How do I adapt a rear disc brake to an older mountain bike?
 

Basically I have an old Cannondale Delta V 1500 and a Diamond Back Response Sport Pro. I love my old Cannondale but it is pretty much worn out and I want to swap over all the stuff from the Diamond Back onto that frame because it is way too small for me. So far I got a spacer kit to replace the Headshock with my disc brake equipped shocks so the front is covered. The rear is where I have no clue what to do because there are no caliper mounting spots on the frame. Any help would be greatly greatly appreciated because I dont exactly have the money for a new mountain bike.

Thanks
Jason

Easiest thing to do is keep the rim brake in the back. I can't comment on the advisability of welding a brake tab to an aluminum frame.

mtb isn't my forte, but to my knowlwdge there are no clamped on disc brake mounting systems, leaving you no viable options. As I said, this isn't my area, and if you're lucky someone will correct me with a link to some kind of conversion kit.

Otherwise you're SOL, because there's no way to weld bosses onto your aluminum frame, without re-heatreating it making the job more expensive than a replacement frame.

In your shoes, I'd consider going disc front with Canti or V-brake rear. Not too trendy, but you don't need as much stopping power out of a rear brake anyway, and it'll let you keep the frame you like alive without giving up too much.

Sadly, FB's bang on the money.

Still, disc front / rim rear makes a hell of a lot more sense than the inverse. A rear rim is likely to fail before pad wear takes it out, and front brakes are like 85% of the braking equation.

If the V-brake setup is much lighter than a disc deal (I imagine so), then it actually makes quite a bit of sense.

A2Z made one. It doesn't appear on their current website so I assume it's no longer being made, but they're still out there:
http://www.amazon.com/Brake-Mount-Ta.../dp/B003QREO1A

Huh. Well, there you go.

I guess the only caveat is that just perhaps the 'Dale's stays aren't up to it, but I spose that's a slim possibility.

Brake Therapy makes one. I'm debating whether to convert my old Catamount to disc or not.

Consider, instead, Drum Brake Hubs.

Would be interested in how you would go about fitting drum hubs to a bike not designed to take them, and doubt they would work well off road; which the bike is designed for.

If still running Canti's a good upgrade would be to either V type or Magura HS-11 or 33.

Fitting discs is not ideal for that old Alu frame, it has no mounts, the frame wasn't designed for the additional forces the discs puts on it, the costs are significant, new wheels, disc, possibly shifters.

Better to save the money, and get a new bike with all this on in the first place, if left as original the V1500 has some value as a retro bike

Bear in mind that, even if a suitable caliper adapter is available, the conversion would not only require buying a set of disc brakes but two new wheels with the appropiriate disc hubs and perhaps new brake levers or brake/shifter sets to get the proper cable pull. This conversion is likely to be quite expensive. A front-only conversion will not be cheap but a lot less

From the context, it seems the OP has wheels and brakes that he's transferring to the other (non-disc) frame. Looking at the photo of the Brake therapy adapter, it seems that it will fill the bill nicely, with the only real drawback being more work removing the rear wheel.

The adapter is well thought out, and nicely transfers braking torque up to the Canti boss where the frame is designed to take the load. I might mention that the full rather than half load is going to a single stay, doubling the stress, but I doubt the stays were engineered that close anyway.

The OP should see if he can get user reviews of the adapter, and if it's well made and has good reviews he's found a nice solution to his problem

Thanks guys..I think I will just run V brakes on the back..Alot less trouble

Thats what I have on my early MtB, sealed bearing sturmey archer drum brake hubs ,
front and rear .
braking torque windup is transfered with a band around the blade of the fork,
and the chainstay.

trouble free for 20 + years.. .. new ones add a cassette driver option
and a hub dynamo in combinations.

Its the miserable weather bike now , studded tires, then the smoooth modulation
is an asset when the roadway is Ice Covered.

Take it you mean somthing like the X-RDC, can see this working on bikes designed for it, but the Cannondale V1500 was designed for Canti's, and that would require work in frame and cable fitting, also, a rear weighs almost 1kg, that's a lot of additional weight to drag around if MTBing.

Modern alternatives like Magura's or V-brakes do the same job, lighter and are designed for this type of frame.

I looked into this a while ago, and came to the conclusion that it was not a good idea. Any kind of adapter would be ugly, hard to align properly, and prone to moving or vibrating under braking forces. Maybe a talented and well-equipped welder could attach a proper mount, but not me.

:bang: