Jetting that works, collecting info

[pewterpecker]

I would start with those mains and see how it works.

And go for 25 pilots with about 2-2.5 turns to begin with.

[Flynbyu]

Originally Posted by jerry smith

Ive searched and cant find what i need.
I need a good place to start on Jet size, pilot size, and air screw settings for :

Stock 660, K/n filter, no snorkel, scorpion slip on, Stock needles at 3rd clip...at about 850-900ft ASL

I would guess i could bump the mains to about 155(R?)/160(L?) (mikuni sizes?), but i have NO clue about my pilot jets
And im also guessing 3 turns on the R, and 2.75 turns on the L air screws
Am i close?

On the money man.

Try a 25 pilot, and you're set.

~Brian

[Raptor_09]

Just jetted my 660 for a Yoshi full system I am at 1350ft above sea level and have no lid and went with 148/150(DJ) with 3 turns out on the air screws and she pulls through the gears like a mule!!!

[Bocephus]

ok, i got all my parts installed, but it spits and sputters at low rpm's. just starting out normal in 1st gear i dont notice it very much. but if i race someone and start out in 2nd, about half the time it will cut out when i drop the clutch. the engine will stay running, but i have no power. same goes if i am playing in the sand. if i slow down while in 2nd, then crack the throttle to spin around, if the engine is running slow, sometimes it will just sputter around. i installed a k&n/proflow filter setup, no airbox lid, and sparks big core. went with a gytr jet kit. installed 165/170 mains, 25 pilots, gytr needles with clip on 3rd (middle) notch. i couldnt get it to run worth a shit with the a/f screws out 2.5 -3 turns like everyone else under 3000 ft is doing. i ended up going all the way to 1.5 turns out on both carbs. seems to run fine now, other than the problems i just told you about. spark plug looks pretty good. mayyyybe a hair lean. also, on decel. it will backfire a little bit. not alot, but enough to bug a guy.

ANY SUGGESTIONS? do i need to bump up to 27.5 pilots and readjust the a/f screws? move the needle clips to a different notch on the needle?

[Flyinacez]

02 660R
Location: Buffalo, NY
Elevation: 700 Feet Above Sea Level
Jets: Mikuni
Exhaust: Yoshi RS-3 Complete
Intake: Pro Flo Filter no lid

Pilots: 27.5
Fuel Mixture Screws: 2 1/2L - 3R
Needles: Stock on 3rd clip
Main Jets: 160L / 165R

[backyard_beast]

01 660r
Location: Bogalusa, LA
Elevation: 50 ft asl
Jets: Mikuni
Exaust: HMF slip on
Intake: No lid, air filter screwed to box

PIlots:25's
Fuel Mixture screws:2.25 turns out
Needles:3rd clip
Mains:155/160

[yogib]

Oregon coast. 165/170 mains,27.5 pilots,dyno jet needles third clip from top with factory washer and plastic spacer.2 1/2 out on fuel screws,This was on raptor with pro-flow intake no lid,Yosh full exhaust,big gun ignition,17 oz trail tech lightened flywheel and 12/43 gearing.Stock internals.

[krinkle]

2004 660R
Stock Motor

Location: Ashland, WI
Elevation: 823ft. ASL
Exhaust: Yoshimura RS3 Comp Full Exhaust with quiet core spark arrestor
Intake: Modquad pro-flow kit, K&N filter with Outerwears pre-filter, no lid
Jet kit: DynoJet Stage 2 kit - DJ springs and needles and mains
Needles: 3rd clip
Mains: 146/148
Pilots: 27.5 (mikuni)
Mixture: 2.5 turns out

Runs great for me, I pulled out the quiet core and OMG!! What a difference in sound! I'm not sure If I need to do anything with the mixture screws with the core out. I have another quiet core, I think I'm going to chop it in half and see how that works. As much as I would love to run with the core out, I would be begging for a ticket.

[Daves Raptor]

I have a 2003 stock motor & I put a modquad with a K & N Filter, RS-3 full yoshi exhaust, and DJ Jets. I wanted to do the Clear Tube Method. I have read through MANY posts and really didn't see anything, but can anyone give me a good starting point for jets & Pilot? Should I rejet and then do the clear tube or is doing both at the same time fine?

[Hammo686]

do one at a time
at the top of modifications for 660s there is a dumbed down way to do the clear tube