im new to the forum just got a project 2004 kodiak 450 it has a k&n air filter, stock exhast but the baffle was removed and power tip was added, it also has amr stage 3 rev box and 1.5in snorkle. the carb is rebuilt but the jets are stock. It Backfires. Questions

1. Is 1.5in snorkle to small do i need a 2in.
2. What size jets should i run
3.What should the valve clearence be
4. Should i just buy a aftermarket pipe

 

Hmm. I don't really see the point of souping up a Kodiak 450, but it must make somebody happy to do it.

 

your bike is sucking in more air with the k&n but same amount of fuel with stock carb jets, on top of the fact that every atv comes leaned out from japan to begin with to pass tight emmissions, your bike will be running running lean, buy a jet kit from dynojet, the install instructions are easy enough for anyone to follow

use the largest jet in the dynojet kit, usually does the trick, if your snorkel was to small you would be running rich to begin with due to lack of air, take it off your box, rev the bike up see if its any different, if not, its fine