2003 RM250 /KX500 conversion

[510rider]

Ok guys,

Went out and rode my 1989 KX 500.  I feel like I am on a 85cc frame!  I am 6-2 and it is so cramped.  I guess I have just got use to new style frames. 
So I picked up a 03 RM 250 to do a conversion.  Complete roller with no motor, exhaust, or carb for $200!! (It's even very clean!)  I have head the thread on the 2001 conversion and am hoping it will be a similar task.  My big question is the pipe.  I picked up a used CR500 pipe from a 1996 unit.  I also have a KX 500 PSI pipe that is beat to pieces.  Would it be better to get the CR500 AF Pro Circuit pipe and modify it or try to make one out of the 2 piped I have?  Or any other ideas??

I hate that I am not at home on my 89.  I just Race-Teched the forks also...  But the motor does Rip!!! 

Any advise on this project would be great!!!  I also have the 2 piece clutch cover and compression release on it for what its worth.

Thanks,

510 rider.

[umberto]

I used three pipes on mine (2 CRs and one KX), but in hindsight I could have gotten by with the two pipes.  Use the KX sections until it begins to turn the corner, and weld that to the CR section back to the silencer. Look at the AF conversion FL_Sharpshooter did, I think that is how he did his pipe. 

Mikectanker did the RM conversion that is you were talking about.  He would be a good person to PM about his pipe, as it may be a little different on the RMs versus the perimeter framed KX and KXF. Post lots of pictures, we would love to see how your project is going.

[mikectanker]

use the service Honda kx500af pipe. no mods to the pipe or mounts are needed.

you will need to slightly  mod the silencer to slip into the pipe.

Buy  the cheap hose for the water spigot to loop around.

just call me if you want. I'd be glad to help.
cell 814- 490- 5187

[510rider]

Thanks for the info!  How do I find the Service Honda KX500AF pipe???  I thought service Honda closed??

[510rider]

Is the FMF Gnarly Dessert Pipe the one people are using?  It looks like a lowboy pipe compared to the stock pipe.

[mikectanker]

direct from service Honda. last I knew they were open.. try calling them

[510rider]

Just called service Honda. They no longer carry the pipe. Looks like I am welding!!!

[umberto]

Honestly welding one wasn't too bad.  You might try flipping the water inlet over and using a different hose.  That transfer is where the pipe meets the most interference, and flipping it seems to help.  It looks like this:



That's FL_Sharpshooter's bike, maybe he can comment on where he found the hose for it.  

[510rider]

Got the Jose part #. Also read his build. That is exactly how I thought about doing my pipe. Thanks for the info!!

[mikectanker]

Just called service Honda. They no longer carry the pipe. Looks like I am welding!!!

Looks like I'm going to get armor for that pipe then!

[510rider]

Picking up my rolling chassis tomorrow!!!  Let's get this party started!!!

[mikectanker]

if you don't find an answer in my build thread, don't hesitate to call me. I check the site a few times a day sometimes. then other times I'm working so much I can't check it for weeks. I drive trucks so I can almost always bs  on the phone to help out.

[510rider]

Thanks!!!  I certainly will be in touch.

[FL_Sharpshooter]

Honestly welding one wasn't too bad.  You might try flipping the water inlet over and using a different hose.  That transfer is where the pipe meets the most interference, and flipping it seems to help.  It looks like this:



That's FL_Sharpshooter's bike, maybe he can comment on where he found the hose for it.  

The hose kit that I used is the service honda kx500af kit. You can find them on ebay; they're not cheap, but my conversion went smoothly because of them.

I used three pipes on mine (2 CRs and one KX), but in hindsight I could have gotten by with the two pipes.  Use the KX sections until it begins to turn the corner, and weld that to the CR section back to the silencer. Look at the AF conversion FL_Sharpshooter did, I think that is how he did his pipe.  

In my case, I just used a kx500 pipe and cut it right when it started to angle out of the exhaust port and wrapped around the frame. I then welded the cr500 pipe to it, I did have to bend the bottom mounting tab in my vise a small amount. I also cut the "tail" off the pipe, and rotated it; I also had to bend in the tail a small amount. I also rewelded the tail end mounting piece so that I could run the silencer in the stock kx450 location (that way it's cleaner behind the number plate). In order to run it in the stock location, I had to extend the tail piece out, so I subbed in the same gauge thickness of metal, it worked out nicely. The way my pipe mounts is really similar to a ktm 250 mount. It was a bit of a headache, but I think I could do it much faster if I had to do it a second time.

[510rider]

First set back.....the flu!  Didn't get my roller yet.