Swapping 6sp Uniglide to 7sp Hyperglide
#1
Thread Starter
Chainstay Brake Mafia
Joined: Mar 2011
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From: California
Swapping 6sp Uniglide to 7sp Hyperglide
This seems pretty straight forward.. I just remove the axle and bearings on the freehub side, insert 10mm hex key and unscrew in the normal direction (lefty loosy) to separate the freehub? This can be done with the cogs on the freehub body, correct?
(then redish the wheel of course)
(then redish the wheel of course)
Last edited by frantik; 10-17-12 at 05:02 PM.
#2
Sounds right to me. Just make sure your new freehub body uses the same cone; the 105 used a cone with a rubber seal so the hole in the freehub body was larger to accommodate it. Also the HG body allows for an 11 tooth cog attached to the end. If not re-spaced on the axle, it may not allow the chain to clear the inside of the dropout (just something to keep in mind; it probably will not be an issue).
#3
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Chainstay Brake Mafia
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From: California
I'll be mating a MT60 hub from 1988 to the freehub body from a M454 hub from 1989.. hopefully there will be minimal changes. I have both wheels complete with axles and skewers so i can use parts from the hyperglide hub if i have to
#4
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Chainstay Brake Mafia
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From: California
well i swapped the freehub bodies, that was really incredibly easy actually. I didn't need any parts from the donor wheel besides the freehub body.
To my surprise, when I put the wheel back on with the 7speed freehub body, the wheel was perfectly centered in the frame, and didn't require any redishing...!? I guess the 6sp UG body i have is the same size as the 7sp HG..? it kinda makes sense since there is a some of the threaded UG body exposed.
One potential issue: the smallest cog is running VERY close to the drop out though.. the derailleur can handle it, and everything seems to have clearance, though it's only a few millimeters at some spots.
Do you think the gap between the smallest cog and the drop out will be ok?

This is pretty unexpected, but if I don't have to redish the wheel, I'm not going to bother
If i start noticing the chain making contact with the stay/drop out then i'll mess with the order of the spacers on the axle and redish the wheel. I gotta believe 10 speeds are running with tolerances like this though..
To my surprise, when I put the wheel back on with the 7speed freehub body, the wheel was perfectly centered in the frame, and didn't require any redishing...!? I guess the 6sp UG body i have is the same size as the 7sp HG..? it kinda makes sense since there is a some of the threaded UG body exposed.
One potential issue: the smallest cog is running VERY close to the drop out though.. the derailleur can handle it, and everything seems to have clearance, though it's only a few millimeters at some spots.
Do you think the gap between the smallest cog and the drop out will be ok?

This is pretty unexpected, but if I don't have to redish the wheel, I'm not going to bother
If i start noticing the chain making contact with the stay/drop out then i'll mess with the order of the spacers on the axle and redish the wheel. I gotta believe 10 speeds are running with tolerances like this though..
Last edited by frantik; 10-17-12 at 05:08 AM.
#5
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Joined: Nov 2010
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From: Tixkokob, Yucatán, México
Bikes: 79 Trek 930, 80 Trek 414, 84 Schwinn Letour Luxe (coupled), 92 Schwinn Paramount PDG 5
My bikes run with similar tolerances. As long as there is no contact, no worries. I'm constantly fiddling with different cassettes and freewheels and derailleurs, and have some very close tolerances.
Edit: Great photo! I don't know how you do it.
Edit: Great photo! I don't know how you do it.
#6
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Joined: Aug 2005
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From: Pittsburgh, PA
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
I agree you seem to have adequate clearance between the smallest cog and the dropout face. BTW, 6-speed and 7-speed freewheels and cassettes are nearly the same overall width and use the same 126 mm dropout spacing so it's not surprising you didn't need to redish the wheel.
+1 Very good photo.
+1 Very good photo.
#7
Senior Member
Joined: Jan 2012
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From: Spokane, WA
Bikes: Specialized Sequoia Elite/Motobecane Fantom Cross Team Ti/'85 Trek 520
I was under the impression that the 6 and 7 speed freehubs were the same size so your spacing should have stayed the same like it did.
I agree with the others, if you have nothing hitting the dropouts, you are golden even if its a very close fit. Looks pretty good to me.
I agree with the others, if you have nothing hitting the dropouts, you are golden even if its a very close fit. Looks pretty good to me.
#8
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Joined: Aug 2011
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From: CID
Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)
+1, 6-speed and 7-speed share the same spacing.
Just make sure your derailleur's high limit is adjusted properly and the chain is clean so it doesn't jam in there.
Just make sure your derailleur's high limit is adjusted properly and the chain is clean so it doesn't jam in there.
#9
well i swapped the freehub bodies, that was really incredibly easy actually. I didn't need any parts from the donor wheel besides the freehub body.
To my surprise, when I put the wheel back on with the 7speed freehub body, the wheel was perfectly centered in the frame, and didn't require any redishing...!? I guess the 6sp UG body i have is the same size as the 7sp HG..? it kinda makes sense since there is a some of the threaded UG body exposed.
This is pretty unexpected, but if I don't have to redish the wheel, I'm not going to bother
If i start noticing the chain making contact with the stay/drop out then i'll mess with the order of the spacers on the axle and redish the wheel. I gotta believe 10 speeds are running with tolerances like this though..
To my surprise, when I put the wheel back on with the 7speed freehub body, the wheel was perfectly centered in the frame, and didn't require any redishing...!? I guess the 6sp UG body i have is the same size as the 7sp HG..? it kinda makes sense since there is a some of the threaded UG body exposed.
This is pretty unexpected, but if I don't have to redish the wheel, I'm not going to bother
If i start noticing the chain making contact with the stay/drop out then i'll mess with the order of the spacers on the axle and redish the wheel. I gotta believe 10 speeds are running with tolerances like this though..




