Need advice on mod/upgrades on my 05 wr450

[rEVOLution2012]

Hey all, first post for me but have been pouring over this site for few days now. I recently baught an 05wr450 and love it, but I really wan't to uncork it I ride trails mostly in AZ desert. It sounds like these are a must.

Yamaha GYT-R AIS Removal Kit, P/N GYT-5TJ93-69-00

1.) Removed the grey-wire

2.) Add an adjustable Fuel Screw

3.) Add a MJ 168 and 48 PJ( or w/e is recommended)

4.) Add a throttle stop screw

5.) Add a exchaust insert or remove baffle

6.) Open the air box openings

I don't have the means or ability to do all these myself so I want to have it done professionally. Any estimate on how much this is goin to cost? also is it best to take it to a yamaha dealer or is it something any reputable shop will do? I don't know enough about these bikes to do myself. Do I have to have it rejetted afterwards?

[wrdr-rider]

When I bought my WR, I was a little overwhelmed with what looked like a very complicated list of mods to uncork it - with really no mechanical experience. I would recommend trying to tackle your list yourself. Take your time and print out the steps/pics (they are well documented on here and thumperfaq). You can always 1) do additional research 2) go back to stock or 3) ask any questions that you may run into. Its really not that bad, plus you'll have a much better understanding of your bike and spend a mere fraction of having someone else do it.

[miweber929]

Hey all, first post for me but have been pouring over this site for few days now. I recently baught an 05wr450 and love it, but I really wan't to uncork it I ride trails mostly in AZ desert. It sounds like these are a must.

Yamaha GYT-R AIS Removal Kit, P/N GYT-5TJ93-69-00

1.) Removed the grey-wire

2.) Add an adjustable Fuel Screw

3.) Add a MJ 168 and 48 PJ( or w/e is recommended)

4.) Add a throttle stop screw

5.) Add a exchaust insert or remove baffle

6.) Open the air box openings

I don't have the means or ability to do all these myself so I want to have it done professionally. Any estimate on how much this is goin to cost? also is it best to take it to a yamaha dealer or is it something any reputable shop will do? I don't know enough about these bikes to do myself. Do I have to have it rejetted afterwards?

You're getting WAY ahead of yourself here. stop spending so much time reading and more time riding!!!!

First off, how do you know most of this stuff hadn't been done if you just bought it?

Second, NONE of these are truely "musts", especially the AIS block off kit and adjustable fuel screw.

Third, and no offence meant, I'm not 100% sure you know what most are any of this stuff you listed is as you already mentioned rejetting it, #3, and are later asking if you need to rejet. Be sure what you need to do and not what you read to do.

It's a pretty potent bike stock, but with a VERY easy hour or so can be made even better. READ THE STICKYS AND YOU WILL HAVE STEP BY STEP INSTRUCTIONS ON HOW TO DO EVERYTHING!!!! It's not hard and a $20 set of tools will get you through anything you need to do. What will you do in the desert when you have a breakdown if you have zero knowledge of your bike?

Jetting I get having done professionally because it can be tricky to get right but there are a ton of charts on this website (and tge JD kits come with them as well) to get it right almost the first time.

"Needs":

Grey wire snipped

Throttle stop shortening

Airbox plug removed (if there is one)

Exhaust plug removal and/or insert install

Rejet according to mods and elevation if needed!!

Enjoy the bike before running out and modding willy nilly. A lot of people find it quite enjoyable stock for some time unless they've been racing 450's for a while. Figure a shop to take 2 to 3 hours to do the above, they are not quick about doing non-factory mods.

I'd be surprised if most or all the mods weren't done already, however.

Welcome!!!

Mike

[Leardriver]

Make friends with a TT'er who has done these things and can help you. You can make the bike run a lot better in under an hour.

[HighRevz]

What about the "leak jet"? sorry gents but....what is that???

[Just_a_trail_rider]

Hey all, first post for me but have been pouring over this site for few days now. I recently baught an 05wr450 and love it, but I really wan't to uncork it I ride trails mostly in AZ desert. It sounds like these are a must.

Yamaha GYT-R AIS Removal Kit, P/N GYT-5TJ93-69-00

1.) Removed the grey-wire

2.) Add an adjustable Fuel Screw

3.) Add a MJ 168 and 48 PJ( or w/e is recommended)

4.) Add a throttle stop screw

5.) Add a exchaust insert or remove baffle

6.) Open the air box openings

I don't have the means or ability to do all these myself so I want to have it done professionally. Any estimate on how much this is goin to cost? also is it best to take it to a yamaha dealer or is it something any reputable shop will do? I don't know enough about these bikes to do myself. Do I have to have it rejetted afterwards?

doing these things will take just a little more skill than typing into Thumpertalk.

try it first. These are really simple things to do.

If you are going to own a trail bike and eventually take it out on the trail, you are going to have to know some basic things about your bike. This is where you start learning.

come back to Thumpertalk for help and you'll get plenty. These are very simple things to do.

[cherrypicker7]

The one thing you don't want to do is to try and remove a baffle in the stock exhaust. I just went through the process, actually stopped midway, because it wasn't what I'd expected. I'd definately remove the small "pea shooter" exhaust and do the other mods, but I'd stay away from trying to tear apart that exhaust. Not sure at this point whether I'll put it back together or just sping for an aftermarket.

[pennell17]

well revolution 2012 this is also my first post on TT. I have owned a 2004 wr450fs for 2 years now that i managed to get street legal..... I have done all the free mods ie:

grey wire cut, opened air box, un corked exhaust, re jetted (which info is no good to you, due to the fact i live in damp cold conditions at sea level)

recently i followed a previous post on TT and hard wired my accelerator pump lever to the enguagement lever (rather than spring delayed action) and droped the leak jet one size, and boom, this was the most noticeable increase after all the other mods were done. Made the throttle response hit like a brick and cleaned up the throttle chop bog without all the painfull squirt timing and duration.

I hope this info helps and thanks to all you guys that posted on this site and made my wr truely a weapon not a toy all info on these bikes is very appreciated

[rEVOLution2012]

Thanks for your time guys! I do appreciate it. I do have a couple more questions regarding the mods listed above.

#1 Do you recommend ordering parts online? if so which site is good and reliable?

or is it about the same as buying from the shop?

#2 Do I have to research what size jets will be needed after the mod, or is that something a shop will use the dyno to figure out the best sizing.

thanks!

[cherrypicker7]

Depends upon what kind of parts you are talking about. Some stuff you have to get directly from Yamaha, Rocky Mountain ATV/MC gets a lot of my business. Price has a lot to do with it, if you order enough, shipping is thrown in and that is becoming more of a big deal. They have some excellent instructional videos you may want to look at, and sometimes you can also find them on Youtube. There is a jettng tutortial on the website with some recommendations as well.

[pennell17]

Hey fellas here is my 2 cents

In my opinion wich may be a relevant to you as shuvving balogna in your carb. I reccomend you do the plug test to justify whether you need a bigger main etc. Charts are good for a basis to start but to get her perfect and sleep at night knowing your not gonna nuke a piston, crack your head or weld her togeather id take the pain of checking personally.

1) Put a new plug in your bike and lets check main jet size by trying to avoid any ideling and run her as close to wide as you can for a few miles. Then hit the kill switch and pull the plug and check color if she is white go with a bigger main jet if she is black as moby's arse underwater go with a smaller main. Goldish brown is good.

2) Next new plug or clean the crap off the old one and check needle height by running her between 1/4 and 1/2 throttle steady again avoid prolonged ideling and hard accelerations. Repeat the proceedure to check the plug. If she is white raise the needle by lowering the clip, if REALY black than lower the needle by raising the clip one notch.

3) If your bike is ok to start and idels fine you may not need to frig with the pilot jet, keep in mind that the air screw should be set to spec check on how many turns i cant remember i think it is 1-1/4 turns from bottomed out in correct me if im wrong. If it is still a bugger to start with the choke on and you find yourself cracking the trottle to get a stutter out of it try goin one bigger on the pilot jet.

4) last but not least you may find that lowering your leak jet size one will make some of your mid to low bog diminish. The leak jet from factory is made for being almost wide open all the time if you ride woods this wont happen. I run woods and track and fire roads with my leak jet dropped one and accelerator pump hard wired to the eng lever and i love it no noticeable loss of scream up top. This mod was covered on TT before you should be able to find it. Note wr's have a FCR flat carb.

Another opinion of mine, is dont waste your money on the quick shot 1,2 or 3 they have an adjustable leek jet and on mine kept on moving around not reliable work great but when they move holly gutless hard to diagnose.

I have ordered some parts from motorcyclesuperstore.com and they seem to be alright big selection alot of sales but prices dont differ much from TT store.

Remember any mods to the air box and exhaust need to be done before the plug test or your gonna have a long weekend. Best of luck bud have fun with the old FCR carb surgery finicky little buggers but when they work they work very nice.

Thanks again for all the help from you fellow TTers

[rEVOLution2012]

I've found a lot of improvement with a few simple mods, now it seems im just experimenting more or less. I live in AZ so I am in all sorts of different terrain but my WR champions everything I put in front of it lol. I am having some issues with overheating now that it's getting 100+ degrees so no putting around=) This site has been a huge help no matter what it is I seem to find it here somewhere. Really glad to have the more experienced riders & mechanics here to explain if I need it you guys kickass

[rEVOLution2012]

I've found a lot of improvement with a few simple mods, now it seems im just experimenting more or less. I live in AZ so I am in all sorts of different terrain but my WR champions everything I put in front of it lol. I am having some issues with overheating now that it's getting 100+ degrees so no putting around=) This site has been a huge help no matter what it is I seem to find it here somewhere. Really glad to have the more experienced riders & mechanics here to explain if I need it you guys kickass

[Just_a_trail_rider]

I've found a lot of improvement with a few simple mods, now it seems im just experimenting more or less. I live in AZ so I am in all sorts of different terrain but my WR champions everything I put in front of it lol. I am having some issues with overheating now that it's getting 100+ degrees so no putting around=) This site has been a huge help no matter what it is I seem to find it here somewhere. Really glad to have the more experienced riders & mechanics here to explain if I need it you guys kickass

It should not overheat if you are moving. Check your jetting. is it lean?

You need to run a quality coolant. Some people like engine ice, but I always run the same stuff I put in my car, which is a quality coolant. I do have to top it off every hundred miles or so, but no overheating, even in technical terrain.

[MY-BLUE-BEAST]

The mods are very simple to do, and does not requier a whole lot of experience except for the carb. Most if not all of these mods will already be done if it is used and the other guy new about them. If you need pictures for any of these let me know and i can get you some.

1) The grey wire is located under the gas tank in a bundle of six wires, there are two sets of wires, but the grey is easy to find. Do not cut the wire, unplug it from the base to try it first. What i did is i put the wire on a toggle to switch between the different ignition mappings, and it is noticable when you switch it.

2) The air box is easy as well, take the seat off and locate the snorkle behind the batery. To cut this out take a utility knife and cut right down the middle brace, a saw works to. Just doing this doesnt open it up a whole lot, so the next step is to widen the hole. you will notice a raised line around the hole, cut along this to widen it. Next take the right side panel off, the black panel next to it comes off with two screws, easy to see. If the wholes are not already there, follow the raised out lines that are there, just the two, they are very noticable.

3) The throttle stop is easy to, it is located on the right of the carberator behind the throttle cover, if it is short it will be noticeable, if not you can either cut off the extra which is 11mm, cut that off and smooth the edges with a file or buffer wheel, and replace the the stop.

4) Since there is a lot of water in my area, I moved my carb breather tubes from the bottom of the bike to the top of the airbox under the seat along with the cam breather. This is recomended if you do a lot of river crossing.

5) The exhaust baffle is simple, for your 2005 you will have to remove the end cap, the "spout" off the end has a bolt on the underside of it, remove this, but hold onto the baffle as you do it so it doesnt drop, and simply remove it and you are good to go.

6) Now comes the fun part, the re-jet. This is easy once you figure it out. A universal jetting that is good for practicaly any elevation that i put in my bike is this

Main: 165

Pilot: 45

Air Boot: 72

Leak: 40

Pilot Air: 100

E-clip: second from bottom

Fuel mixture screw 3 turns out (this will vary in different elevations)

If your exhaust pops on deceleration after this, take the fuel screw out an extra 1/4 turn until poping stops

I will be happy to post pictures of this procedure if you need it.

7) The AIS is just another EPA regulation put on the WR after the California Red sticker of the 2004s, it is located on the right of the bike. look it up to see what it looks like, but it is most likley gone. If it is there, buy a removal kit and follow the directions, it is that simple

These mods will open the bike up and give you a great boost.

Prices of these mods are free except for the new jets, which comes out to about $30

For procedures, visit www.thumperfaq.com, this site is based on the WR250Fs and YZ250Fs, but it works just the same for the 450s. Also ask for pictures and I will post them. Have fun, and dont try it if you think you cant do it, you dont want to ruin your bike.? But other wise, try it out and i promise you wont be dissapointed.

[Just_a_trail_rider]

2) The air box is easy as well, take the seat off and locate the snorkle behind the batery. To cut this out take a utility knife and cut right down the middle brace, a saw works to. Just doing this doesnt open it up a whole lot, so the next step is to widen the hole. you will notice a raised line around the hole, cut along this to widen it. Next take the right side panel off, the black panel next to it comes off with two screws, easy to see. If the wholes are not already there, follow the raised out lines that are there, just the two, they are very noticable.

All great advice. but... if you routinely go through deep water crossings, do not cut holes in the side of your air box. You will dump water right into the airbox when it reaches the level of the cutout. I have long since closed up those holes in the side of the airbox. You'll be fine with air until you are holding the throttle wide open , which is something most of us rarely do, especially offroad.

[Salinas_THumper]

I look for all of my parts on Ebay normally and usually can find great deals there. I f they dont have what im looking for the I will go to http://www.chaparral-racing.com/home.aspx or rocky mountainmc.com. hope that helps

[MY-BLUE-BEAST]

All great advice. but... if you routinely go through deep water crossings, do not cut holes in the side of your air box. You will dump water right into the airbox when it reaches the level of the cutout. I have long since closed up those holes in the side of the airbox. You'll be fine with air until you are holding the throttle wide open , which is something most of us rarely do, especially offroad.

Water really wont get up into the airbox through the holes, they are a good 2 1/2 feet+ off the ground even with someone on the bike and they have that panel in the way. And if you go through water it will V away from the bike and not even come cose to the holes. If you sink it sure, but then you are screwed any way. But yeah I did it and all I ever do is river cross. No problems yet.