Jetting with the airbox lid off and spark arrestor removed

[exrider44]

Does anyone know If I will need to change my jetting if I remove my airbox lid off and take the stock spark arrestor out. If so someone please tell me what jet to use thanks!

[Blown 331]

You will have to rejet for sure. You have a 118 now, I would say try a 180-185 somewhere around there.

[exrider44]

Thanks alot for the info I appreciate it.

[exrider44]

Blown 331 are you at sea level and what temp are you riding in just curious?

[ZRider400]

when mine was setup like that i ran a 170 main and fuel screw turned out a tad more than stock.

[Blown 331]

Originally posted by exrider44
Blown 331 are you at sea level and what temp are you riding in just curious?

I'm near St. Louis. About 535 feet about sea level. It's in the 80's today.

[JDH]

I have a dynojet 180 in mine. I have a whitebrothers full system and airbox lid off with the air/fuel screw turned out 2 1/2 turns. I ride at sea level and up to about 4500 feet with no problem.

[Seano]

i removed my spark arrestor for the dunes this weekend also. noticed more bottom end. how much more power from opening up the airbox and rejetting the main, running without the baffle?

[TRX450R2]

At least 5hp-7hp gain on the dyno:)

[RedRacer44]

We've had success with taking the spark arrestor out, removing the lid, and jetting up to a 180-185 main jet. Its nothing like putting a slip-on or full exhaust on.....and shouldnt be a permanent thing because it sounds like crap but its a quick fix for a couple HP. We've also put the HRC end cap on the latest '05 TRX i'm building and did the same thing as far as jetting....it ran better also but still sounds like crap. The HRC end cap looks a lot cooler than the factory crap. Oh well, there will be SPARKS flying from that quad soon enough in the exhaust department :devil: