Just bought a 96 KDX 200 that's all stock. The previous owner told me it didn't run very well and hence I got it for a very good price.
Here's the problem - the bike won't idle. I've got the throttle stop all the way in. Also won't pull cleanly to redline. It's obviously loading up and rich (black spooge and fouling plugs), but I can't seem to figure out why.
Here's what I've done and checked so far -
Drained fuel tank and mixed fresh gas with yamalube R @ 32:1
Cleaned carb. Checked pilot and main jet for blockage. Checked all the circuits with carb cleaner to make sure they were clear.
New float needle and seat
Checked floats - they still float :laugh:
Main jet - 155
Pilot jet - 42
Needle clip - middle slot
Air screw - 2 1/2 turns out
Float height - 16mm
Compression - 150psi
New NGK BR8ES (several ;) )
Cleaned the air filter.
Checked for cracks around intake boot. Sprayed WD-40 around with bike running, but no change in RPM to indicate an air leak
Pulled the flywheel cover to see if there was evidence of a crankshaft seal leak, but I don't see any black stuff there. I don't appear to be losing any transmission oil either.
Looking through previous posts, it appears I'm pretty close on the jetting. I started jetting down on the main jet today just to see what would happen. The bike ran a little better for every size down I went. When I got to a 138 the bike pulled cleanly through to redline. I'm sure if I go with a smaller pilot jet, I'll get it to idle. I'm afraid I'm headed down the wrong road by jetting that far down. A 138 main jet seems to small to me. I suspect I would just be covering up a problem. I'd rather fix it correctly.
I've exhausted my knowledge. Anyone have an idea?
Here's the problem - the bike won't idle. I've got the throttle stop all the way in. Also won't pull cleanly to redline. It's obviously loading up and rich (black spooge and fouling plugs), but I can't seem to figure out why.
Here's what I've done and checked so far -
Drained fuel tank and mixed fresh gas with yamalube R @ 32:1
Cleaned carb. Checked pilot and main jet for blockage. Checked all the circuits with carb cleaner to make sure they were clear.
New float needle and seat
Checked floats - they still float :laugh:
Main jet - 155
Pilot jet - 42
Needle clip - middle slot
Air screw - 2 1/2 turns out
Float height - 16mm
Compression - 150psi
New NGK BR8ES (several ;) )
Cleaned the air filter.
Checked for cracks around intake boot. Sprayed WD-40 around with bike running, but no change in RPM to indicate an air leak
Pulled the flywheel cover to see if there was evidence of a crankshaft seal leak, but I don't see any black stuff there. I don't appear to be losing any transmission oil either.
Looking through previous posts, it appears I'm pretty close on the jetting. I started jetting down on the main jet today just to see what would happen. The bike ran a little better for every size down I went. When I got to a 138 the bike pulled cleanly through to redline. I'm sure if I go with a smaller pilot jet, I'll get it to idle. I'm afraid I'm headed down the wrong road by jetting that far down. A 138 main jet seems to small to me. I suspect I would just be covering up a problem. I'd rather fix it correctly.
I've exhausted my knowledge. Anyone have an idea?