Just picked up a 2009 KLX250s Dual Sport off CL. It's only got 700 miles on it and has never been in the dirt...until I got it home!
When I test rode the KLX, it was so gutless that I thought something was wrong with it. However, I soon discovered after reading through the forums, that the bike is totally corked up to pass CA smog requirements. So, I installed a DJ stage 2 jet kit, removed all of the extra canisters and hoses, then made up a block off plate for the upper breather pipe.
The trick was getting from the old part with the hose to a CAD file of the part. After playing around with pictures and editors and trying to figure out a way to get the aspect ratio correct, I finally drew up a fiducial, printed it out, then placed it on the bed of my scanner and took a scan of the bottom. Here is what I ended up with:
The fiducial mark is exactly .5" round, so I played with the scaling of the picture until I got it scaled correctly in TurboCAD, then I drew around the outline of the housing to come up with the outer profile of the plate.
I ended up adding back in some material to the sides to make the plate stronger, so the real part looks more like shown. After that, it was off to the CNC to cut out the prototype!
The part fit perfectly, although the stock bolts are a bit too long. Just need a few washers to space things out a bit. I've got a few extra if anyone is interested. $20 plus shipping from 95662.