525 exc....jd kit fitted..still not quite right

hi james..got your kit in 4 days from usa to uk..many thanks..great service...fitted as per instructions..iam at virtually zero feet altitude..and low/cold uk temps..set blue needle at 3rd clip..172 main jet and screw is 1 3/4 turns out...bike runs fast at idle with kit fitted...and does not seem to pull as well as it could in the midrange and when i get to full throttle its not happy at all..it stops pulling..very reluctant..and i have to back off to pick up again..its hard for me to say whether it needs more fuel at full throttle or its too much..plug check seems normal light brownish but i cannot get the bike to run at all well at full throttle to get a decent run for a proper plug check..any ideas...forgot to add i have a powernow intake blade fitted..would this be the problem? thanks

i cannot get the bike to run at all well at full throttle to get a decent run for a proper plug check..any ideas...forgot to add i have a powernow intake blade fitted..would this be the problem? thanks

Try lowering the main jet, having a plate in the venturi reduces airflow. The kit has a selection of smaller main jets to use.



hi james..i have lowered the main jet...i have tried the 172, 170, in fact all of them but no good...approaching full revs it just fluffs and cuts out..throttle off into the midrange and she starts to pull again...does not seem to be pulling as well as it could in the midrange but this could be the area of overlap into the territory of the main jet..i have checked all the seals ie air filter, carb intake..i have sealed the header pipes to the head (popping now gone on deceleration)...iam stumped..any thoughts would be much appreciated...

..any ideas...forgot to add i have a powernow intake blade fitted..would this be the problem? thanks

The full throttle is on the main jet and is not a range that should be a problem tuning, it's a simple passage thru the main ciruit of the carburetor. This sounds like different type of issue. The Power-Now may need a smaller main jet like 168, or else you are hitting the rev limiter.

Did you just install the Power-Now? Check that the air jets are clear in the intake bell.



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