Need Exact performance jets

[put-put]

i have an 05 trx 400 EX with a pro circuit ti-4 slip on and a air filter. what jets do i need to get? exactly cuz my uncle can get them individualy. or whats the best thing to get after jet?

[GPracer2500]

No one can tell you exactly. Jetting doesn't work like that. What you should be asking for is a baseline from which you test with your machine in your environment.

Even if all variables were perfectly identical (and they never are) some people like to jet right on the edge of too lean (for every last fraction of power) while others prefer to stay slightly rich for cooler engine temps.

My suggestion is to buy a range of jets (in your case, maybe 152, 155, 158, 160, 165) and test for the best performance. Once you are satisfied with a decision then that leaves you with a few extra sizes on hand for rejetting as temperatures and riding locations dictate.

A 40 or 42 pilot jet would also be a good idea.

Hope that helps and good luck!

[underpowered]

Originally posted by GPracer2500
No one can tell you exactly. Jetting doesn't work like that. What you should be asking for is a baseline from which you test with your machine in your environment.

Even if all variables were perfectly identical (and they never are) some people like to jet right on the edge of too lean (for every last fraction of power) while others prefer to stay slightly rich for cooler engine temps.

My suggestion is to buy a range of jets (in your case, maybe 152, 155, 158, 160, 165) and test for the best performance. Once you are satisfied with a decision then that leaves you with a few extra sizes on hand for rejetting as temperatures and riding locations dictate.

A 40 or 42 pilot jet would also be a good idea.

Hope that helps and good luck!

well put

no two motors will ever run the same. even witht eh same mods in the same area, two motors may require different jetting. like GPracer said, we can only give you a starting point, you have to fine tune it from there.

[400exstud]

GPracer nailed it. I run my full HMF on either a 152 or 155 depending on the conditions but others like to go much richer than that.