Need jetting input, new fresh combo/engine

[BIGONTS]

Ready to fire up my new engine and I have an idea about what jetting I should start with, but would like some expert input from some of you on this forum. Thanks,

 

I ride mostly in IL and MI. About 500-600 sea level.

 

Here is my combo:

Stock carbs with tors removed, no airbox, K&N clamp on filters

Stock spec bottom end

VF3 reeds

Trinity stage 3, dune and trail port, 64.5 pistons

Trinity IV head with 20cc domes

Timing at +4

T5's pipes

Stock boost bottle, also got a White Brothers one. Should I use it?? Or, are they BS

NGK BR8ES gapped at 33

Run 93 octane gas all the time

 

This is what I have so far.

Main Jet 340, possibly step down to 330 if it bogs at top end, 6th gear? or needle adjustment?

Pilot 30, maybe a 27.5??

Needle on 3rd notch from the top

Air screw 2 turns out??

 

I plan on fine tuning it after a few breakin heat cycles and short low rpm rides. Anything I should be looking for?

 

Thanks again

Edited May 5, 2010 by BIGONTS

[BIGONTS]

Wow, no replies? I'm sure I got the right forum

 

Got an updated and I have been working with Joe from Trinity. The guy is awesome.

 

I got it running and broken in through a few heat cycles. Started getting on it and it runs awesome. Like Joe said with this port, the power hits suddenly and it goes, not gradually, and is kind of either on and off. Can't wait to get it on some sand.

 

However, it does not pull all the way to the top like before. Right, right at the end of the gear, it stops pulling. I think it is rich because it kind of bogs. Not lean, because it does not keep reving up top, or revving high & fast with no power.. Would I go down a main jet size or drop the needle?

 

My set up:

340 main

30 pilot

3rd clip, middle, down from top, stock needles

 

Let me know what you guys think. Thanks

[mitch350]

Hi !

 

I have almost the same setup as you . except my dome are 21 cc and I'm running 91 octane gaz,open air box no lid K&N pod.

 

right now I use 320 and it's perfect for my elevation (sea level) and my climate 15 to 25 celcius degree (Québec ,Canada).

 

plugs have the perfect color and no bug when I drive .

 

I hope that can help you .

[BIGONTS]

Any other input on what my next adjustments should be? I'm thinking about going to a 27.5 pilot and 330's??

[98_shee]

You sound like your pretty close on the jetting. Start with the 330 or even try the 340's and work down you alway want to start rich, 27.5 pilots and go from there. Needle in middle clip, air screw 1.5-2 turns out.

[BIGONTS]

Got an update. I went down to 330's and that resolved the top end issue. Pulls stronger and longer and through the entire grear now. Might try the 27.5 pilot? It idles great, but how do I know if it's idling rich?

 

The way I understand it, the pilot is for ideling and lower throttle response. Mid throttle is handled by a combo of the air screw and top throttle by the main jet and needle??

 

Bike rips now either way. Thanks.