hi i have a 2002 raptor 660r i recently rebuilt the carb and added a DG RCM II Black Slip On Exhaust w/ Spark Arrestor. the quad ran great befor i put the new exhaust on. it pops and backfires alot now i have to run it with the choke on or it will stall and if i let off the throttle it will stall iv read alot of stuff and it all ses that my jets are not the right size. when i rebuilt it i did so with stcok jet size.
if i need bigger jet can any one tell me what size i need. its a double bowl if you need any other info please ask

 

if you get a stage 1 moose jet kit should fix that

 

will these work

Dynojet Kit Dyno Jet Yamaha Raptor 660 01 05 Free SHIP | eBay

 

that should do it

 

awesome any recommendations on jet size?

 

my elevation is 451 ft.

 

Stop riding it, you are showing signs of a lean condition
Your will roast your head if you keep riding
Start with 2 sizes up on main and 1 size on pilots minimum but you might even have to go higher on the mains. They are cheap you can buy them from Vito or at your locale race shop. It's good to have extra big and smaller jets on hand,to adjust for temp changes if you ride all year long anyway
I can help you but I need to kno what jets are in the carbs. Now?
Do you know how to plug chop? It will help you dial in your jet perfectly
Also take the lid off the air box and are you using premium fuel. You should be.
Make sure your bowl heights are set right when you take the carbs apart to check.
Also check to make sure your spark plug is not fouled and clean.

 

these are the spec for my carb from the manual
i do not no how to plug chop nor have a heard the term before
i was told there was premium fuel in it when i bought it.
and i just ordered this plug 1 NGK IRIDIUM IX SPARK PLUG DPR8EIX-9
my elevation is 451 ft.



Main jet (M.J) Carburetor #1 : #140 Carburetor #2 : #145
----
Main air jet (M.A.J) #130 ---- Jet needle (J.N) 5ND16-56-3 ---- Needle jet (N.J) P-6M (#826) ---- Pilot air jet (P.A.J.1) Carburetor #1 : #80 Carburetor #2 : #150 ---- Pilot air jet (P.A.J.2) 1.3 ---- Pilot outlet (P.O) Carburetor #1 : 1.0 Carburetor #2 : 0.9 ---- Pilot jet (P.J) #22.5 ---- Bypass 1 (B.P.1) 0.8 ---- Bypass 2 (B.P.2) 0.8 ---- Valve seat size (V.S) 2.0 ---- Starter jet (G.S.1) #95 ---- Starter jet (G.S.2) 0.5 Throttle valve size (Th.V) #80 ---- Float height (F.H) 13 mm (0.51 in) ---- Fuel level (F.L) 3 ~ 4 mm (0.12 ~ 0.16 in) ---- Engine idle speed 1,450 ~ 1,550 r/min ---- Intake vacuum 32.0 ~ 33.3 kPa (240 ~ 250 mmHg, 9.45 ~ 9.83 inHg)

 

he didnt want to help huh??