chuckybb

I'm correct in assuming that I could fit a 130mm OLN rear hub on an old steel frame that has an existing 126mm hub?

FBinNY 

Yes and no, depending on how finicky you are.

In a pinch you can simply flex the frame far enough to fit the wheel.

The drawback is that the dropouts won't be perfectly parallel. Also less than ideal if you expect remove/replace the rear wheel often, ie. to fit bike into your trunk.

OTOH, if this is a steel frame, you could permanently spread the rear triangle and square the dropouts making it a perfectly fine 130mm bike.

2old

No problem; FME you won't even need to cold set the frame. It could be helpful to install/uninstall it a couple of times in case you need to change a flat some night.

grumpus

You are correct - you may even be able to use it without modification by springing the stays as you insert the wheel, but it's better to set the back end to the correct width, and check dropout alignment, before using the wider hub. I did one the other day with a car jack, the first time I've used that method - I usually use a couple of pieces of 2x4 but the jack was on the floor next to the bench, and the lumber is under a pile of stuff. Quick and easy, got it at the first attempt stretching 135 mm to 141 mm (apparently 141 is an actual size, I just made it fit a hub motor that was supposed to be 135 but is wider).

70sSanO

The problem is the number of speeds. If you stuff a wheel in there, you will most likely flare the dropouts and the hanger won’t be straight. If you are going to run friction shifting, it probably won’t matter.

If you are jumping to 9-10-11 speed index it will probably have issues. Most threads where there are shifting problems will have at least one is the hanger bent response. I can’t imagine not having a hanger issue if you don’t cold set and align the dropouts.

John

andrewclaus

Go ahead and do it. If the wheel won't stay centered when you accelerate, you'll want to align the dropouts. A closed-cam QR skewer might do the trick too.

zacster

I did it 20 years ago to a bike, put a 10sp wheel/cassette in, and used it with friction shifters without problem. It actually shifts much better than the old 6 or7sp it replaced, and is quiet. The ramps on the HG cassette make the shifts really quick with only a slight shift of the downtube lever, and it always lands in gear because there is so little room between them. There is none of the clanging sound. I will be riding that bike next week when I'm in Seattle with my son. He took it with him so I'd have a bike to ride when I'm there, where I originally had it built back in 1981.

Also, 11sp wheels are actually 131 spaced, at least Shimano wheels are. They stole that extra mm to give it more room. An 11sp freehub is 1.8mm wider, so it uses that 1mm and gets a little more from shaving something down a bit. It fits fine in any 130mm frame, but that's just a little more stretch for a 126 frame.

KerryIrons

Agreed. I did this once and after many thousands of miles, the frame had cold set itself and the wheel went in and out without having to spread the frame at all.

dedhed

Depending on the year of frame it may actually be 128mm so that the same frame could use 7 or 8 speed drivetrain depending on the model it would be.
I've found this to be the case on a few frames at the transition years.

Kontact 

Shimano introduced 130mm spaced hubs with the expectation that you would just force them in to a 126mm frame. I doubt there is a single documented frame failure from doing this.

70sSanO

Shimano introduced 130mm hubs to add speeds and sell more components.

Bike mfg’s introduced 128mm dropouts so they could offer 126mm and 130mm drivetrains with the same frame at different price points.

No one cared about 126mm dropout frames, just like no one cared about 120mm dropout frames when 126mm became the standard.

John

chuckybb

I'm correct in assuming that I could fit a 130mm OLN rear hub on an old steel frame that has an existing 126mm hub? Could I just put a smaller left hand axle spacer on to make up the 4mm? Any problems with that?

bboy314

If you just reduce the spacer on the left side, you’ll have 2 potential issues:

1. Unless it’s a bolt-on wheel, the axle will be too long for the frame and will prevent tightening the wheel. You can fix this by cutting down the axle.

2. Your rim will no longer be centered to the hub. You can re-dish the wheel to take care of that but the spoke tension may get dicey.

FBinNY 

I'm fairly sure it's that you simply reversed the proposition, but you cannot add a spacer to the axle to make it narrower.

Assuming you meant you have a 126mm wheel and 130mm frame, yes, you can add a spacer on the left side but you'll have to float a QR axle to center it so there's enough protruding at both ends. You may also need a new skewer if it's QR. Since you're only adding the spacer on one side, you should (but probably don't have to) re-dish the wheel.

OTOH the other way; 130mm wheel into 126mm is find, the frame has enough flex to allow spreading as the wheel goes in. BTW there's another thread that covers this in more detail. Rather than duplicate effort, please search that one out.

KCT1986

Is this question supposed to be different from your prior question? Having the frame professionally adjusted to 130mm would be best. Or doing the hub at some in between OLD (128mm?). and 'springing' the frame during wheel installation.

If this is just about reducing the left side spacers to get to 126mm, then see response #2. The second part of the response is about having to recenter/redish the wheel. This will change the right/left tension balance and may cause some problems with strength (depending on what the tensions are at 130mm).

A better approach, if possible, is to reduce the spacing on both the right and left side. 2mm on each side would be ideal, but 1mm R & 3mm left would at least be better that 4mm on the left.

What model hub are you working with? How many speeds are you running on the back?

Kontact 

That doesn't change the fact that Shimano engineers and lawyers had no concerns about putting 130mm hubs in any 126mm frame and that leading to failure, because there were no 130 or 128mm frames when DA 8 came out.. And it doesn't cause failures.

70sSanO

Well you certainly are digging pretty deep there with Shimano engineers and lawyers with no concerns about 130mm OLD hubs in 126mm frame. Show me one Shimano document referencing an install of a 130mm hub into a 126mm frame. Just one.

As for no 128mm frames when Dura Ace 7402 came out. I think you need to take a trip down memory lane. DA7402 came out in 1989. Mfg’s were already going to 128mm before that. My 1988 Cannondale is 128mm.

You can’t possibly believe Shimano would release a group set that would not fit into a current frame and just shove it in there. Mfg’s knew what was coming. As for mtb, they went to 130mm before road did, so it wasn’t just out of the blue.

John

70sSanO

The truth about 130mm OLD into a 126mm rear dropout frame is sometimes you can shove it in there with no issues, sometimes the dropouts flare. When cold setting a steel frame the same holds true.

When using 2x4’s, threaded rod, bottle jack, or whatever, the frame has to flex beyond how it was produced. There are no absolute guarantees that every frame will flex consistently on the DS and NDS. It is generally a backyard/blacksmith process with no jig but generally works fine.

John

chuckybb

Yes this question is different. I'm investigating options for the 3 Dura-ace 7700 hubs I just acquired. I'd rather not cut axles bend frames.Thanks for your comments.

Kontact 

DA 8 speed came out in 1989, not 1988. Your '88 Cannondale has 128 spacing because the frames commonly warped during heat treating. Here's a 1989 catalog. On page 21 of the PDF it says "Standard 126mm rear dropout spacing" for their racing framesets:
https://vintagecannondale.com/year/1989/1989.pdf

Here's a photo of the 8 speed, 130 spaced 1989 DA rear hub. Note the curiously tapered locknut clearly visible on the NDS side of the rear hub, but both sides look like that. That's Shimano's innovation to spread 126mm frames simply by pushing the hub into the dropouts, because there were no 128 or 130 road frames in 1989. You'll note the front hub locknuts are not tapered, nor are 7 speed locknuts of that same model year.



Yes, Shimano intended this hub to spread frames. No, it didn't seem to hurt any frames that I have EVER heard of. And no, your 1988 racing frame was not supposed to be 128mm spacing. I worked on an a LOT of 1988 and 1989 Cannondales when I started wrenching (including my own 3.0), and the dropouts where never a loose fit for normal 126mm hubs of the time.

Kontact 

Starting in 1990, Cannondale started offering road frames in either 126 or 130 spacing. Page 49:

https://vintagecannondale.com/year/1990/1990.pdf

70sSanO

Nice dissertation. But still waiting for the Shimano Tech Doc that Shimano engineers published for 130mm hubs in 126mm dropouts.

Take your time.

John

Kontact 

Complicated question. I have done this, but there are several factors:

1. The axle itself is too long. So even if you decrease the 'over locknut spacing', the axle is going to stick too far out of the dropouts for the QR to close correctly. So you could cut the axle down to the proper length, or replace it with a different axle.

2. You'll have to redish the wheel because you just moved everything to the left, including the rim. Shimano created 130 specifically to avoid the increased dish on the drive side spokes, 25 years later when 11 speed came out they did exactly that and just moved the right hub flange to the left. I was building up a 1987 Cannondale and didn't want to have to try to spread that ridiculously stiff rear triangle, so I rebuilt an 8 speed Ultegra hub to 126 and redished like the 11 speed Shimano's. You only need to redish half the distance - so 2mm. It came out just fine.

Kontact 

You're wrong, you know you're wrong, and this is what people do when all they have left is pride.

If I come across an HB-7402 manual I'll post it. You do the same. But I was a mechanic when this was happening and spoke to reps at the time. This is just the way it was.

But do feel free to post a 1988 Cannondale spec sheet that shows this 128mm spacing it came with.

grumpus

You'll be moving the rim 2 mm towards the drive side, which will increase the imbalance in spoke tension. You'll have to find somewhere for the extra 2 mm of axle at each end - you might get away with doing nothing or it might foul the QR so you have to remove some axle.