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Sparks pipe jetting

3893 Views 4 Replies 3 Participants Last post by  TRX450rlude
I just purchased a Sparks header pipe and silencer. I was told by dealer a 185 main jet should be the one to use. I am keeping everything stock for now with air box lid removed. But, Sparks recommends 185 main jet and also backing the fuel/air screw out to 4 turns, and maybe even using a 190.
I put the 185 main in and left all other adjustments alone and removed the airbox lid, it ran fine, but didn't seem to be as powerful as others have said.

Since more mods are on the way. If you could help give other jettings as well. Where is the pilot clip? Where is the fuel/air screw? What all do you have to loosen/remove to turn carb on its side?

Jettings:

1. stock air filter, no lid with sparks exhaust

2. K&N air filter, no lid with sparks exhaust

Thanks
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I'm running a 190 main jet with the lid off, sparks filter kit and jet kit. I have the sparks cam on the way and will keep the jetting the same. I turned my air/fuel mixture screw about 2 1/2 to 3 turns out from all the way in. The air/fuel mixture screw is on the bottom of the carb, facing straight down. Its towards the front of the carb. To get to it just loosen the clamps holding the carb in place in the front and rear on the intake boots and tilt it sideways. Pilot clip? You must mean the pilot jet you don't have to mess with it, that's what the air/fuel mixture screw is for.

Your jetting is based on how much air you are taking in, when you remove the lid you take in more air giving you a lean condition, that's why you have to go with a bigger jet. Jetting is also based on altitude, temperture, and the humidity.
Originally posted by lukester720@May 20 2004, 01:45 AM
I'm running a 190 main jet with the lid off, sparks filter kit and jet kit. I have the sparks cam on the way and will keep the jetting the same. I turned my air/fuel mixture screw about 2 1/2 to 3 turns out from all the way in. The air/fuel mixture screw is on the bottom of the carb, facing straight down. Its towards the front of the carb. To get to it just loosen the clamps holding the carb in place in the front and rear on the intake boots and tilt it sideways. Pilot clip? You must mean the pilot jet you don't have to mess with it, that's what the air/fuel mixture screw is for.

Your jetting is based on how much air you are taking in, when you remove the lid you take in more air giving you a lean condition, that's why you have to go with a bigger jet. Jetting is also based on altitude, temperture, and the humidity.
hey luke, what altitude are you at? what exhaust do you have?
Sparks full system, about 300 ft above sea level.
Originally posted by lukester720@May 20 2004, 08:34 AM
Sparks full system, about 300 ft above sea level.
I havent got my sparks pipe yet...I am really happy with this stock pipe with HRC end cap. I think Im going to spend my money on some nerf bars or something other then a pipe for the time being...I was just curios what pipe you had because I am only running the 185 main jet and was curious if I could go up to the 190....I bet I can...I will have to try it.
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