2006 Yamaha WR 450f Performance Mods?

[Yamahondaha]

Pardon my newbie questions, but I am new to dirt bikes, I have experience with cars and gas R.C. cars, so I'm not totally ignorant.

Would just doing the airbox mods be worth it?

I'd rather not do the AIS removal because it's not legal here in California, except for closed course competition.

What about the grey wire removal and YZ throttle stop mods, would they accomplish anything if I don't do the AIS removal?

I did all the Mods but left the AIS on because I made mine street legal and didn't want anyone to blow the whistle on my emissions. The AIS just lets air into the exhaust to completely burn any leftover fuel and has no effect on performance. Now that I am through the DMV and have a plate I might take it off to save weight. I will keep it in a box and put it back on if I hear they are cracking down on emissions. I took off all the smog stuff from my DRZ400S and my Husqvarna TE510 and no one has ever looked for the emissions stuff. The only things that are being checked now in CA are spark arrestors and 96 bdl sound level, no one checks for emissions equipment (not yet).

[MadAboutWR450]

Is there a kit for cutting open the right side of the airbox? Is it left open/exposed, or is there some kind of foam screen to add?

[Matty05]

Is there a kit for cutting open the right side of the airbox? Is it left open/exposed, or is there some kind of foam screen to add?

No kit needed mate, just take off the black cover (1 or 2 phillips head screws from memory) and cut away the indentations.

put the cover back and it is protected from the elements.

look at www.thumperfaq.com for this free mod and others too.

[red7]

This is a great thread! I just got an 04 WR450 and like everyone else, was underimpressed with it's performance.

DO all of these mods go for the 2004 as well? Performance wise, how much better is the GYTR compared to the PMB exhaust? I want something that sounds a little throatier but not too loud. Someone made a comment that the GYTR was quite loud. Is there a happy medium where I can get something that performs just as well and is louder than stock but that doesn't sound like a 2-stroker? Money isn't a huge issue as long as it's under $500 for the exhaust. Do I want a slip on or a full system? Thanks!

[Matty05]

Red7, all of the free mods work on the '04's.

The PMB insert is not going to make any where near the power of a performance pipe. It is only a tip.

You have to ask yourself a few questions first before purchasing an exhaust. The first one is "where do I want the power?" There is supercross and motocross versions of many race pipes. The supercross pipes have long headers which make huge torque, power in the low to mid range. The motocross versions have power in the mid to top end range. If you ride heaps of tight single track, go the supercross version. If the more open space is your thing, go the motocross version.

The second question is "how loud do you want to go?" By the sounds of it, you want a "FIM" (what the AMA is to the europeans) pipe. They are limited to 98db. White Brothers make their aluminium and carbon pro pipes in 98db euro versions. The GYTR pipes are truely awesome, but yes, they are loud. They are over 100db, but quieter than my Procircuit Ti GP system. There is also a big following for the FMF Ti powercore slip-on muffler here, but IMO they are not built strong at all. They too are over 100db.

I have a 98db GYTR "propower" slip-on muffler on the WR250, but the problem is you guy's don't get this pipe in the states. Trust me when I say it would be perfect for you. The sound is grunty but noise is very tolerable. My procircuit can be a bit annoying at times in comparison.

The third is "slip-on muffler or full system?" The reality is you only need a slip-on muffler. The WR's and YZ's use the same header. Performance pipes use different header to get better gains, but cost lots. The Dr D systems are excelent chouce for full system at bargain price. They work awesome too. For the best bargain, get an '05 YZ450F muffler off ebay or buy off someone here. It adds a few more ponies and can be brought for about $50.

[red7]

Thanks Matty!

I'll be riding more open areas, mainly beaches down in Mazatlan. Speaking of beaches, is there a specific material that I want to avoid due to higher likely hood of rust from the salt in the air?

I definitely don't want it too loud. No sound issues down in Mexico or really even here in Arizona but I have lots of friends in California so I'll be doing some riding over there as well. I do want it louder and especially throatier/deeper than the stock one though so I don't want it too quiet. How loud is the YZ muffler compared to stock? I guess I want something in the medium volume range....not like your procircuit but not stock either.

So I can't order the GYTR propower muffler in the states? That sucks! Are you still thinking the YZ is the way to go for my scenario?

Thanks for your help!

[jumbo12]

The most important mod you can do is to install a Boysen "quick shot" accelerator pump cover. This completely eliminates the slow throttle response in the WR's from 04 to present. It makes the WR a different bike all together.

Ryan

Colorado

[MadAboutWR450]

Do you happen to know where I can get more information about the air box modification? Are there any illustrations/instructions on TT? Thanks.

[Yamahondaha]

Do you happen to know where I can get more information about the air box modification? Are there any illustrations/instructions on TT? Thanks.

No need for instructions just rip out the snorkel top rear and cut out the two holes on the kick start side of the air box (remove the black cover and you will see the precut holes) Just remember to open up the exhaust and go bigger on the carb jets (you might need instructions for that)

I just did the AIS removal and like the cleaner no popping deceleration...

[Matty05]

Thanks Matty!

I'll be riding more open areas, mainly beaches down in Mazatlan. Speaking of beaches, is there a specific material that I want to avoid due to higher likely hood of rust from the salt in the air?

Just wash your bike real good and spray everything with WD40.

I definitely don't want it too loud. No sound issues down in Mexico or really even here in Arizona but I have lots of friends in California so I'll be doing some riding over there as well. I do want it louder and especially throatier/deeper than the stock one though so I don't want it too quiet. How loud is the YZ muffler compared to stock? I guess I want something in the medium volume range....not like your procircuit but not stock either.

So I can't order the GYTR propower muffler in the states? That sucks! Are you still thinking the YZ is the way to go for my scenario?

Thanks for your help!

Right. Have you tried the stock muffler with the pea shooter end tip pulled out completely? A YZ muffler is about the same volume. Still quieter than my Procircuit, but louder than 98db. It adds just a bit more power, but not much, still noticable. If you can get hold of one real cheap, go for it.

If I brought a new pipe tommorrow, it would definately be a White bro's aluminium pro 98db "euro" version for sure. That is just me. Real nice, not whimpy sound, not ear splitter either. Just right! If you ride cali now and again, just put in the white bro's E2 tip in and it will be even quieter.

[Spentor]

I just purchased the AIS removal kit (GYT-5TJ93-69-00) today. All I have to say is "is there an ais removal kit for dummies"

I imagine the average mechanic can navigate through the instructions and successfully make these mods; unfortunately, I am already stumped with the first phase...

I do know what end of the wrench to use and it stops there

[Spentor]

After 24 hours of proving to myself what a horrible mechanic I am; alas, I finally completed the ais removal project, removed gray wire, baffle, new pilot jet, cut holes in air box and replaced the wr throttle stop with the YZ. I can not stress enough what a significant increase in power and performance the $40.00 ais removal kit was.

It is almost sad considering how many new WR owners are out there riding their bikes to about 70% of it's potential....

[Matty05]

It is almost sad considering how many new WR owners are out there riding their bikes to about 70% of it's potential....

Put a race pipe on your bike and you would know what 70% really was!

You are at 70% now!!!

[MojaveThumper]

Put a race pipe on your bike and you would know what 70% really was!

You are at 70% now!!!

Just did this mod as well and WOW what a difference. Can't believe there is even more to get out of this bike.

[airhose]

OK, I need a summary!! I am currently sitting here in Iraq (another 47 days to go!!) and I am getting things in order for the arrival of my '06 WR450F. Actually the bike is waiting for me... whaterver, that's a different story. I am going through these threads and getting confused by all of the different combinations of mods. I want to ride the bike once in stock trim, but then it's time start moving up. I plan to open up the airbox, remove the exhaust baffle, swap throttle stop screws, and discombobulate the grey wire. I will add the zip-ty fuel screw and remove the AIS as well. I am doing pretty good up to this point, but it starts getting "grey" from here on out. BIG question: do the AIS removal kits (TT or GYT-R) INCLUDE jets, adjustable needle, and instructions? I will be riding in Wisconsin with temps being from 40 to 90. I am hoping that I can re-jet once and then be done with it because I WILL eventually drive myself nuts or wear out the screws on the carb.!

could someone please tell me WHAT is in the TT AIS removal kit?

And last, but not least, WHICH Zip-Ty fuel screw do I need for the 2006 WR450F. Please be nice since I am not able to actually touch or look at my bike for a while... all I have are pictures and YOU!

Thanks,

Scott

'00 KTM LC4 400 SXC

'06 WR450F

[airhose]

Doboth the GYT-R and TT AIS removal kits contain the same parts?? GYT-R has some jets and a needle... how about the TT kit?

[Matty05]

Doboth the GYT-R and TT AIS removal kits contain the same parts?? GYT-R has some jets and a needle... how about the TT kit?

No, just the plugs I believe.

[Matty05]

Ok Scott, I would be getting the GYT-R AIS kit to start with mate, as it comes with 48 pilot (this is correct size for 99% of people) and adjustable needle as well as the block off plugs.

The Zip-ty fuel screw you will need is "FSM01" http://www.ziptyracing.com/products/product_detail.aspx?id=MTEwMQ==

How do you feel about jetting??? This is everything you need in the one kit:

http://www.ziptyracing.com/products/product_detail.aspx?id=MTEwOA==

Definately the best if you could handle the pain of jetting.

[airhose]

Well, so far I have ordered the following:

TT AIS removal kit (will return if not same as GYT-R kit for = $$)

TT FSM01 (Storm equivalent)

PMB quiet insert

Works Connection radiator braces (I'll be using those ALOT!)

Moose brush-guards (see radiator braces)

Dirt skinz

I plan on riding it stock at least once for break-in and familiarization, then I will:

Disconnect grey wire

Make blood squirt out of finger that I just stabbed while disconnecting wire

Remove AIS

Install jet and needle from AIS kit

Swear

Install Storm fuel screw

Swear some more

Open up airbox

Apologize to wide-eyed neighbor lady who heard the ruckus

MPB exhaust insert

YZ throttle stop screw from AIS kit

Knock bike off of workstand while tripping over the damned dog

Call it a night after burying the dog.

Does that sound about right?

[pHreaC]

Why not: put the dog in the freezer and eat it later?