2008 Yamaha 450 WR

Grretings: Have a question. Just purchased a new 2008 450 WR. I cut the throttle stop screw, but other than that, nothing has been done to the bike and I intend to keep it stock (local area is INVESTED with BLM dudes)... with this exception. I'd like to take out the "pea shooter" baffle (The smallest one in the exhaust).

Will I have to rejet my bike if I do that? If so, can somebody give me some recommendation on what I'd need to do. I ride at about 3,000 foot elevation.

Any help would be GR8LY appreciated!

Don't forget the Grey Wire

Thank you both for your time! Next question, then. One of the posts you referred me to, said if I disconnect the "gray wire" I do not have to rejet.

SO! if I take out the "pea shooter" rejet as you suggested AND disconnect the gray wire ONLY .. could I still be "green sticker" legal (at least as it "appears" to the jursidtional BLM SCMUCKS and get some certifiable "A$$holes and elbows" horsepower I hear the WR has suppressed in the bottle?

Hi, I just did all the mods yesterday on my wr 450 (2009) yesterday here in Michigan. I pulled the pea shooter, pulled out the grey wire, not cut, removed the AIS system using the Official yamaha kit, rejetted using the ais kit jets and needle except for the pilot jet and main jet which is too rich in the kit. Tusk fuel air screw at 1.5 turns and the bike runs crazy fast with no hesitation or bad spots in the throttle range. Don't forget to do the air box mod as well. You will be totally impressed, its like a new bike!!!

Green sticker no problem. Maybe leave the AIS on so you don't get harassed by some gung-ho ranger. And yeah open up the airbox too like Youser said!

Thanks everyone. Youser, want to clarify you removed ONLY the pea shooter and not both? Going to make the changes this weekend.

YAHOOOO! or rather YAMAHAOOOOOO!

Thanks everyone. Youser, want to clarify you removed ONLY the pea shooter and not both? Going to make the changes this weekend.

YAHOOOO! or rather YAMAHAOOOOOO!

You could take it a bit further than just the peashooter, and remove the entire baffle, leaving the spark arrestor in place. Even without the baffle it will be well below the 96db allowed. The muffler has a bunch of other internal "baffles" that really obstruct airflow and noise. The recommended mods are: remove the peashooter(baffle optional, but I'd recommend it), remove airbox snorkel, disconnect gray wire, cut or replace throttle stop with yz throttle stop, re-jet, and install an adjustable fuel screw. There's a thread that covers all the basic mods. Don't worry about the rangers as long as you still have the AIS installed and don't use some super loud aftermarket muffler or without a spark arrestor.

PERFECT! I rode an 07 YZ and it scared the $#!T out of me. Thought to myself' GOT TO HAVE IT"

Thanks again!

PERFECT! I rode an 07 YZ and it scared the $#!T out of me. Thought to myself' GOT TO HAVE IT"

Thanks again!

Great! With the right mods, these WR's can give you a good scare too...

Grretings: Have a question. Just purchased a new 2008 450 WR. I cut the throttle stop screw, but other than that, nothing has been done to the bike and I intend to keep it stock (local area is INVESTED with BLM dudes)... with this exception. I'd like to take out the "pea shooter" baffle (The smallest one in the exhaust).

Will I have to rejet my bike if I do that? If so, can somebody give me some recommendation on what I'd need to do. I ride at about 3,000 foot elevation.

Any help would be GR8LY appreciated!

The bike will run just fine if you're just drilling out the pea shooter. While the bike may not be "450" fast in this state of tune it'll still move pretty good. Plenty of grunt for most terrain and stealthy as heck.

With the whole baffle removed (spark arrestor in place) the bikes test 96-98 db from what I've heard. I believe the variances are more likely engine state of tune (airbox config, jetting), elevation, and sound meter calibration. I will say that the tone is kind of annoying and makes the pipe sound louder than what it is. A compromise is a PMB or GYTR performance insert. Those usually test between 92 and 94 db. Straight through exhaust like most aftermarket units or one from a YZ have a deeper mellower tone. BTW I don't recommend an uncorked stock WR can or a straight through design if you're trying to fly under the radar.

Taking the "stealth" concept further I recommend using trials tires if you're riding a closed or "sensitive" area (not that I condone such acts :thumbsup::lol: ). They conform to ground underneath you and in general cause little or no damage even under heavy throttle use (i.e digging ruts).

Thanks everyone. Your expertise and experience makes this a LOT easier!

When you say "drilling out" the peas shooter, you mean removing it, yes?

When you say "drilling out" the peas shooter, you mean removing it, yes?

yes, as in drilling out the rivets that hold it in place. Be aware that even after the rivets are removed, the peashooter might still be quite stuck inside the baffle. It might take some work to get it out, or maybe you'll be lucky and it will come right off.

Anybody have a link on "how to" remove the stock air fuel plug and replace it with an adjustable MKSR fuel screw on a 2008 Yamaha 450 WR? And am I correct that it is underneath the float bowl, yes?

A video clip would be even better! THANKS!

I read something on another forum about a leak jet and an adjustable leak jet. Could someone please tell me if I need to change it and what to change it to. Or get the adjustable one? What does the leak jet do anyway? Picking up a showroom condition 100% stock 08 WR450 next week. I Got the JD jet kit coming and plan on doing all the free mods and a exhaust. 

I read something on another forum about a leak jet and an adjustable leak jet. Could someone please tell me if I need to change it and what to change it to. Or get the adjustable one? What does the leak jet do anyway? Picking up a showroom condition 100% stock 08 WR450 next week. I Got the JD jet kit coming and plan on doing all the free mods and a exhaust. 

You are following a 3 year old thread.

 

Read the pinned posts at the top of the forum for jetting and uncorking information.

 

You do not just do jetting. You must uncork the motor, and the jet to match the uncorking.

 

The leak jet 'leaks' fuel away from the accelerator pump. The more less you leak (smaller leak jet) the bigger the apump squirt will be.

Technically is it not a jet, as it does not require the motor to be running (vacuum) to work.

 

There is no practical reason to have an adjustable leak jet, but it does come with some of the update float bowl upgrades.

Edited by TheKoolAidMadeMeSick

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