Axle standards for cross bikes - Today's rant

[fthefox]

I had the bad idea to try a teammate's cross bike with discs. Out of curiosity, went to the LBS to see what modern disc cross bikes they sell. Pretty surprised by the state of things regarding axles: it is all over the place! 135 QR, 142x12 TA, QR, 12 mm or 15mm TAs at the front. Could not they get along and agree on one format?

[oldpotatoe]

I had the bad idea to try a teammate's cross bike with discs. Out of curiosity, went to the LBS to see what modern disc cross bikes they sell. Pretty surprised by the state of things regarding axles: it is all over the place! 135 QR, 142x12 TA, QR, 12 mm or 15mm TAs at the front. Could not they get along and agree on one format?

Nope, not yet. Kinda evolving to 12mm TA front and rear. But no standards for this 'standard', like BBs. For some hubs conversion is possible but for others, nope. Same for frames/forks.

[Mark McM]

Nope, not yet. Kinda evolving to 12mm TA front and rear. But no standards for this 'standard', like BBs. For some hubs conversion is possible but for others, nope. Same for frames/forks.

Although there are many different BB "standards", there are at least some adapters that can be used to match many different crank/frame combos. Are there any wheel/frame/axle adapters that can be used to match otherwise incompatible frames and wheels?

In the case of using wheels and frames with matching axle standards, is there any standards for rotor offset (i.e., lateral location of the brake rotor) to make it possible to interchange different wheels without re-aligning the calipers?

[ColonelJLloyd]

Are there any wheel/frame/axle adapters that can be used to match otherwise incompatible frames and wheels?


There are adapters for 15mm TA front hubs to QR from aftermarket manufacturers. As said, many hub manufacturers utilize a design that allows for various end caps.

In the case of using wheels and frames with matching axle standards, is there any standards for rotor offset (i.e., lateral location of the brake rotor) to make it possible to interchange different wheels without re-aligning the calipers?

I believe all use the same standard, whatever that is. But there are always manufacturing tolerances. In many cases you can shim the rotor on one wheelset to make a seamless switch. But, in reality, this takes only seconds with one allen key when using dual action disc calipers. Not the proper solution as a pit or spare wheelset, but for anything else it's dead simple and fast.

[oldpotatoe]

There are adapters for 15mm TA front hubs to QR from aftermarket manufacturers. As said, many hub manufacturers utilize a design that allows for various end caps.



I believe all use the same standard, whatever that is. But there are always manufacturing tolerances. In many cases you can shim the rotor on one wheelset to make a seamless switch. But, in reality, this takes only seconds with one allen key when using dual action disc calipers. Not the proper solution as a pit or spare wheelset, but for anything else it's dead simple and fast.

I think what he's asking if ya got a 15mm TA fork, only a 15mm TA hub will
Work, same for rear triangles. In 5 years, when they finally go to some standard, that 'mutt' hub may force you into a new frame/fork.

[eBAUMANN]

If you only have one thru-axle bike, whatever, 12mm or 15mm, doesnt matter.

HOWEVER

Considering that 12mm doesnt exist in the MTB world, and people are largely using MTB components for disc CX purposes...its kinda nice to be able to have 3-4 wheelsets that can be used across 2-5 of your bikes instead of having 3-4 sets of 12mm wheels and 2-3 sets of 15mm wheels...this obviously depends on how many bikes you own and how much you like swapping tires or riding tubulars...but you get my point.

Not to mention the used market, 12mm front wheels pretty much dont exist yet, so youll have to adapt whatever you find, if you can.

It really doesnt make any sense to buy a 12mm bike (give the choice) if you also own 15mm bikes...

[sandyrs]

I think what he's asking if ya got a 15mm TA fork, only a 15mm TA hub will
Work, same for rear triangles. In 5 years, when they finally go to some standard, that 'mutt' hub may force you into a new frame/fork.

Realistically very few hubs on the market are specific to one standard. Most manufacturers seem to have enough foresight to give them swappable end caps. Of course that doesn't cover every case (god forbid someone makes a Boost cx bike) but it covers a lot.

[unterhausen]

I have no idea why they went to 12mm front, it seems like a truly pointless difference from 15 mm. Maybe hoping to have it die out is magical thinking, but 20mm is mostly gone except for downhill.

[sparky33]

I have no idea why they went to 12mm front, it seems like a truly pointless difference from 15 mm. Maybe hoping to have it die out is magical thinking, but 20mm is mostly gone except for downhill.

Indeed. I have never once given a thought to the excess of 15mm front TA on my 2 bikes, over a 12mm front. I do think a lot, however, that I can use the same 15x100,142x12 wheels with a recently acquired mtb.

Wheels I've acquired recently came with endcaps for QR and options for other TAs. The ease of endcaps swaps makes axle standards no more than a minor annoyance for the average cyclist.

And perhaps the only thing keeping 12x100 alive is the Enve fork, which now has lots of worthwhile 15x100 competitors.

[sparky33]

Also, the explosion of mtb axle and bb standards makes the handful of cx axle standards look rather quaint.

[eBAUMANN]

And perhaps the only thing keeping 12x100 alive is the Enve fork, which now has lots of worthwhile 15x100 competitors.

This really cannot be overstated.

[ColonelJLloyd]

And perhaps the only thing keeping 12x100 alive is the Enve fork, which now has lots of worthwhile 15x100 competitors.

Should they ever materialize I think Rawland made a bad bet using 12x100 on their Ravn and Ulv.

[oldpotatoe]

This really cannot be overstated.

Except pretty sure bet when the UCI decides to allow disc on road bikes, the rumor is that'll be 12 front and rear...and one rotor size, 140mm(?).

[eBAUMANN]

Except pretty sure bet when the UCI decides to allow disc on road bikes, the rumor is that'll be 12 front and rear...and one rotor size, 140mm(?).

Yes but the build/rim specs on wheels used for road bikes would be different enough (compared to cx/mtb) that it would not be as hard to justify owning 1-2 sets for only that one bike.

[oldpotatoe]

Yes but the build/rim specs on wheels used for road bikes would be different enough (compared to cx/mtb) that it would not be as hard to justify owning 1-2 sets for only that one bike.

I agree but guess I'm saying, Ain't no standard in this disc hub standard, at all.

[Mikej]

So what's the problem? When you get the bike it has what it has. Even if there was a standard you would still have to mail order parts.

[unterhausen]

I guess it depends on how fluid your bike collection is. My current gravel bike has 15mm hubs with adapters to fit a QR fork. Never intended to use that frame as long as I have, but it will be up for sale sooner than the wheels, that's for sure.

[fthefox]

Having bikes that share the same axle/wheels size gives me peace of mine as no bike is ever grounded because of a mechanical. Moreover, there is always a bullet proof "training wheelset" to bring along on race day just in case. That's the reason why the two cross bikes, the road bike and the TT bike in the house still have 10sp drivetrains. Wheels are interchangeable.

Giant bikes are no doubt the best bang for the buck bikes on the market, but there is no way I will own a bike with takes proprietary components, thinking of seatposts and stems here.

So yes, axle types matter to me. I have to say that that I like the 15 TA/142x12 format as I already own mtb wheelsets in this format. Is it overkill for cross? I do not know.