LT racing jet kit report...

[jimbolaya]

Hey all,
Just got my jet kit in from gofasters and I can say "BULLY!". Things have cleaned up nicely from1/8 to wide open. I still have some sputter from
closed to 1/8 so I reduced the pilot to 45 from 48 (airscrew at 3 turns out).
It's better, but I want perfection so in will go a 42 asap. Then I should be able to run the A/S at about 1 1/2 out. all the sputter is gone from the previously sputtered up throttle positions. Yah Whoooo!!! I also swithched to the sunny setting and WOW does this 300 go. I love my gasgas mucho better now!

 

[eff]

Jim,

I usually drop the needle one spot (clip up one) to remove that sputter. What position is the clip in?

 

[jimbolaya]

Hey Eff,
the clip is in the middle position as requested by instructions. I didn't think dropping the needle would clean up the off idle richness that's one reason it isn't already done. thanks for the tip. I'll try that first.
I heard from my local gasgas dealer not to run below a 45 pilot, but if I can't get the airscrew below 2 1/2 turns out I've lost the adjustability of the airscrew to lean out that circuit. I will report back how that adjustment goes.
thanks!

 

[GMP]

Try an #8 slide if it won't clean up with a smaller pilot.

 

[eff]

Hey Eff,
the clip is in the middle position as requested by instructions. I didn't think dropping the needle would clean up the off idle richness that's one reason it isn't already done. thanks for the tip. I'll try that first.
I heard from my local gasgas dealer not to run below a 45 pilot, but if I can't get the airscrew below 2 1/2 turns out I've lost the adjustability of the airscrew to lean out that circuit. I will report back how that adjustment goes.
thanks!

The instructions are based on 60ºF I believe. Refer the the std jetting chart in the manual to change from there.

I was running the 48 pilot, air screw 3 turns and the clip in the middle. I took my bike for a spin after I put on the LTR 126MM links (a couple of weeks ago). It sputtered, and was clearly running rich. I popped open the carb and raised the clip one and turned the air screw to 2.5 turns and things ran smooth.

 

[jimbolaya]

took it out after dropping the needle 1 position. temp around 80. with the a/s 3 turns out it was very close, but I'd still liketo drop the p/j to a 42 and run the a/s about 1 1/2 out which give me latiude for adj either way. I must say over all this jetting set up is very good. thanks Les Tinius!
jetting when I'm finished should be as follows:

mj=178
pj=42
jneedle=2nd position from top
a/s= ~1 1/2
#7 slide

 

[jeffd]

This carb is fine up to 3 turns out on the air screw. Les told me that this carb is designed to have the airscrew in that range. I believe he was told this by sudco (keihin importer for u.s.).

jeff

 

[jimbolaya]

With the 42 pilot and airscrew at 2 1/2 turns temps at 84 deg. the carburetion is more clean, but just after cracking the throttle open it doesn't sputter it's more like a raspy hesitation (It may be just part of the characteristics of the engine). I put boyesen dual petal power reeds on my 200 and that same situation cleared up. Maybe since I have the v force3 reeds it is causing the same lack of super smooth acceleration at barely open throttle position (I don't know)
I do know that everywhere else is awesome. smooth powerful acceleration!!

 

[GMP]

The reeds shouldn't do that, mine runs smooth and clean off idle. Try the #8 slide, borrow one if you can. Start back up to 45-48 on the pilot and middle needle position. The 250s seem much eaiser to dial in with a #7 than a #6. The 300 being a bigger pump may be eaiser with the #8. If the slide is rich the rest is a PIA.

 

[jimbolaya]

Much thanks I'll give that a try!

 

[jimbolaya]

I went ahead and ordered a #8 slide because it can't hurt to have it around anyway. Report to follow after it is installed.

 

[juzzasmith]

Look forward to hearing how you get on with the number 8 slide, I've been having very similar issues with the LT kit. It's damn near perfect but I'd like to know if the 8 slide cures those little niggles.

 

[jimbolaya]

LMAO!! Yea those "little niggles" need to go away!
It makes sense the #8 slide would work because it's just at the crack of the throttle that the, in my words, "raspy hesitation" crops up. I've never had to change a slide before to get perfect carburetion, but there's always a first.

 

[pobit]

That hesitation with the 42 pilot LTR needle#2 178 main is caused by being too lean on the needle straight section diameter. Going to a #8 slide will only make it worse. Go back to the #3 clip with the 42 pilot and 175 main and it will work better. Even in the #3 clip the LTR needle is border line lean at off idle at sea level 70 degrees so don't run the air screw out too far. Other options are CCK#3 for a very smooth power band or a N3EG#3 with a 175 main for a stronger mid to top pull. These are sea level settings at 70 degrees F. oil mixed at 40:1 pump gas 91 octane. If you want really clean and crisp jetting, you need to have the cylinder head cut to reduce the squish and get a cleaner burn. Otherwise the jetting will always be a little dirty in hot weather no matter how you jet it. Dave

 

[skid jackson]

cck#3 is a type of needle??

 

[BIG TOOL]

jimbolaya, try what POBIT says before anything else, he is pretty damn good at this stuff, and the advice he gave you is very good... ( Just my 2 cents )

 

[jimbolaya]

I will certainly check it out. thanks!

 

[GMP]

Yes, try it, should tell you if your roughness is rich or lean. There all different. My '07 runs awesome on what would foul my '03. And yes, have RBD cut the head. RBD also does carb mods that have excellent reviews. I beleive he cuts the slide to an #8 and works from there as part of the package.

The latest LTR needles should be richer in the straight section than previous that were indeed lean.

 

[pobit]

The LTR needles I have are sold as -0 needles and measure 2.66mm in diameter. This needle in my 06 300 was lean in the #3 clip 42 pilot and caused the bike too hit too hard at off idle causing excessive wheel spin. The other two needles I mentioned have a softer off idle hit that works better for picking your way through rocks or roots. The CCK is mellow throughout the entire power band and the N3EG gives the bike a more motcross like feel with a healthy mid range hit and a nice over rev if you use a 175 main. Keep in mind I have the DE ignition on my bike so it is more responsive to leaner jetting. The LTR needle may work fine at off idle with the heavier EC ignition as the heavier flywheel will have a dampening effect on throttle response. I do think the heavier ignition would benifit from the N3EG needle to help the slower reving motor spin up faster. Dave

 

[GMP]

Something doesn't add up. Dave, your LTR needle measured 2.66mm on the straight dia.? That would make it richer than the CCK (K=2.695mm). If you were lean off idle with the LTR needle I would think that the CCK would make things worse all else being equal.

300s are tougher to get perfect plus I think you tend to ride them at lower throttle openings, making those adjustments more critical.

What effect does your ignition map switch have on this? Did you jet for one position or the other?