08 450 exc emission removal

Ive had my 08 450 exc for 2 months. I rode it stock first and knew it wouldnt be right but I wanted to do each change and ride it so I could feel the difference. First, I did gearing went to a 14/52 and 14/50 both are great. Second, I did the jd jet kit and that was really GREAT. Then third I removed the choker out of the muffler and that really helped with the broadness of the power (some say taking that choker out didnt do much, they got to be nuts) each gear pulls twice as long. Now my last thing I need to do is remove the emission parts but my question did it really make any difference? With emission crap on the bike jd says to leave the stock 48 pilot in the bike and I did and It runs perfect for me. Without emission hes says put in a 42 pilot and I will because most of you did and say it works great. Please let me know if that last mod really made a difference and if it did what did it improve. To me it doesnt seem like it would do to much but then again I didnt think these mods I did already would be such an improvement. Thanks for anyones helps, Mark

Removing the charcoal canister doesn't really do much for performance. It is more to clean up the bike and get rid of all those hoses. Just a lot of crap hanging on the bike.

I agree you will likely not notice a performance difference removing the evap system. It allows some unmetered air to bypass the carb, that's why the jetting is different.

The only serious drawback of the system is that the catch can may fill with fuel and then the bike will run bad and/or refuse to start. So you have to drain it periodically or leave the drain plug off. Putting a loop in your float bowl drain line can eliminate a lot of the overflow and help keep the catch can from filling with fuel. Just get a longer line and make a loop in it, with the top of the loop below the throat of the carb.

A minor drawback is that the KTM QR skid plate is not QR with the catch can installed, You have to dismount/mount the can every time you pull the skid plate.

I did not like all of the extra junk on the bike, and wanted the convenience of the QR skid plate so I removed the evap system. I put a loop in the float drain line as described above to reduce the amount of fuel sloshing out of the bowl and onto the trail.

Does the stock chain length work with the 14/52?

no needed 118 links

i actually found 13-52 to be perfect with on 450.. the stuff i ride i was on the clutch to much with 14-52.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now