500 forks on 250

[n8Rod]

Hey fellas, so I got a 2002 ex500 parts queen, and it seems the forks are the first to be swapped. I have the forks off and left the triples on the 500. Aside from the obvious, what issues am I going to run into doing this swap? I want to keep my 250 wheel, is that possible? What about rotor, speedo cable, fender, axle, brake lines and things like that? You guys are amazing, thanks bro' s.

[spent_too_much]

I thought that the point of a 500 front end swap was for the 17" wheels? Should be a direct swap, if you use all of the 500 components on the 250. You might need different bearings for the tripple. Check out http://www.allballsracing.com for those. They have a conversion part of their site that should get you the right set up! Good luck!

http://www.allballsracing.com/index.php/forkconversion

[InvisiBill]

The Gen2 500 is a lot closer to the NewGen than the PreGen. Any differences that need to be accounted for in a NewGen swap should be pretty similar for a 500 swap as well. Like spent_too_much said, these swaps are usually done to get the 17" wheel, so they're usually pretty complete swaps.

The 500 fender doesn't wrap around the forks the way the PreGen fender does - it bolts to tabs in front of and behind the fork leg, so it wouldn't surprise me if the fender won't swap. The axles are different too. The PreGen uses a big "bolt" with a castle nut to go through the forks and wheel. The 500 axle doesn't extend past the outside edge of the forks, and is pinched in by allen bolts in the bottom of the fork legs. The brake caliper mount looks similar, but I'm not sure how close the measurements are. The 250 has a piece with tangs that clips to the wheel to drive the speedo, while the 500 has tangs built into the wheel itself. When I put the aftermarket 250 wheels on my 500, the other guy who did it first said that the 250 speedo drive was needed to match up to the 250 wheel (I believe him, though I never personally tried to make the 250 wheel and 500 drive work together). The alignment tabs are slightly different between the two, so I had to Dremel the 250 drive's plastic a bit too.

It's not a great pic, but this may help visualize some stuff. You can just barely see the allen head of the pinch bolt in the front of the fork leg.




That being said, there's nothing special about the 500 forks. They're 37mm like the NewGen and have slightly stiffer springs than the PreGen (still softer than the NewGen though). The springs can be transferred to the PreGen forks if you're just wanting to stiffen it up. Otherwise, they're the same basic technology.

It seems like a lot of work for very little change in the end.