rear wheel spacing debate
 

Ok so i was having a talk with someone about rear wheel spacing. I have a frame that has 126 rear spacing and i've put 130mm wheelsets in it. Should i have this frame cold set to 130 or just leave it the way it is. It's only 4mm difference which is 2mm on each side. I've been using the 130 wheel on the 126 mm drop outs with no issue. sure it's just a little tight when i put it in but other than that i've had no issues.

can anybody provide some advice or info?

I've been doing this for over 20 years and have managed to stay out of jail.

In steel you can do this w/o any problem. Some guys are just anal about it and everything has to be right to the mm with them. But no, there is not a problem if you are doing it.

My dad shoved a 130mm wheel in a Yokota fame in the mid 90s and I am still riding the same framest that way today.

I would be hesitant with aluminum, and wouldn't think about it with carbon, but steel frames shouldnt be an issue.

The only thing I would consider doing after would be double checking the rear derailleur alignment afterwards with the 130 mm wheel in place, especially if using index shifting.

Keep in mind there IS the risk without cold-setting that only one side of your stays move, or one side moves more than the other, changing your chainline, impairing shifting and causing faster wear of the drivetrain components. It's rare, but I've seen it happen.

I find it's best to cold-set just to avoid these issues, but it's obviously not always necessary.

My Miyata spaced at 126mm works just fine with a 130mm wheel even with modern, tightly spaced 9sp indexed gearing. In fact, my tandem bike somehow seems to shift fine with 7sp indexed shifters. I'm pretty sure it's 110mm or something and I've got a 126mm wheel jammed in there. I know this one should be cold set, but it shifts fine and it's a rusted old junker anyway... So yeah, just shove the wheel in there and if it shifts fine, don't worry about it too much unless it looks like it's off to one side for some reason.

The chainstay has to flex way more than 2mm for any cold-setting to occur, and up to that point of yield the flex is completely elastic and thus will be symmetrical between the two chainstays.

The problem with one chainstay going out further than the other chainstay occurs when the two chainstays are forced apart against one another during a deliberate cold-setting operation. In this case, one of the chainstays will almost always reach the yield point before the other, and so the spread-out chainstays would now be centered off of the frame's centerline.

One other concern about simply forcing a wider axle into a frame is that since the left and right chainstays are now pre-loaded to the left and right sides, respectively, any large side-force applied to the wheel will stress the same-side chainstay significantly more than the opposite-side (of the applied force's direction) chainstay, and thus is more likely to exceed the yield strength of the chainstay and thus go out of alignment.
Possibly this what AlbertaBeef experienced after a forced-in wheel was ridden for a while.
Yes, this can happen. Essentially, it is as if your frame's yield strength is reduced.

Small increases in hub width are no big deal though.
I use a custom axle with 124mm locknut spacing to allow a 7-speed rear wheel on my 121.5mm PX10LE's frame, and Shimano even designed special "ramped" (semi-conical) locknuts that allowed their first 8-speed, 130mm Dura-Ace freehub to wedge more easily into the 126mm and 128mm frame spacings of that era.

I obviously don't know any better, but I hear the debate.
I've only done it without coldsetting to about 20 bikes.

Those include an aluminum Cannondale (R700 2.8) and Centurion (Facet) and Schwinn (564), a CF Trek (2500-aluminum rear triangle), a CF Kestrel 200SCi, and 3 CF Centurions (Ironman).

The Schwinn was, by far, the hardest to get the rear wheel into, but it worked.

The steel frames were not too bad, including a 1981 that ran a 5-sp.

None have ever been off-center. None have had any problems.

Ignorance is, thus far, bliss.

This! :)

Brad

+100

I've done it to about a half-dozen steel bikes and it's only been a problem with one of them. After that one I decided to spend the extra 15 minutes to cold-set using Sheldon Brown's 2x4 method and check alignment using the string method. (tie a tight string from dropout to dropout wrapped around head-tube, measure the gap between string and seat-tube on each side to verify alignment)

I've never had a problem after cold-setting and aligning, but then again, I did over 80% of my first few without a problem, so that one bike may have been a "one-off"...

I just placed a 130mm 8-speed wheel on a cinelli frame with 126mm rear spacing. I'm running campy 8-speed down tube indexed shifting with no issues what so ever.

One advantage of cold-setting is that it makes wheel changes a bit easier. Maybe that's outweighed by the option to go back to a smaller axle width. But if you know that you're going to stay at 130mm (or whatever larger width), cold-setting will prevent having to spread the drops with your hands each time you put a wheel on the bike. Maybe this is a minor inconvenience , but it would be almost a must if one plans to race on the bike and expect a quick wheel change.

I'll go with this. :thumb:


Eventually, I will purchase a set of Vuelta Corsa lights for the Trek 460 to keep it as a personal racer for fast 20 and 30milers. I cant see the 4mm giving it any probs. Hopefully I can report the same results as you.

If I were to use a good frame without cold setting, I would at least align my dropouts to be perfect @130mm.

I just stick with 120. Easy for me to say. ;)