SSS Forks on a 2001 KX250 - Using KX Wheel and Brake

[Umberto]

I'm currently building a 2001 KX250 with a TX Race body kit, and I wanted to update the suspension to go with the newer style body work. I had read lots of stories about people putting SSS forks on their bikes, but they all used Yamaha parts to do it. I wanted to see if I could use as many Kawasaki parts as possible. I found an article on Vital MX that listed the measurements for the early SSS forks, and the measurements of the 2002 and up KX250 clamps. The early SSS forks are exactly the same size as the two stroke KX forks. This may also apply to the early KX250F as well, but I'm not sure on that.

My bike is a 2001, and that was the last year of the 46 mm forks so I needed some newer model clamps. I found a set of 2003 clamps, but the stem was too long for the 2001 frame. Thankfully the 2001 stem pressed into the clamps without any issues. With that completed, I was able to purchase a set of 2008 YZ250F forks. Once the forks were in, I started the process of seeing what Kawasaki stuff would work with the Yamaha forks. The axle slipped right in, but it was way too long, so I had to order a YZ250F axle and nut. The Kawasaki brake carrier was also too long, so I found a cheap eBay caliper and carrier. I had no intention of using the Chinese junk, but it was cheaper than buying a new part and there were none used on eBay. After I got all the parts in, I found that the Kawasaki caliper would bolt up to the carrier, and both sets of spacers (KX and YZ) were not right. I decided to work on the brake side first, and then worry about the other side once I got the wheel where I wanted it. I started by putting the KX brake spacer in the wheel and checking where I was. It started off way too far away from the lug. To trim the spacers, I rigged up a "red neck mill" using a sliding vice and milling bits from Harbor Freight. I trimmed a little bit, checked it for fitment, and repeated. I ended up with a spacer that was 25.5 mm, which perfectly centered the disc in the brake carrier. I was pretty excited at this point.

When I went to put the spacer in the other side, I eyeballed the opening and cut a spacer. It wouldn't fit at all; it was too wide. After some head scratching, I figured out that the axle shoulder on the left side actually came through the lug and extended to flush with the wheel bearing. All I needed was a little bit of spacer inside the wheel, and I would be good. I ended up using a 5.5 mm spacer on that side.

All through the process, I used my Motion Pro fork alignment tool to check that my alignment was good so that my spacers wouldn't cause any binding of the forks. These measurements should be a general starting point, but I would highly encourage you to start larger and fine tune from there using the fork alignment tool to check to make sure that you have everything lined up correctly. Next up for me is the brake line, and the front end is done.

[Umberto]

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