Exhaust problems

[supermotokx]

Hi all

 As some of you may know, I'm rebuilding my supermoto with the 500 motor in a 250 frame. The engine is fitted nicely now and the only thing left to do is the exhaust (I have full FMF with fatty pipe). And this is where the fun really begins: On the right side of the frame just around where the tank ends the frame is too wide for the pipe to clear (the last part of the expansion bit). I've tryed evrything but as it is now my only option is to cut the pipe. My initial idea was to cut the pipe at the very beginning before it actually expans (cut a triangle piece out and weld it back together), but I'm also considering splicing a 250 pipe together with the FMF pipe to get the usual 250 style pipe.
 Has any of you ever done something like this? Any ideas, thoughts?
 I'll post some pictures of the bike shortly.

Martin

[G-HOPPER]

Here is a pic of a 500 in a 250 frame. It looks like he used a 250 pipe and spliced in the fwd part of a 500 pipe to give it the volume needed. That is what a CR500 pipe looks like. It should work. Please post some pics when you can. I would like do do something like that too someday.