1986 xr250R

I have a 1986 xr250r, I'm interested in converting the rear drum brake wheel assembly to a rear disc brake system. Has anyone done this, and can you tell me what application parts will get the job done. thanks

It will be easier and probably less costly to sell the 86 and buy a newer xr with a rear disk. 

To convert your bike you will need a rear hub , caliper, master cylinder ,line and brake pedal. Then someway to mount the caliper to the swing arm, brake pedal and master cylinder.  It's not going to be cheap or easy. A complete swingarm and rear tire from a newer bike may bolt up but then your still left with mounting up the pedal and master cylinder.

I was going to do something like that on a CR I have. Was going to cost about $400 with used parts off eBay plus the Fab work. 

I'd just run the rear drum. Most of the important stopping force is in the front.

Great bike. Squeeze harder.

Master cylinder mounts on the frame?

Edited by trackmaster

I've converted late XR200Rs, which are based on the 84-85 XR250R chassis. As noted previously you will need to weld a bracket onto the frame for the master cylinder. The rear drum brake is good if it is kept clean and has good linings. When I competed in PNW Enduros, most of which were run in the winter, I needed to clean the drums and brake shoes after every event. Also needed cross cut grooves in the linings to pull water away from the brakes.

What you need for the conversion are parts from a  90-95 XR250R:
swing arm complete w/ axle,
rear wheel,
rear brake assembly
And buy a 90-95 XR250R bake pedal pivot because it includes the arm for the master cylinder.

It all bolts on.

Honda did make a change somewhere in there to the chain slider so I suggest a SA with chain slider and chain guide.  Linkage fits.

Do not use 96-04 SA, it doesn't fit linkage.

Some have used XR600 SA so that is a possible.

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