450r jetting

[Quadracer121]

i got a new 05 trx and i put on a full white bros pipe and i put in the jet that comes with the kit witch is a 162 main jet and it also said to lower the needle clip down one position (richer) and the head pipe still glows and it pops and blowes flames on the lowend when lightly berping the gas let me know what u think thanks brandon

[Old Head]

was the backfire when you hit the gas or on decel after you berp the throttle? Try backing out the fuel screw a 1/4 turn till it stops, but don't go out more than 3 turns.

[Quadracer121]

it backfires on decel at lower rpms and it also blows flames out the back thanks

[400eXr1d3rZ]

Originally posted by Quadracer121
it backfires on decel at lower rpms and it also blows flames out the back thanks

get a 50 pilot jet and turn the fuel screw out 2 1/2 turns

[CRE Performance]

Is your airbox lid still on or is it off? A 162 doesnt sound correct either way for an 05". Its correct for an 06', just not an 05, two different carbs. If you have your lid on, you need to be between 118-130. If your lid is off or heavily vented you need to be between 180-195. Also leave your pilot jet alone at 48, 3rd clip on your needle and adjust your pilot screw accordingly, 2-3 turns out. More like 2-2 1/4 with the lid and 2 1/2- 2 3/4 without the lid.

[04450rrider]

I am installing a Ron woods full system on Monday. I was wondering what my jetting should be changed to. Currently i have a slip on white brothers that the dealer installed. What should i change my jets too?

[CRE Performance]

A pipe change isnt going to change your jetting much if any at all. The main thing that is going to change your jetting are airbox modificaitons on a 450R, they are very peculiar about airbox modifications. It may seem or sound crazy to others but one of the biggest gains I seen on my 450 was when I removed the lid completely, installed a Twin air filter, put 5 1 1/4 holes in the bottom of it and jetted accordingly.

In other words, I wouldnt change the jetting for another pipe but if your looking for more power, work on that airbox if you dont do a bunch of mud, water, or soup riding. Use what I posted above, there is a reference for both ways.

[04450rrider]

I am already running with the airbox lid removed. it is jetted for the slip on and the lid removed. So i wont need to rejet? but if i do how many sizes should i go up?

[CRE Performance]

For the lid removed on an 04-05 with a full or slip on exhaust should be 180-195 depending on your altitude along with the stock 48 pilot, 2 3/4 turns out, HRC needle on the third clip unless you are running a DynoJet Jet kit then the numbers are a little different. If its running good now, I dont thing I would go adjusting the jetting just yet, its probably not going to need it just adding a full over a slip on. If anything, you may go 1 size up from a 180 to a 185 ect. but more than likely not.

[04450rrider]

Ok thanks a ton for the information. I will be installing it tomorrow and i will she how she works!

[atb7346]

I searched for this subject and it seems like you guys are talking about the right thing. I have an '06 450r. Right now the air box lid is on and the factory pipe has the baffle and spark arrestor gutted. The bike bogs in the low end and sputters. White smoke comes out of the exhaust. Doesn't smeel like oil. I figured I am running lean. Suggestions. I plan on adding a cam, HMF pipe, air box lid removal, and K&N in the future. Suggestions. Again, it does the sputtering on take off and low throttle or hard acceleration and it is realy frustrating me. The engine noise is really load. I am not sure if it is the rocker or what. But is sounds like it is coming form the top end or the carb. HELP