I've said this before and still believe it. The makers of the sprocket adapters, Pirate, Sportsman and others should explore a clamp on disc brake adapter for this modification.
If they can make an adapter to mount a sprocket why not a similar item to mount a disc brake rotor? Seems simple to me and a marketable part.
It would be cheaper in the long run than a new hub or rim and the cost of having it laced if the builder isn't up to that task.
Just a thought.
Tom
Hi Guys,
I think the idea of a hub adapter to make a non disc brake hub, disc brake capable can be done BUT it may not be the most cost effective / best solution.
Basically, for front wheel application, you would need to have one of the hub adapters to grip the front hub and then a second piece would need to be machined to attach to the hub adapter and then "step down" and provide the mounting holes ( 6 holes) needed to mount a standard rotor (I suppose this step could possibly be bypassed IF a custom rotor could be machined to directly bolt up to the sprocket adapter without the need to first go to a 6 hole adapter.....I hope that was clear? (if not continue below....)
As a side note, I recently had a customer call me and ask me to make a sprocket for his Manic Mechanic in a 34T size (a size that may not normally work with the standard adapter since the BCD of the mounting bolts are a large 3 5/8") AND he wanted some way to add a disc brake to a non-disc brake hub.
I took that as a challenge and ultimately we made the following parts to help make his vision a reality (see pics)...
The first part is the Sombrero Adapter....Basically its role is to bolt to the MM adapter and "step down" and provide the mounting holes for the smaller sprocket (remember, in this case we were doing a rear wheel setup....IF this was for a front wheel application (assuming that somebody would make a hub adapter for a front wheel hub) the Sombrero Adapter would have been drilled to accept the 6 bolt ISO disc brake rotor and the disc rotor would then be directly bolted to it)....this would result in converting a non disc brake front wheel into a disc brake capable front wheel.
The second part of the rear conversion was a custom made sprocket that mounts to the Sombrero adapter AND provides the 6 holes needed for a disc rotor to mount...We made the 6 holes stand off about 1/4" BUT ultimately a large rotor should be bolted to the sprocket so that the caliper can ride above the sprocket and not interfere with things.
The customer in this case ALREADY had the MM hub adapter so his costs were reduced somewhat....If he needed to purchase the MM adapter AND the Sombrero adapter he may have been better off purchasing a new disc brake wheel to start with.
Anyways, it was an interesting project and a made me think of ways to do things that you may not otherwise think of doing.
FWIW - There was also a fella that bought a Top Hat from us that used it to make a disc brake front wheel from a non disc brake front wheel (using the factory rubber mounts, it is possible to clamp the Top Hat to the spokes (like mounting a sprocket) and then he used the 6 holes of the Top Hat to mount the disc brake rotor....did it work? yes, BUT like mounting a sprocket using the factory rubber mounts the disc rotor wobbled...Plus all the braking stresses was on half the spokes...again, just like mounting the sprocket on the rear using the factory rag joint.
Anyways, it was definitely an innovative way of doing things...did it work? yes, but again it wasn't necessarily the best way to do things...probably it would have been better to get a disc brake wheel either new or used if $$ is an issue.
In either event, I love tinkering with things and that for me is the best part of messing with our motorized bikes.
Have fun!
Andrew
PS - even if you convert a non disc brake bike to disc brakes (at least for the front wheel), please research front fork strength before you do so....that's potentially a whole extra can of worms.....
