KDXRIDER.NET

Somewhere I read that doing the standard KX250 fork conversion on a KDX200/220 will raise the front slightly higher.... so just curious if anyone has laced a 19" rim the the rear hub to get a bit more height at the back of the bike to balance out the extra fork height. I guess I'm also asking just because I like the idea of a 19" rear and curious if anyone has done this? Swingarm clearance looks like it might be tight. Comments?

I believe a 19 rim and tire and a 18 have the same overall diamater. The 19 are a lower profile tire.

royadams wrote:I believe a 19 rim and tire and a 18 have the same overall diamater. The 19 are a lower profile tire.

Correct on that.

If you are woods riding, you are better of with the 18" wheel.

The KX fork conversion I did would have raised the front end considerably if the top of the forks were left flush with the top triple. KX forks are longer. Most, including me, raise the fork tubes in the triple to get the front end back down. I also had bar risers with tapered bars, which enabled me to put the forks where I wanted them. You can also put a 110 rear tire on instead of the 100 to raise the rear slightly, but I'd def stick with 18" wheel for trail riding. My experience, FWIW. Awesome 450 build, BTW.

Frame maker - you have the skills and tools to shorten the forks. It really isn't that difficult.

If you raise the forks too much in the triples, your tire could hit the fender before you run out of travel.

Tedh98 wrote:If you raise the forks too much in the triples, your tire could hit the fender before you run out of travel.

Good point. That is something to be careful of.

Thanks everyone for the feedback. I hadn't done enough research to realize the overall diameter on the 18" and 19" tires would be the same... note the lower profile of the 19" tires. Sliding the forks up in the triples seams the obvious solution. Upping the pre-load on the rear shock might also help a bit. Anyway, the suggestions are all helpful and appreciated.

And thanks Turtle for the props on my 450 build.

Tedh98 wrote:Frame maker - you have the skills and tools to shorten the forks. It really isn't that difficult.

If you raise the forks too much in the triples, your tire could hit the fender before you run out of travel.

I've done five USD fork conversions for KDX's and simply raised the forks to get the right geometry. Standard fatbar converters raised the bars enough to clear the fork tops. In each case, I set the oil level to get maximum fork travel and even so, have never had a fender clearance problem and the forks work as they should from the factory with just a retuned compression stack.

Shortening forks can be problematic, as it's hard to find springs of the correct length and rate to fit. Most guys who do that (like short trackers) either get some custom made or some trial-and-error with cutting softer springs.

My bike's forks average about 1-1/8" from the top of the triple to the top of the fork cap.

Nice bike you made! No suspension....I would have croaked!

Properly shortening forks (when you need to shorten them an inch or two) doesn't involve cutting or altering the springs.

Tedh98 wrote:Properly shortening forks (when you need to shorten them an inch or two) doesn't involve cutting or altering the springs.

How do you do that? Just curious...I've shortened by putting a short spacer over the cartridge rod, but then the spring preload is too much. None of the forks I've had have had any spacers above the springs you could shorten to compensate.

I've just relocated the spring seat to give the correct preload.