First off, thanks for helping.

I've got a Raptor with K&N Pro-Flow, GYTR slip on (spark arrestor removed), Dynojet kit with needle on 4th groove from top, 146, 148 jets, stock pilots, air screws 3 turns out, EHS racing airbox lid (basically an outerwear bolted on to the stock lid with most of the lid cut away). Gearing is 13/42. I live in Texas and elevation is below 500 feet.

My brother has a Raptor with GYTR slip on (spark arrestor removed), stock jetting, stock filter, stock gearing.

For some reason, his bike pulls harder than mine and he beats me by about 3 quad lengths every race. It pulls noticeably harder in the top gears as well. Both of our valves are adjusted correctly, etc.

I did have 12/40 gearing, stock airbox lid, spark arrestor installed and Dynojet 144/146 jets and we were about even. It just depended on the shift points, holeshot, etc.

I figured I could get him if I upped the jets, took out the sparky and put the cut up lid on. It made me a lot slower with the jets I chose and I also lost a lot of torque.

Help! I should be able to beat him easily with my mods. I figured originally that it was the gearing making the difference but I think its the jetting now.

Thanks a lot.

 

I think you need to drop the needle one notch to the 3rd and that sould help you

 

One other thing, I put the stock airbox lid back on at the end of the day and it felt like it picked up some power. I didn't have a chace to drag race so I don't know the exact result but it did feel better. It sure seems that I should be able to get more power with the correct jetting and the cut up lid though.

Pat,
Thanks. By drop the needle, do you mean move it up to the third notch? Just want to make sure. I'm on the fourth notch down from the top.

Anyone else? I am going to get piston, cam etc. soon but I sure do think I should be able to get a lot more out of what I've already got before then.

Thanks

 

What is your spark plug color!!! Let us know!!!!

 

If you get faster when you put more restriction on the intake (stock lid back on) then that means you are starving for fuel. Increase your mains by or two more sizes. I will bet that makes you alot faster. Good Luck!

RR1

 

Thanks.

Spark plug was a little on the white side, but had some tan. Not too far off, but it looked a LITTLE lean. Would that make that much difference?

What size jets would you guys suggest seem right.

Thanks.

 

slappie


By having lean can rob your hp. so sound like you need to bump up the main jet 2 point or so.

But did you do plug check on full throttle, half throttle. They are couple way of do the plug checks. I would do half throttle and full throttle and both time do the plug check and see where you at fot the neddle and main jet.

good luck.

 

the other guys are right launch the lid and go up in mains
pat