when i let my raptor pull itself along at a very slow pace with no throttle from me (1st gear) and then give a quick full throttle, it stumbles badly for just a second then pulls hard like always. if it has even just a little throttle before i nail it it won't do it. this is what i have tried......
1st-i felt like the jetting was too rich so i dropped down from 180/190 to 170/180 (remember:no lid)with 3-1/2 turn out on the air/fuel mix screws. same.
2nd-i move the clips all over the needle in ever combination possible. both carbs. same.
3rd-i dropped the jets again. 165/170. same. and tried the clip changes again. 2-1/2 turns instead of 3-1/2
4th-dropped to 160/165 seemed better. but not gone.
what now? i was running 150/155 before the air box mods and i know that is way too lean to run without the lid. i also read the report from dirtwheels that one of you guys posted friday i think (sorry i forgot who) but it read...a hard stumble at 1/4 and 3/4 throttle chances are your needle is rich. i take it this article refers to a sigle carb set-up. so which one does this refer to on the raptor? right now i'm at 2-1/2 turns out, #3 clip pos. from the top,(both carbs) 160/165 jets. i ran out of time today to try anything else. all boots are fine and secure. filter too. thanks for any advice.

 

I would almost bet it is your pilot/idle jets. If you have not jetted up on the pilots since all the mods you have made, then that is it. It is way too lean on the idling aspect of it. Actually the pilot jet does control some of the throttle in the very beginning. It's starving for gas at the very beginning before the main jets take over. Try it and see. My 2 cents worth!

 

Check your idle speed. The Raptor has a very fast idle in comparison to other quads. If I turn my idle down where I think it should be by listening to the engine, it will do the same thing if I nail the throttle.

/NotuRaptor

 

What the problem more than liekly is since you have tried changing everything numorous times is your float setting. Its probably set wrong so at lower RPM it is acting rich. Give this a try. It will more than likely cure your problem. If i remember right from when i set mine its supposed to be set so the gas level is 3mm below the float bowl seat. May want to call a dealer for accurate spec on that.

 

Put things back the way they were before you started messing with things, and speed your idle up. It will be fine.

 

RICHIE, make sure and let us know what cures your problem so everyone can learn.

 

i'm going to check it out in just a minute. i'll let you guys know something probably tomorrow. thanks everyone.

 

Richie,

I run 175/180 with stock needles and stock clip position. No lid.

I have recommendations from CT to increase the size of the pilot, but I haven't done it yet.

Let us know how it went,

RM

 

this is your problem.right off idle you get a hiccup,that means your lean.you either need to go the next pilot jet beigger or turn your air fuel screws out about a 1/4 turn at a time and try it.if it does not get better after you have 3 full turns out on the air screw then you need to go up on the pilot and start with 1 1/4 turn out from bottom.
this is the proper way of jetting.not turning your idle up.

 

i didn't have much time today so this is what i did. as far as the idle goes i had to turn it up so far that it was practically drag racing by itself before it stopped doing it. for being lean on the main jets. that's impossible. i was jetted so rich that when i pulled my plug it was soaking wet and black. so i started shrinking the sizes. now i'm all the way down to 160/165 and it's still doing it. i might lean there now but definitely not earlier. anyway, i checked the choke cable. and there is something strange going on there. lately it's been feeling like the switch doesn't go all the way back to fully off. then today when i checked it i slid the choke out but nothing happend till all the way out it just stalled. this was while the engine was running of course. usually after the engine is warm it will start sounding like it's missing while idleing. i'm sure you guys know what i mean. might have something to do with it may not. so if i increase my pilots what size(s) do i need? thanks guys. i'll keep posting along as i go.