This is what happens when I stay at home on a Sunday evening ( to much time on my hands )

 

harry, what is your prognosis on why my raptor is sort of lagging when i give it 3/4 to full throttle. i recently opened the air box, added a k+n filter, and jetted to 180/190. it's not a stutter just a slower response. it only does it till my quad gets opened up. it is faster now but this worries me. i have some drags coming up on the 30th. any help would be appreciated. thanks. oh, yeah while we're at it what is your opinion on the best tire and sprocket sizes for 300ft. dirt drags.

 

Please stay home more often Harry. [img]i/expressions/face-icon-small-smile.gif[/img]. Thanks again.

 

Quadgod107
I need to know a few more things before I can recommend any jetting specs. ( operating altitude, average temperature outside, cam specs )

 

Thank you Harry and all others who responded. I live 10 miles inland from the atlantic ocean in south NJ. so it is safe to say i'm as close to sea level as you can be. My motor / cam is stock and will more than likely stay that way. The only airbox mod i have done to date is removing the rubber snorkel. This time of year the temperature averages about 45-50*

 

QUADGOD Give this jetting a try ( stock needle's # 4 - ( left carb 178 )( right carb 182 )
( turn fuel screws out 2 3/4 turns from bottom ) This jetting will be very close. The other problem is the head, The stock head has a problem breathing at the higher rpm's because of the flow characteristics of the stock head. The stock head is screaming for intake work, the exhaust ports on the other hand flows fine. This is the problem, The exhaust out flows the intake ( not a good thing )( get the head ported )

 

Thank you Harry for your time and expertise. Are the jets sizes that you are recommending mikuni or dynojet ? As per my initial post, i am currently running dynojet 146-148 mains and the quad runs real strong. As far as porting, is there a specific stage (amount of material removed) that you would recommend. Once again thanks, your taking the time to post here really speaks volumes

 

QUADGOD
I missed the part about the airbox sorry, You need to open it up more then just removing the snorkel. You need to modify the lid. I left my phone # on a privet post so I can explain how to do this.