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07 Jetting

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I know this has been covered a few times and I have looked and researched it all, but still can't get it right.

 

Currently jetted at 42 pilot, 145 main, JD red needle in the 5th position, unknown leak jet  (JD kit installed per instructions)

 

screw is 2 turns out, but turning it doesn't seem to make much difference.  Bike is stock except for FMF muffler

 

Bike starts fine, hot or cold and runs good, except for low end bog and hanging idle.  I had a 45 pilot in it, which really bogged it out, but idle did not seem to hang as bad.

 

Bike gets real hot and will start to push coolant out overflow if left to idle to long.

 

Where do I go from here?  Valves have been shimmed, no  vacuum leaks.

 

Am I too rich?  I was thinking about changing to the 08-09 needle and jetting, but all the posts end with no feedback about how it worked out for those that changed to it.

 

Thanks

Pete

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Overheating quickly can mean running too lean, or worse stilll, leaking head gasket, where combustion gases are pressurising the coolant.

It can mean a twisted cam on this bike which is a lean condition. Unless he is loosing coolant it's not the head gasket.

 

Most four strokes will push coolant out when idling for a while with no air flow through the radiators.

Not on this bike if everything is correct. Our bike can sit for 15-20 minutes without any overheating. Only time we had an issue with overheating was when the cam twisted.

Edited by weantright

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I know this has been covered a few times and I have looked and researched it all, but still can't get it right.

 

Currently jetted at 42 pilot, 145 main, JD red needle in the 5th position, unknown leak jet  (JD kit installed per instructions)

 

screw is 2 turns out, but turning it doesn't seem to make much difference.  Bike is stock except for FMF muffler

 

Bike starts fine, hot or cold and runs good, except for low end bog and hanging idle.  I had a 45 pilot in it, which really bogged it out, but idle did not seem to hang as bad.

 

Bike gets real hot and will start to push coolant out overflow if left to idle to long.

 

Where do I go from here?  Valves have been shimmed, no  vacuum leaks.

 

Am I too rich?  I was thinking about changing to the 08-09 needle and jetting, but all the posts end with no feedback about how it worked out for those that changed to it.

 

Thanks

Pete

JD uses a leaner needles so you can't use the same jetting spec as OEM. Hot is lean not rich in most cases. What you have listed looks good, try lowering the idle a little. If this has no change, verify the pilot jet is clean, valves are in spec and look for any carb boot/hot start,,,, leaks.

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Ended up with a 42 pilot, 138 main, NMQS needle, 3rd position with the clip, 58 leak jet, 2 turns out on the fuel screw.

 

Previous owner had 45 leak jet, made a big difference to baseline it on the 2009 jetting then change the pilot.

 

Was running great until the fuel screw vibrated out after 15 miles of logging road.  Luckily I found the screw and spring and made it back to the truck

 

Ordered an R&D flex screw to solve that problem

 

Pete

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