engine hesitation

[billp117@gte.net]

Does anyone have any suggestions about my KLR650 engine problem. When I cruise down the road at about 3000 - 3500 rpm, the engine hesitates...just kind of a slight "jerking" can be felt. It does not seem like anything more than just a moment of gas starvation or maybe weak spark? I just dont know. It ran fine for the last 1500 miles...this is a recent problem. The shop says it is jet related. I rode the bike from 0 - 4000 feet elevation the other day, and it did not change the hesitation much. Can someone on the KLR list give me some suggestions? I have just crated the bike up for shipment to China...and I would like to take the necesary parts with me to fix the mystery hesitation problem. Thanks I advance for your assistance. Bike Stats: 1997 KLR650 (8000 miles), Valves check 1500 miles ago, with Stage I Dynojet kit, Bill Pratt, Mill Creek, WA

[BCDIRECT@enetis.net]

For those who remember my previous posts... My enricher O-ring came in. If yours goes bad or is lost sometime in the future, I recommend you buy this from the factory rather than get an O-ring the same size. This ring is flat on one side and round on the other. It's also elongated to cover the length between the cover and the carb. It is an exact fit on the carb side. Cost $4.95. Anyhow, I installed it and the pilot o-ring I was missing. Also double checked everything else while the carb was off again (5th time). The diaphram T units' rubber is in good shape and the spring seems fine. All the ports in the carb are clear. Paid special attention to the port between the enricher cover and the throat of the carb were the lean condition is suppose to be relieved by extra fuel during engine breaking. All clear. Also checked the float height, it is 17mm from both sides of the float. Put it back together and it STILL backfires under engine breaking conditions. Pilot screw was set at 1.5, 2, 2.5. and 3 with no changes in the pop pop pop under engine breaking. Exhaust mounts were loosened and tightened first at the head and then back. No difference. I did also have an idle fluctuation problem that seems(?) to be fixed, but it is a problems that comes and goes. Nothing consistant. Had no problem with the idle today. Bike runs great otherwise, good acceleration, strong mid and top end, no backfiring when I shift or back off momentarily, just under engine breaking conditions. Where do I go from here? Any thoughts?