what size main jet and pilot ?

[- DUNNY -]

about to have the bike complete in about a day or two. i have

dune/trail port by rb racing

some porting on the transfer cases

rocket pipes

pro design cool head with 20cc domes, altitude where i live is about 1100ft-shooting for 150-155 compression

ported reed cages, boysen 2 stage reeds

stock carbs with k&n pods

+4 degree key

 

just wondered if anyone had any suggestions on what main jet i should start at and pilot. i was thinking 290 or 300 for the main sound right?

 

or any other suggestions on motor mods? i ride fast trails and strip pits.

[GrMeyer]

I would start with 27.5 pilots.

Air Screw 1-1/2 turns from fully seated.

Needle in the middle.

And around 330's or 340's for the mains. But that also depends on how cold you are to.

[98_shee]

I would start with 27.5 pilots.

Air Screw 1-1/2 turns from fully seated.

Needle in the middle.

And around 330's or 340's for the mains. But that also depends on how cold you are to.

 

 

I agree with GrMeyer, 290-300 sounds lean for your mods.

[- DUNNY -]

I agree with GrMeyer, 290-300 sounds lean for your mods.

thanks guys, i wasn't sure what i needed to kick it up to, when i got the bike it was just running t-5's with the 280 mains, i wasn't quite sure how much more i would need to go with the dune/trail ported cylinders. i will be riding in 60-80 degree typical ohio summer weather.

[locogato11283]

start with 320 main and work from there.

 

27.5 pilot for sure.

 

air screw .5-2 turns out depending on throttle response. this will need to be set once the main is correct.

 

needle in the middle position.

[firebanshee]

about to have the bike complete in about a day or two. i have

dune/trail port by rb racing

some porting on the transfer cases

rocket pipes

pro design cool head with 20cc domes, altitude where i live is about 1100ft-shooting for 150-155 compression

ported reed cages, boysen 2 stage reeds

stock carbs with k&n pods

+4 degree key

 

just wondered if anyone had any suggestions on what main jet i should start at and pilot. i was thinking 290 or 300 for the main sound right?

 

or any other suggestions on motor mods? i ride fast trails and strip pits.

I see in your mod list you run a degree key instead of a timing plate, i would rather run an adjustable timing plate than a degree key. I have heard of those offset keys shearing off when you are out riding not very reliable. I would buy a plate and set it to +4. Just my thoughts.

[Fullthrottle02]

start with 320 main and work from there.

 

27.5 pilot for sure.

 

air screw .5-2 turns out depending on throttle response. this will need to be set once the main is correct.

 

needle in the middle position.

 

This is the exact jetting a buddy has with pretty much the same mods as you, he might have a little more porting and v-force, but everything else is the same.

 

This jetting should get ya damn close.