specialmonkey

I bought a set of Ofmega Super Competizione hubs on eBay (same green box), but realize the rear is 120 OLD. I've read on bikeforums it's not advisable to make these work in a 126 spaced frame ... I don't have any 120 spaced frames on the N+1 horizon

Would anyone advise making these work in a 126 frame (it is after all only a 3mm squeeze-in on each side)?

If I were able to find a compatible wider axle, would the skewer still be wide enough?

Can anyone recommend a source for 126 axles that will work?


I read somewhere else Ofmega cones and races are more fragile than others, any truth to this?

I believe these are from the early 80s but they almost look to have cartridge bearings. Seals can sometimes look like a cartridge bearing. I haven't taken them apart. Does anyone know? Velobase says they have bearings.

What is the clip in the center of the hub for? Is there a port for oil underneath?

Thanks!

bikemig 

Those do look like they're sealed but it's a little odd that there is an oil port. Perhaps it is for injecting grease? Suntour/WTB had hubs like that and they are very good.

It should be no problem setting up these hubs for a 126 mm frame. Wheels manufacturing has what you want (both axles and spacers).

crank_addict

All you need is a longer threaded axle (matched threads) and appropriate spacers. Use the same cones, bearings, nuts, etc.. Threaded axle does not have to be the same brand.

crank_addict

The oil port and cover clip is old school - squirt and go. The track guys would want the least viscosity by using oil concoctions, they could get away with the oil being in a clean environment and out of the rain.

Those hubs look like they have cartridge inserts but perhaps are lip seals.

specialmonkey

Interesting, I'm guessing they're probably sealed bearings even if they look and feel like cartridge, they're really smooth.

I see I could get this:
https://wheelsmfg.com/products/hub-p...s/axle-01.html with Threads: 10mmx1

but would these threads work on the existing cones, spacers, nuts, etc.? I think the Ofmega axle might have Italian threads on the axle ... (looks like similar hubs)

If not, would other cones, spacers, and nuts work on the above axle, and with these hubs? I'm not sure if the axle os something other than 10mm diameter (like 9.5mm or 3/8).

I may just try an entirely new axle/cone/spacer assembly, and hope it works, but am leaning against ... would rather find correct axle and use existing cones, etc.

Do you think the existing skewer will be wide enough? I guess I just need to see if it's wider than 137mm.

Seller emailed me and said he didn't see any cones, so maybe they are cartridge ... doesn't really explain the oil port.

crank_addict

Regardless of bearing type, you could swap for a longer axle. Possibly the factory oil port was because the shell was used for both cup/ cone ball bearing or cartridge insert type. Are there any numbers on the seal, perhaps bearing I.D.?

Edit. Zooming in, I can partially see numbers and the outer looks thick as if being a cartridge bearing.

3speedslow

specialmonkey

I might just do that, I spoke to the seller who mentioned trying to take them apart, and seeing no cones ... he was concerned it might not be an easy thing to swap in a longer axle ... he said the axle seemed press fit into the cartridge bearing, and he needed to tap it out. I can't tell how it works, and wonder if the axle is missing threads under where it contacts the bearing, or if it's the cone like silver thing on the axle (after the lock nut) that rests under the cartridge, and which is press fit.

There are markings on the (what I think are) cartridge bearings:

front:
w 246
w 227

rear:
f 227
f 100

Bianchigirll 

Take pics and post them.

crank_addict

Is there a makers mark of bearing brand? Maybe try a random cross reference. Typically a 6xxx number with modified prefix or suffix gets one in the ballpark.

With your description of these hubs being smooth, sort of would be nice to just leave as is. I've learned the cartridge bearing is less forgiving vs. cone and bb. You have to get the alignment near perfect on assembly or risk damage in short time.

Serviced these Viscount hubs but funny enough, one bearing on the front hub nearly fell out on removal. On reassembly, I put a drop of Loctite bearing set on the outer. In this hub set, front and rear bearings are indeed different sized. Cross ref the numbers and found all super reasonable prices on Amazon.

crank_addict

Second thoughts.
Zoom appears to show its just an outer shield / seal. Not a cartridge bearing. The inside rubber rides that cone or perhaps spacer. I would go ahead and dismantle, sort out what axle and spacer is needed to attain desired width.

Salamandrine 

Late 70s to very early 80s. These hubs are the same as the Avocet Mod II hubs, which are somewhat more common stateside.

No, you don't want to squeeze them into a 126mm spaced frame.

Ofmega cone quality was just fine. Maybe not campy record quality, but they would hold up and spun smoothly. Roughly the same as dura ace quality of that era. At any rate these use cartridge bearings so it's irrelevant. The oil clip is just traditional, and makes pretty much zero sense for these hubs. Think of it like a fake hood scoop.

Some early sealed hubs used proprietary press fit axles. I can't remember what these had going on inside. I suggest taking them apart. In fact, you'll need to to see what's inside. If they use standard 10x1 threaded axles, you can simply buy a longer one from Wheels mfg, and add a 6mm spacer to the drive side only. If they use oddball proprietary axles, you'll never find replacements, and best bet is to trade them to someone that can use a 5 speed hub.

SurferRosa

I have some of these, and they're cartridge bearing. You can't* simply use a normal replacement axle like the WM 08. I wouldn't know off hand how to switch out the axle. The only other cartridge bearing hubs I had (Specialized) in which I needed a new axle, I bought a replacement Specialized hub and used that axle.

I bought my ofmega hubs nos on ebay and simply pushed a bit of new grease in the bearings before they hit the road.

They're great hubs. The skewers are really nice, too.

* Edit: Maybe I should have written, "you may not be able to" instead of "can't."

Also, mine do not have the oil clips.

Salamandrine 

Maybe, but maybe not. It's true that the Specialized/Sanshin sealed cartridge bearing hubs used a proprietary axle with machined shoulders, but some other early sealed hubs used standard axles. Instead of cones there were sleeve like things that pressed into the bearings. Imagine a cone that's been machined down into something that looks like a coupler. It could be either. I don't remember replacement axles for these, but it's been decades. (there was/is a third type that was a conventional loose bearing hub with seals fitted to it - these are not that)

Regardless, I doubt they're that hard to take apart. I'd start with cone wrenches to get the locknuts and spacers off. By then you should be able to see what's going on.

SurferRosa

Yep, that's what my ofmega hubs have.

deux jambes

Chombi1 

I have low flange Ofmega hubs with the same skewers on one of my wheelsets that I built back in the mid 80's and it has sealed bearings. IIRC, they are the CX model hubs.

Chombi1 

Tip on how to remove the metal dust shields on the hubs without mangling them.
I use the handle end of an old disposable electric toothbrush (which I also use to brush down parts I am cleaning). They usually have a soft (rubberized) smooth pointed end that you can use to lever the dust caps off....
.....gradually with it kinking or bending the soft sheet metal of the dust shields. Screwdriver tips just beat and tweak them up too much because of the sharp edges on them and the hard steel they are made of.

deux jambes

verktyg 

An ounce of knowledge is worth a pound of guesses.... ** see below

Quite a bit of the info on velobase.com is anecdotal. Some of it is very accurate, while some descriptions are based on guesses or opinions....

The top Ofmega/Avocet hubs like the OP's indeed had sealed cartridge bearings.

Most sealed bearing hubs had axles with inboard flanges that acted as stops for the cartridge bearings.The OP would probably have to find an Ofmega/Avocet axle designed for 126mm OLN hubs.

Also most hubs with cartridge bearings need to have some play so they need to be adjusted slightly loose. Sutherland's has a good description of this.

** Ofmega/Avocet hubs used the same threads as Campagnolo: 9.5mm x 26 TPI Front and 10mm x 26 TPI Rear.

Last summer I overhauled a set of Avocet cup and cone hubs. Several of the cones were badly pitted. They had the same dimensions as Campy Record cones and that's what I replaced them with.

@Chombi1 please note: Unlike Campy dust shields the Ofmega/Avocet ones were very soft and easily bent just as in the photos above. I had to use some jeweler's pliers to straighten them.


This shows the angle difference in the dropouts between 120mm and 126mnm. Notice the angles are enough to affect the pressure on the cones and cups in the hub bearings. Going from 126mm to 120mm has the opposite effect.



verktyg

specialmonkey

More on the 120 hubs I want to expand to 126, it's looking more like a fool's errand. The bearings are indeed cartridge. As suggested by crank addict, the oil port is likely for when the hubs are configured as sealed / loose bearing) ... It was difficult to remove the lock and spacer nuts (I think there was a thread locking substance holding them in place, or just old) but they did come off, the axle needed a bit of a tap to fall out, it does seem like an odd ball. Doubtful I could find one in 126. Looks like the threads are 10x26 whatever that means, from printing on the locknuts and spacers, the axle itself is 130mm wide with 3 outside diameters: on and in the threads approx 9.5mm, under where the cartridge bearing would be, raises to 10mm, and the long part in hub body 9.75mm. I wonder If I could use narrower spacers to make this close to a 126? Otherwise it might be more a matter of converting it to sealed / loose type bearings, and using new axle, nuts, cones, and spacers, which seems counterproductive / wrong / not worth it, etc.



Definitely cartridge.


Raised to 10mm beneath cartridge bearing. Lock and space nuts say Ofmega 10x26.

bikemig 

Oh man, I like this. I mangled the dust cups on the last hub I overhauled and I was not happy. Now I just need to find the right kind of toothbrush!

SurferRosa

Isn't the question simply this: can you use a regular axle like the WM 08 so that, unlike the original axle, some axle threads lie under the cone?

We know this isn't a problem with loose bearings. I guess I don't see a problem here either.

Salamandrine 

OK, now you know and so do we. Not nearly as proprietary as the Specialized axles, but still not a standard axle. They simply made a normal axle but didn't thread the ends as far. Even so, I doubt you'll find a replacement in a longer size. You could have a machine shop make one, but unless you have some sort of connection that's not going to be worth it. I'd recommend you trade them to somebody with a 70s ten speed. No doubt someone out there wants a vintage look hub without vintage maintenance, especially if they ride in the rain. Or modify your n+1 plans to include 120...

You could probably space it out a bit with the existing axle, like maybe to 124, and still have enough axle end for reasonable engagement into the dropouts. It'd be kind of a hack though, and I DON'T recommend this.

At any rate, thanks for sharing. It will be helpful in case anyone else runs into this.

specialmonkey

When you say cone do you mean the metal inner circle of the cartridge bearing? With a threaded axle there, it may not be tight enough engagement (in the cartridge bearing) and the threads would almost certainly fold in on themselves.

If I could find spacers nominally 3mm narrower than the current ones (for each side) would that not give me a 126? I'm unsure about how this would affect the freewheel placement / dish, but think it should be OK still? Were 70s 10 speeds spaced for 120? I'd like a 70s Fuji (The Finest or Newest ).