How do I add disc brakes to my mountain bike and what's needed?

Question

I own a 2005 Specialized Stumpjumper FSR.

Answer 1

First question: are your wheels disk compatible? Second question: do your bike and fork have disk brake bosses?

If the answer to both questions is: yes, you can put disk brakes on your bike.

The next question is: do you want mechanical or hydraulic disk brakes?

In my humble opinion, mechanical disk brakes have no advantages over rim brakes unless you are constantly riding in wet, muddy conditions. Otherwise, they are heavier and while they may provide stronger braking action, rim brakes do a perfectly adequate job, weigh less and cost nothing extra.

Hydraulic brakes, on the other hand, require only a feather touch to stop. Thus the advantage is you can take super long rides with epic downhill runs and your hands and arms will never cramp up and/or fatigue from constant braking. Hydraulics, of course, are more expensive. Plus, hydraulic systems include levers so you have to take your old levers off and reroute the cables.

Installing disk brakes can be done by yourself. However, some systems (especially Magura) require exceedingly fine tolerances or the brake pads will drag the rotors. Personally, I'd take the bike to your local bike shop and have them do the job. They'll have the tools to face and/or shim the disk brake mounts for perfect operation. Also, some forks (like Manitou) require an adaptor or disk brake specially made for the orientation of the disk brake mount.

Hope this helps.

Answer 2

I had a 2004 Stumpy FSR. The bike is disc ready, meaning you only need to buy the disc brakes. Unless they changed from the 2004 to 2005 models, the hubs are for disc brakes and the frame and fork should have the tabs for adapting them.

You have two options: go mechanical or hydraulic.

Mechanical are cheaper, and you could use the same brake levers than your current ones. If you go mech, go for Avid BB7 ones, they're the best mech out there from what I've heard. Even if the BB5 are cheaper, I wouldn't recommend them. The difference between the BB5 and BB7 that make the -7 worthwhile is that the 7 uses the same brake pads as the juicy series, and I think that would make it easier to buy new pads when the older ones wear out.

Hydros usually are better than mechanicals, in my opinion. Usually they come with the hoses and levers, so you don't need to worry about them (I think all do except Shimano, in which you buy everything appart). I have now some Hayes HFX-9 on one bike and Shimano XT on another bike. The XT have a lot better modulation than the Hayes, and maybe a bit more bite. But I think that Shimano sells the brakes with the centerlock adapters, which would mean a different hub. You could buy separately the 6-bolt rotors, but consider that in your budget.

Avid Juicy 5 I think are a good option, Magura Martha or Louse FR also, Hope Mini, Formula Oro and other ones. It just depends on how much money you're willing to invest in.

Good luck.

Answer 3

According to this site the bike is disc compatible. Perhaps if you cruise around a bit you will find a good article here.

It does sound like some models of this bike come with disc brakes. Perhaps chat it up at a local bike store.