reroll

Velo Orange is selling Dia-Compe 126mm rear dropout-space freewheel hubs having modern sealed bearings, not cup and cone, with left centre-to-flange 41mm and right centre-to-flange 21mm. In other words a 10mm offset to the right would produce a 31/31mm centre-to-flange spacing to then build wheels with zero dish, strong wheels, which could be used by putting the 126mm hub into 138mm rear dropout-space along with a longer axle and necessary spacers. But as the question, can the original 126mm hub axle be removed and replaced by a longer axle, perhaps 12mm longer?

tFUnK

I am having a hard time visualizing being able to change the flange-center distance on a hub.

You can re-space the axle however you want but all that does is move the wheel left or right in the dropout. How does this make the wheel stronger?
Edit: Ok I think I understand what you're trying to do. You're going to dish the wheel to have more balanced tension, and then adjust for this dish by respacing the axle.

Not familiar with the particular hub but every hub I've owned have had removable axles.

Hondo6

In theory, yes. But there's a potential issue that may or may not arise if you try to do a swap.

Some sealed bearing hubs uses axles with shoulders to keep the bearings in place. This eBay listing shows an example:

https://www.ebay.com/itm/392503230866

I'm not familiar with the VO hub in question. But if it uses a shouldered axle, finding one with (a) the shoulder spacing you need, and (b) of the correct length and offset to do what you want might be difficult.

reroll

Thank you, your response to my question gets to the very question I had in mind, that some axles use shoulders to locate the bearings and others do not, and I suppose the only way for me to know about shoulders here would be to take one of these hubs apart and have a look-see.

I am 99% sure these hubs are made by Dia-Compe, a wholesale business which sells only in 100-unit lots, no retail, and Velo Orange has them made by Dia-Compe with VO markings; https://velo-orange.com/collections/...heel-hub-126mm I have old bikes with 126mm dropout spacing and already have two of these beautiful 36h VO hubs. I do not have the equipment to pull one of these hubs apart but there are several bike shops in the area where I am which likely do and can.

Yes, in theory, within 138mm dropouts these 126mm hubs could be located to produce wheels with no dish. Freewheel hubs are very reliable, in the 1980s I put thousands of commuter miles on them and 14-34T freewheels and 48/46-36/34-26/24T 110/74mm triple chainwheels are available today, fine for commuting and touring.

HillRider

Another problem I see with substituting a longer axle is the amount of unsupported overhang it will give on the nds.

reroll

Yup, the same as what happened with 8-speed freewheels, bent and broken axles, which in turn produced freehubs.

I am thinking about solid bolt-on axles, not QR, and made out of hardened tool steel, expensive but strong.

6-speed freewheels work reliably well and are available today in a wide range of useful gearing at low cost.

But yes, front derailleurs would be necessary.

icemilkcoffee 

If it's a threaded axle, then you can easily replace it with a longer axle. If it's a larger diameter smooth axle - these are often times proprietary and you are not going to be able to find a longer version easily.

By the way what bike comes with 138mm drop out spacing, as opposed to the common 135mm (for MTB's)? For 135mm spacing, running a threaded axle freewheel hub is just asking for trouble. There is too much unsupported overhand on the DS. If you are obsessed with solving the dishing problem, the best approach would be to run a narrower 7 speed freehub. You can find early Deore hubs with 7 speed freehubs. Use a longer axle to space these out to 135mm. For further improvement, run an asymmetric (AKA off center) rim.

Dave Mayer

Looking at the pic of the VO hub, they have threaded axles. So the cartridge bearings on both sides are retained by a (likely) 12mm collar that is drilled and threaded to mate with a standard 10mm axle. I'd guess bog-standard 6001 carts. Suntour and many other freewheel hubs used this design.

So it would be simple to replace the old axle with one longer - cut to size of course. You'd also need some spacers to fill out the non-drive side. At my local Co-op, this whole operation would cost less than $5 and take less than 30 minutes, including cutting the axle to size with a hacksaw.

BTW: having a cartridge bearing exposed to the elements is not good design. Cartridge bearings feature simple rubber air dams, which are inadequate to protect against water, particularly water under any pressure. Cart bearing hubs can be adequate if they feature double seals, separated by an air gap, like the old Suntour hubs. But, they are still inferior to cup and cone hubs like Shimano, both in terms of design and execution. And freewheel hubs are inferior to cassette hubs in design and flexibility. I have dozens of high-end freewheel hubs such as Dura-Ace, Superbe Pro, Record, etc. Rode them for 3 decades; rarely any more.

Hondo6

Possible, and perhaps likely - but not guaranteed. Here's an example of a rear hub axle (10mm dia, M10 threaded, 145mm long, for 135mm dropout spacing rear hub) that uses a shouldered axle and sealed bearings. It's definitely threaded at each end.

https://www.modernbike.com/origin8-r...r--m10x135x145

The linked axle kit is for a freehub-type hub, not freewheel. But my point is that without seeing the internals or hearing from someone who has, we don't know what Dia Compe actually did when they made the hub.

I hope you're correct, as that would make the OP's conversion possible and fairly easy.

reroll

Oops! I was thinking 135mm but accidentally keyed 138mm instead.

Here is the 126mm hub I am looking at; https://velo-orange.com/collections/...heel-hub-126mm Looking at the two images available there, threads apparently are on both ends of the axle which got me to thinking the axle could simply slide out once un-nutted. But I do not have X-ray vision to see what goes on inside the hub so here I am to ask about that.

Yeah, you are right about the axle strength, which has known limits. 130mm dropouts got invented to handle 8-speed freewheels but 8-speed freewheels then exceeded the axle strength and freehubs then became the way to go, assuming more than seven hub speeds would be needed.

Offset lacing is somewhat of a gimmick, looking great on paper but producing offset dynamic loading to flex the rim on every revolution of the rim, a bad design. The load should be on the centre of the lacing. Ask any mechanical engineer and they will tell you the same.

Altogether, it looks like a 126mm freewheel hub in 135mm dropout spacing could produce a near-zero dish, but perhaps not with these hubs. There is potential here but a stronger axle would be needed, perhaps a redesign of the hub to work with modern through-axle technology.

shelbyfv

Yes, they have an attractive thru axle hub that will also work with 135QR. VO Hub

icemilkcoffee 

Can you elaborate on this? Why is there a problem with the load not being on-center? You understand that all automotive rims are off centered, right? As are automotive wire wheels, which are analogous to bicycle wire wheels.

Like I said a 7 speed cassette hub would have the same benefit, minus the weakness inherent with the freewheel hub.

reroll

Hehehe! I am with you about cup and cone bearings and in my toolbox I have all of the specialty spanners and tools needed to adjust them. The best feature of cup and cone bearings is that they can be gently preloaded to eliminate any looseness which can not be done with cartridge bearings. I can tolerate cartridge bearings on the rear hub but much less so on the front hub and the same could be said for headset bearings. But cartridge bearings are great for bottom brackets.

Yeah, I was thinking it would be simple to swap-over to a longer axle but here on this thread I have been reminded of axle strength limits as were discovered by 8-speed freewheels on 130mm dropouts. A near-zero dish could be developed but it looks like 12mm thru-axle technology could be necessary.

Freewheels are a reliably good technology, I have put many miles on them and for commuter/tourist use a 6-speed freewheel + triple or double chainwheels running on 8-speed chain could do practically all of what they would need, working well and lasting long.

reroll

The weights of bike + rider + cargo = the load on a bike's wheels and human-powered bikes are designed to be efficient, of minimalist construction. A bike's load gets carried on the centre of its tyres but offset spokes put a cantilevered, torsional load on the rim at the moment it is carrying the load, causing the rim to deflect, but then as the wheel rotates the load becomes removed from that same place on the rim, causing the deflection to return to its original position, so as the wheel rotates there is a continuous cycle of the rim being slightly bent and then becoming straightened, effectively a perpetual cycle of bending and re-bending which can weaken the rim.

I have considered 7-speed freehubs but have you tried to get replacement parts for those 30+ year old hubs? Freewheel hubs are reliably good for 5- and 6-speed and can work well with 7-speed but 7-speed freewheels did not always fit in 126mm dropout spacing.

Steel Charlie

So those bazillions of dished wheels scattered over the planet are engineering disasters on the verge of happening? How worried should people be?

Asking for a friend

shelbyfv

He's just repeating stuff he heard in the 1980s. I think we'll be OK.

Steel Charlie

But how can you be sure? I mean, I've been putting my life at some real risk for decades ! ! How long can my luck carry me thru this? I mean, immanent collapse every time I press on the pedal. OMG !