Bicycle Mechanics - Speading 126mm to 130mm

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.
TonkaWilson
08-26-08, 12:33 PM
Hey,
I am putting a modern rear wheel on a 40 year old Peugeot PX-10 frame (Reynolds 451)
Anyone done this? Should I heat and pre-spread? Maybe chock to up to 132mm to account for springback?
I don't care about the paint, cuz I'll be stripping the frame.
Thanks for any advice.
wilson
cold only but shouldnt really need to spread the frame too much . http://www.sheldonbrown.com/frame-spacing.html
TonkaWilson
08-26-08, 12:48 PM
Thanks for the link, cman.
However, Sheldon says dont' re-space an Aluminum frame, so I may be screwed.
canam73
08-26-08, 12:55 PM
I don't know a lot about PX-10, but are you sure that it is aluminum? Sounds like steel to me.
TonkaWilson
08-26-08, 01:03 PM
You're right.
I just looked up Reynolds 531 on Wiki and it says:
The approximate alloying composition for 531 is 1.5% Mn, 0.25% Mo, 0.35% C, and is similar to the old British BS970 En 16/18 steel. Its mechanical properties and response to heat-treatment are broadly similar to the AISI 4130 standard alloy steel, also used for bicycle frames, amongst other applications. This material was used to form the front subframes on the famous Jaguar E-Type of the 1960s.
Can I just cold crank it?
Bill Kapaun
08-26-08, 01:17 PM
For 4 MM, just spread the frame by hand when inserting the wheel!
It's not worth the effort to cold set it!
Noah Scape
08-26-08, 01:30 PM
A 40 year old PX-10 would have come with 120mm rear spacing. And it is a Reynolds 531 steel frame.
TonkaWilson
08-26-08, 01:38 PM
I just measured with a caliper and it's about 122mm. I had assumed it was 126mm after a quick ruler measure.
Question stands. Can I get a 130 in there?
Grand Bois
08-26-08, 01:48 PM
For 4 MM, just spread the frame by hand when inserting the wheel!
It's not worth the effort to cold set it!
I can cold set a frame in 10 minutes with nothing but a 2X4, a piece of string and a ruler. It's worth the effort to do it right.
Retro Grouch
08-26-08, 04:06 PM
I can cold set a frame in 10 minutes with nothing but a 2X4, a piece of string and a ruler. It's worth the effort to do it right.
Having done a few that's what I think too.
In fact, since I have a straight edge that's long enough to span from the head tube to the dropout, I'm thinking that 10 minutes is conservative. It surely beats futzing around every time that you have to remove and replace the rear wheel.
Grand Bois
08-26-08, 04:26 PM
I recently acquired an aluminum straightedge (sawguide) that probably cuts it down to less than five minutes.
canam73
08-26-08, 04:30 PM
I recently acquired an aluminum straightedge (sawguide) that probably cuts it down to less than five minutes.
Yes, well, I can Uri Geller a frame into exact alignment & spacing faster than a speeding bullit.
Having done a few that's what I think too.
In fact, since I have a straight edge that's long enough to span from the head tube to the dropout, I'm thinking that 10 minutes is conservative. It surely beats futzing around every time that you have to remove and replace the rear wheel.
What exactly do you have to futz around with. You shove the wheel in and go.
Velo Fellow
08-26-08, 05:45 PM
I've simply "thumb set" two 126 spaced steel frames. Simply spread the drop outs with your thumbs and pull on the 130 wheel. Not a purist's solution....but my two bikes have ridden fine for over two years.
Retro Grouch
08-26-08, 06:26 PM
What exactly do you have to futz around with. You shove the wheel in and go.
I've always found trying to force fit a too wide wheel into a frame to be a PITA. So maybe I'm not doing it right?
I find it easier to fix even simple problems once rather than deal with them repeatedly. YMMV.
BCRider
08-26-08, 06:32 PM
For 122 to 130 I'd be inclined to take the time to spread it according to Sheldon's method as well. That's a lot of spring to have to deal with each time. Especially if you're fumbling around in the rain with a flat repair.
reverborama
08-26-08, 10:04 PM
I prefer to cold set the frames, too. I rode a couple that I spread from 126 to 130 and found that it made changing tires a pain and sometimes the hub would shift in the dropouts when under load. Those problems entirely go away after cold setting. Also I noticed that a lot of frames aren't aligned perfectly when you go to set them so you can end up much better off than you started.
I've always found trying to force fit a too wide wheel into a frame to be a PITA. So maybe I'm not doing it right?
I find it easier to fix even simple problems once rather than deal with them repeatedly. YMMV.
Given that I've taken the wheel out of my "too narrow" frame about half a dozen times over the past 5 years, I really don't see it as a big issue. YMMV
sometimes the hub would shift in the dropouts when under load. Those problems entirely go away after cold setting.
Only if you're also realigning the dropouts parallel to the frame centerline, which is a whole different kettle of fish.
ultraman6970
08-27-08, 01:39 PM
still dont know why u want to do a cold setting in that bike, in my oppinion u dont needed, are only 4 mms of difference. I would be worry about an aluminum or carbon bike but with steel? u can just go open the rear end a little while putting the wheel... no big deal. To 132 mms or 135 mms u need to do cold setting, it is too much.
ultraman6970
08-27-08, 07:01 PM
120 to 130... too much... cold setting
BikingGrad80
08-27-08, 09:13 PM
I'd take it to a good bike shop. For $15 they reset one of mine perfectly to 130 and used special Park alignment tools to make sure the dropouts were parallel. Well worth it
Powered by vBulletin® Version 4.1.12 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.