XR500 Budget Racer

Well decided to build myself a budget racer based around a 1979 XL500. Taken a lot of inspiration of Dutchspits and Airtime391's threads this is what I have so far. I also have some 43mm CR forks& wheel, and some other bits, which I hope to fit. Going to remove the balancer and fit an XR250 flywheel. Also on the cards is fitting a Suzuki full floater aluminium swinging arm converted for shock mounts. If I still have some money left, I will bore out to 540. So wish me luck :rolleyes:



Edited by chamber66

XL has a loose ballbearing steering head bearings,, seem to remember '84 XR taper bearings fir later stems?

     M2CW,, leave the balance system intact.You're gonna get shocking arm-pump wrestling a heavy bike even with them in.( Have raced one for many years)

      I dont think theres any appreciable improvement in performance taking them out, in fact I reckon it spins up better with then in.

          Whats the first thing a race engine builder does?? Balances the internals.  Vibration robs performance. 

A 250 rotor works great in the dirt. Had mixed results mixing XR rotors and XL electrics,, you may not have spark......

   The XL carb is 2mm smaller than the XR500 carb. may not sound much, but the difference is Big. Fits straight in, till you find an FCR or similar.

Cut the extra snorkel into the top of the airbox.

     Change oil often, with good stuff.

       Dont expect box to last if you're stomping on the lever or powershifting. They only just cope with normal use (its just a tweaked 250 box)

Edited by Muzz67

Removing the balancer is up for discussion, nothing set in stone yet. Carb is going to be a Dellorto VHSB 38mm (it was cheap)


Loosing as much weight as I can on the bike is my biggest priority


Edited by chamber66


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