Very bored yesterday.

So instead of vegging out I put some YZ cams in my WR250 I had laying around. My WR is an 03 with a WB pipe and a 262 kit. I put a JD kit in it a while back and it was jetted sharp.

I started the bike up and it barely ran. I wondered if I had the cams indexed right. Then I put the choke on and BRAPPP, it felt great. Much better power.

I put a 185 main jet in it and it helped but the bike would stall when I opened the throttle fast. Putting in a 42 pilot helped as did opening the fuel screw up a bit.

Still not happy so I soldered the leak jet closed and drilled it with a #79 drill (.0145). I take a tiny bit of solder and lay it on the jet and then just kiss it with a propane torch. That seemed to solve the problem. No more flame outs and much better throttle response.

BTW I orderd some 4mm x 12mm stainless steel socket head screws for the float bowl. Made life much easier.

With the 262 kit the original jetting might be a too rich. They will tend to run richer with the bigger kit. Bigger piston,,,,, more vacuum created thus pulls in more gas. I have an 01' with the 262 and have a 175 main with a 40 pilot and for the leak I have a 100 but I also have the P-38 accelerator pump cover so that takes care of the BIG leak jet. If it runs better with the choke out it sounds rich. Check with James Dean on the Jetting forum. He helped me out tons!!! JOHN

That's pretty odd that the jetting was fine with the 262 kit before the cams but that much off with the YZ cams.

If you put the choke on and the bike runs better it means the bike is lean.

The jetting I ended up with was pretty close to what was reccomended in the JD jetting kit.

Closing up the leak jet made my YZF250 run much better too.

These bikes are sensitive, small changes can make a big difference.

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