trek 820 (Captain Amazing) RIP
2010 Specialized Tricross (Back in Black)
2008 Specialized Roubaix RIP






