https://arstechnica.com/...e-for-electric-cars/

Hmmm...do you mean attaching the braking surface to the rim instead of the hub has technical advantages for lightweight, low power vehicles (look beyond the rotor rust reasoning, of course)?

Who'd a thunk?? 😆

https://arstechnica.com/...e-for-electric-cars/

Hmmm...do you mean attaching the braking surface to the rim instead of the hub has technical advantages for lightweight, low power vehicles (look beyond the rotor rust reasoning, of course)?

Who'd a thunk?? 😆

I think I know what you're trying to do, but it's a stretch. In this case the braking surface still has a single purpose, and has no job in retaining the tire. The rotor diameter is still much less than the rim diameter. The rotor is still a consumable that gets replaced over and over on the same rim. The tire and rim do not heat up (much) due to braking. There's a still a disc caliper that's largely the same as existing disc brake calipers, just mounted in a different orientation.

This is just playing around in the design space of a disc brake wheel. It takes some imagination to interpret as a movement toward rim braking.

I give you 3/10 on the troll-o-meter. Nice attempt. Doesn't hold up well to scrutiny.

Though going back to purely cars, this thing looks like it could make changing a flat tire a bitch. Unless there's some quick release mechanism to release the caliper and spares come with the rotor pre-installed.

I think I know what you're trying to do, but it's a stretch. In this case the braking surface still has a single purpose, and has no job in retaining the tire. The rotor diameter is still much less than the rim diameter. The rotor is still a consumable that gets replaced over and over on the same rim. The tire and rim do not heat up (much) due to braking. There's a still a disc caliper that's largely the same as existing disc brake calipers, just mounted in a different orientation.

This is just playing around in the design space of a disc brake wheel. It takes some imagination to interpret as a movement toward rim braking.

https://arstechnica.com/...e-for-electric-cars/

Hmmm...do you mean attaching the braking surface to the rim instead of the hub has technical advantages for lightweight, low power vehicles (look beyond the rotor rust reasoning, of course)?

Who'd a thunk?? 😆

Why? The braking force goes directly to the rim, without going through the hubs and spokes.

correct me if i'm wrong, but the only fundamental difference i see is that the rotor is now mounted to the wheel. which is what we do in cycling. great minds thunk alike ;-)

It ain't even novel. Buell has used this on their front disc wheels since forever.

Changing a flat is just 5 bolts around the edge.
No harder than normal.

That's a little harder, because it's roughly doubling the number of bolts you'd have to deal with.

But I was thinking of the caliper. You'd have to disengage the caliper with the *wheel still on*. Do you pull the caliper through the spokes before you take the wheel off to keep it clear of the rotor? And, of course, the opposite when putting the new wheel on. Then when you re-engage the caliper you'd damn well better hope those pistons didn't extend or else you're in a world of shit trying to jam on calipers while working through wheel spokes. I don't want to be doing that on the side of a freeway.

There'd almost have to some kind of caliper quick-release and hinged joint to rotate the caliper out of the way in-place so you don't have to take it out through the spokes. In the Continental picture there's no obvious room for that, though. It's not an issue with the Buell because you get full access.

And brake bleeding seems like it would involve a lot of profanity.

So I don't see this idea going to race cars where seconds count on wheel changes.

Don't see it going to cheaper appliance cars where ease of maintenance would seemingly take precedence.

That leaves like high performance touring cars, sort of like the notional Ferrrari in the OP?

Do you have a Google Alert set up for "Disc Brake"?

I think you need to look at the exploded view a bit closer. It appears that after removing the 5 bolts, the outer rim and tire come off of the "carrier star" and the rest all stays in place until the new tire/rim is installed. Easy-peasy.

edit: BTW, who said anything about this going onto race cars??

OK, I could see that.



Historically, that's where new car technology - particularly new brake technology - shows up.

OK, I could see that. Thanks.



Historically, that's often where new car technology shows up first. E.g. ABS.

Given that this isn't a new idea and (to my knowledge) it's not being used on race cars, might indicate that the purported advantages are pretty marginal.


But here's some porn for you. Be sure to wipe your work area down with warm soapy water after:

WTH is that? It just looks like a silly styling exercise...

It ain't even novel. Buell has used this on their front disc wheels since forever.

Correction...the key point is the rotor is mounted to the RIM, and not the HUB...hence, the spoked area of the wheel isn't required to transmit braking torque to the tire, with the result being an overall lighter, less mass construction. Also, with the significantly larger diameter braking surface, a smaller, more compact, and more rigid caliper is possible to get the same performance...with an ALUMINUM braking surface, no less :-/

In other words, it's the OPPOSITE of what is being currently pushed onto road bikes....

Now then, if only the use case allowed for narrow enough tires that they could integrate the braking surface into the rim itself and reach the caliper around the tire, huh? That could allow an even greater improvement...

Correction...the key point is the rotor is mounted to the RIM, and not the HUB...hence, the spoked area of the wheel isn't required to transmit braking torque to the tire, with the result being an overall lighter, less mass construction. Also, with the significantly larger diameter braking surface, a smaller, more compact, and more rigid caliper is possible to get the same performance...with an ALUMINUM braking surface, no less :-/

In other words, it's the OPPOSITE of what is being currently pushed onto road bikes....

Now then, if only the use case allowed for narrow enough tires that they could integrate the braking surface into the rim itself and reach the caliper around the tire, huh? That could allow an even greater improvement...

This is how I roll.

i don't think your correction is a correction. it's an observation separate and distinct from my point (which is entirely correct - unless i'm incorrect!).

the problem - one problem - with mounting the rotor to the rim (in a bike) is the rotor is subject to the trueness of the rim which, in practice, turns out not to be (or stay) particularly true. also it requires that the rim have all the qualities of a rotor (it requires that it BE a rotor).

In any case, to paraphrase BryanD, I have high confidence the engineers working on this will be able to overcome ALL of your reservations :-P