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correct width hub to order??

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correct width hub to order??

Old 10-20-13, 03:45 PM
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correct width hub to order??

Needing new wheels soon for my dad's old bike rebuild.I measured 4 7/8" between the rear dropouts that converts to 123.6 mm and 4" between the fork dropouts converts to 101.6 mm. (It's a 5 speed freewheel on the rear).

So do I need 100 mm front and 120 mm rear?

Thanks,
KF
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Old 10-20-13, 04:09 PM
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You could get away with either a 120mm or a 126mm rear hub, but I'd go for the 126mm for versatility's sake. That way you'd easily be able to mount a 6-speed cluster if the fancy took you.
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Old 10-20-13, 04:21 PM
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+1, I'd also go 126mm, which leaves you the option of going to 6s.

However, most 126 hubs are set up for 6s, and changing them to 5s would involve transferring some spacers on the axle (if possible) and re-dishing the wheel. A 5s wheel on a 126mm axle is a nice thing because it's almost symmetrical, but it'll involve some extra work at your end.
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Old 10-20-13, 04:33 PM
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Sounds great guy's! Thanks for the quick reply.Nice knowing i have options will probably stay with 5 speed but ya never know.

Regards,
KF
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Old 10-20-13, 04:54 PM
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Originally Posted by FBinNY View Post
+1, I'd also go 126mm, which leaves you the option of going to 6s.

However, most 126 hubs are set up for 6s, and changing them to 5s would involve transferring some spacers on the axle (if possible) and re-dishing the wheel.
FB,

Am I missing something in assuming that one could fit a 5spd FW onto a 126 spaced hub (which would be properly dished for that axle spacing) and just set the high gear limit screw in to prevent shifting beyond the 5psd top cog? Never tried, 6spd was the whole point of 126 back in the day.

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Old 10-20-13, 07:18 PM
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Originally Posted by Bandera View Post
Am I missing something in assuming that one could fit a 5spd FW onto a 126 spaced hub (which would be properly dished for that axle spacing) and just set the high gear limit screw in to prevent shifting beyond the 5psd top cog?
Yes, you could just use the limit screws that way, but you'd lose the better bracing you'd have if you dished it for 5-speed. If/when you decide to use a 6-speed block, you'd just move the spacers and re-dish the wheel.
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Old 10-20-13, 08:08 PM
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Originally Posted by JohnDThompson View Post
If/when you decide to use a 6-speed block, you'd just move the spacers and re-dish the wheel.
Occam's Razor. Stick a 6 speed of the appropriate flavor on a 126 and proceed.
Preserving 5spd on a family machine for sentimental reasons fades with the 1st big hill.

Good on the OP for keeping that machine on the road, it was his father's.

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Old 10-20-13, 08:57 PM
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I think the OP needs to think about his plan. If he's planning to stay 5s in the foreseeable future he should either buy a 5s hub, or respace the 6s to reduce dish. However, if he plans to move to 6s next time he buys a freewheel (an easy upgrade with friction shifting), then he should leave the hub spaced for 6s.

Spacing and dishing a wheel to change form 5s to 6s (or whatever) takes roughly 1/2 an hour for an experienced mechanic, but the OP doesn't seem to fit that bill, so changing then changing back would likely be a wasteful expense.
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