Trottle Response Question

[JustinB]

I have noticed after riding my 03 800 that my throttle response on my 02 is lagging, you hit the throttle and its goes BRRRRRAAAAAAAAAAP. When the 03 Is on it BRAAAAAAAAAP.(my best vocals) What could this be? I like the snappy response.

 

[Summit8]

Make sure the heated carbs on the 02 are off, replace the non-hooded needle jets and the non adjustable 9ZLY6-58 needles to 9dfm2-59 needles. Needle position-2,change pilots from 17,5 to 15.
Probably close to what the 03 carb calibration changed to, mine were rebuilt by Xtreme Performance in Colorado. They used to do this and I think they still have the info for their 02 setup on their website, although they no longer perform the service.
The 02 DPM setup was also rich, I did away with the DPM, and the carbs are vented to the airbox, alt. compensation is handled by a set of Jack Harris Power-jets. This got rid of the BRAAAAAPP and cleaned up the lean midrange heat problem as well.
Alot of the Doo tuners out there know this setup, Big John knows of this setup & I'm sure Kelsey at RKT could steer you to the right setup for your 02. I'd just find a set of 03 carbs, get rid of the DPM, etc.

Basically, the 02 carb setup was junk from the factory, plus the 800HO motor in your 03 has a little more snort, porting is a little different.

Be back next Thursday.

 

[Vailguy]

2nd the hooded needle jets. I was running HO cylinders in my 01 and ran hooded carbs. I ebayed some 03 carbs for $80 bucks and jetted down the response difference was dramatic. Not to mention, probably saved the $80 in fuel alone from the jetting difference.

 

[JustinB]

Thanks guys awesome I have a spare 03 carb kit. Dumb question what is the dpm and what does it do? Also the guy that built this sled used after market hoses to hook up the carb heaters and I cant turn them off??? should I install an on off switch?

 

[Vailguy]

the dpm adjusts the fuel for change in altitude. As for the carb heaters, you ride in Utah so you don't need them goto the auto parts store and get two vacuum caps. One will go on the head barb and the other one will go on the coolant barb, zip tie them on securely. Remove all the hoses in between these and the carb.