Jetting for stock pipe w/o spark arrestor?

[Ridin' Jesse]

what would i use for jetting it?

[WhiteZee]

you dont need to rejet.

[RedRacer44]

On my cousins 450R, we took out the spark arrestor, took the airbox lid off, and just put in a 185 main jet w/ 2 turns out on the air-fuel mix screw. It ran great......

if u leave airbox lid on then you dont ned to rejet...a 18 is a little extreme i would think

[Ridin' Jesse]

i def. need to rejet...its harder to start and it backfires now so i think im gonna rejet before racing, and then when i get my aftermarket pipe ill rejet again.

[WhiteZee]

Originally posted by Ridin' Jesse
i def. need to rejet...its harder to start and it backfires now so i think im gonna rejet before racing, and then when i get my aftermarket pipe ill rejet again.
did you remove your air box lid?

if you only removed the sparky, you do not need to rejet.

[TRX250R87]

I have the lid removed with an HRC type end cap with 170 main and pilot turned out an extra turn. Runs good.
ERIC

[Ridin' Jesse]

Originally posted by WhiteZee
did you remove your air box lid?

if you only removed the sparky, you do not need to rejet.


nope lids still on only the s/a is out...but it still backfires n stuff

[WhiteZee]

when you say it back fires, do you mean it pops on deceleration? if thats whats happening, you need to turn your air/fuel screw out some.

[exrider44]

I have my lid off with the arrestor out and I rejetted to 185 I was told to change the positon of the clip on the needle to the 4th setting with stock. The hrc needle go 3rd clip. Which Im going to order. I have it at 180 before and it didnt run right it stalled alot backfired. Had a choked up feeling when I hit mid top end. Now with the 185 it has alot more snap. I still need to adjust my fuel screw also.

[trx450r05101]

set mine up the same...s/a out, lid off 185, main. It rips...lots of torque. being so cold here I didnt have to touch anything else..I will re-jet with pipe and pro flow kit in the spring..