new FMF power bomb pipe and more Jetting Q??

after smashing my KX450 pipe i bought the FMF head pipe. The bike has a dead spot from idle. The bike ran great with the kx-f pipe after i drilled the main jet. But now it has a dead spot when i go to rev it from idle.

What do i have to change?

Does the stock needle have extra groves?

Here is the list of mods i've done

FMF power bomb head pipe

KX-F muffler

applied ais delete

removed metal air screen from the air box

I have an FMF Powerbomb header with an FMF Powercore can. I'm at sea level, with the airbox snorkle removed and the the AIS taken off the bike.

The JD jetting kit was the ticket to joy for me. I'm running the 170 main jet, and the red needle, with the clip in the middle position. The bike runs perfectly, with no dead spots, no bogging, no surging, warms up quickly, and runs much cooler than stock. Goes like stink, too. And I didn't even have to touch the fuel screw.

Some folks complain that the JD kits cost a little too much, but to me it was more than worth the ease of installation and desired results. Plug and play.

:thumbsup:

Can the accelerrator pump be adjusted?

Can the accelerrator pump be adjusted?

The JD jetting kit comes with two different tension o-rings to adjust the pump squirt.

don't get how o-rings are use to adjust the pump

They are basically used like glorified rubber bands, on the linkage...

There's more info on how to make other adjustments to the pump, here...

http://www.jdjetting.com/html/faq.htm#3

Edited by DRZ400SK4

i just changed the pilot jet from a 45 to a 50, and that fixed the glowing red hot header pipe and most of the stumble.

Does the main jet only have to do with upper rpms?

Main is only relevant at 1/2 - WOT

Does the stock needle have extra grooves?

Yes....you can raise and lower the clip on the needle to lean/richen the carb.

Does the stock needle have extra grooves?

Yes....you can raise and lower the clip on the needle to lean/richen the carb.

Does it richen the carb from low and high rpms?

Do u think i should lower the clip to help fix the stumble?

I believe only Aussie models have adjustable needle. I put a kxf needle in mine and a r&d power bowl. Love it.

My stock needle only had the one slot. Mine's a Canadian spec model.

Just order the JD kit and make it easy on yourself.

:thumbsup:

Can the accelerrator pump be adjusted?

No, it is fixed.

i took the bike for a spin to see how it would react on top end, And the bike runs great. I guess i needed to ride it instead of just reving it. Thanks for the help guys.

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