1988 xr250 rear drum to disc conversion

[rideredfred]

Is doing this conversion worthwhile I love the bike and plan to keep it as long as I'm able to ride

[Chuck.]

I did a disc/\ brake conversion, the easy way is to use 90-95 XR250 swing arm, wheel, and caliper (w/ bracket). Also need the mastercylinder, hose, and reservoir.  And lastly #20 in the pic to replace your brake pedal pivot, about $30 from Honda. Use Honda brake pads.

You will need to fab a frame bracket for the MC, or Dremel remove one from a 90-95 XR250,  I adapted one from a RM125.

 

Edited September 3, 2013 by chuck4788

[rideredfred]

Thanks for the info I can get all the part I need except the mounting brackets from an 03 xr250 wonder if swing arm will fit

[Chuck.]

The 96-04 XR250 was aredesign from the 86-95 bike.  The swing arm will fit but it is shorter, the link attachment is in a different place,  the linkage is different, and the shock is shorter; I don't know what the rear geometry would be using those parts. But the wheel, caliper, MC, hose, etc will all work.  Check part fiche numbers on the two bikes; the chain guide, slider, and axle assy may also be usable.

 

On my XR200 mods I opted to use 84-95 XR250 parts because all of the SA lengths and linkage attach points provided the same ratio between the 86+ 200 bikes and the 84-95 XR250 bikes (shock is longer on the XR250 but the frame mount is also higher).  I did try fitting a 03 XR250 swing arm and decided it wouldn't work on my chassis.

 

Some chassis history: The new full cradle 84 chassis became the 86-02 XR200 chassis with different motor mounts for the 2 valve motor, the 86 XR250 got an updated chassis with a lot of carry over dimensions and parts from the 84 chassis, then a complete redesign in 96 for the chassis and a dry sump engine.

[Redpoint]

Is doing this conversion worthwhile

That's a definitely a subjective question.  I converted my '87 just to see if I could do it.  Cost me about $250 in parts, rides the same, brakes the same.

 

Would I do it again?  Absolutely not.  Rather sell the older bike and spend the money on a 96+ model.  Far more aftermarket support (+ used and OEM parts for that matter), better forks, factory rear disc, and more.  If you plan on keeping the bike a long time, why start with something that is difficult to find reasonably priced parts for?

[Chuck.]

That's a definitely a subjective question.  I converted my '87 just to see if I could do it.  Cost me about $250 in parts, rides the same, brakes the same.

 

Would I do it again?  Absolutely not.  Rather sell the older bike and spend the money on a 96+ model.  Far more aftermarket support (+ used and OEM parts for that matter), better forks, factory rear disc, and more.  If you plan on keeping the bike a long time, why start with something that is difficult to find reasonably priced parts for?

Good points and IMO the stock drum is a good brake as far as dirt bike drum brakes go, I've had worst.  I did the conversion as part of a weight reduction project, and I ride in the wet PNW where the water susceptibility of drum brakes for water fade is a real problem. 

[Redpoint]

I'm a bit surprised about the susceptibility in the wet.  I'm in BC, so our climate is almost identical (if comparing directly north/south).  Never had a problem with riding the drum brake in the wet.

 

However, I should state that I'm coming from a DH mountain biking background, and I use a trials tire.  So, I'm used to using the back brake mostly for cornering and having it lock-up quickly anyways regardless of drum or disc on the rear.  Though on the mountain bike it doesn't lock-up nearly as easy (disc brakes, knobby tires).

 

 

Love this forum.  Always nice to have another perspective.

[XR250rdr]

I did the conversion 7 or 8 years ago and definitely prefer the disc to the stock drum.

 

That being said, it would really depend on the cost of parts whether I would do it again. I think I only spent maybe $150 to do it.

[rideredfred]

I did the conversion 7 or 8 years ago and definitely prefer the disc to the stock drum.

 

That being said, it would really depend on the cost of parts whether I would do it again. I think I only spent maybe $150 to do it.

y

I did the conversion 7 or 8 years ago and definitely prefer the disc to the stock drum.

 

That being said, it would really depend on the cost of parts whether I would do it again. I think I only spent maybe $150 to do it.

y

[rideredfred]

All valid points I think I will give it a go can't help my self I love to tinker around with ol bikes just to see how good of a machine they can be