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WR450 De-Restriction and Conversion to YZ Spec Street Legal Machine

341K views 492 replies 77 participants last post by  dave ls1 
#1 · (Edited)
I recently purchased another '09 WR450 and it came completely corked up as they do from the factory. Regardless if you have a '98 WR400 or a brand new '12 fuel injected WR450, this thread will provide some helpful insight on what to do to get your machine to how it should have come from the dealership (minus the carb and jetting for the fuel injected bike(s) :lol:). I also thought that I would cover what is required to get to a "street legal" status...or pretty close anyway due to differences in laws between states. Hopefully this will shed some light on just how easy it is to get one legal and running like a true 450. I will also provide part numbers where I can. Keep in mind that these bikes are street legal machines in various other parts of the world, so most of the components and the wire harness are already set up to adapt the bike for street use and makes for a simple low cost conversion. I will also cover some other things like tire/rim sizes and chain blocks. I'm still building the bike, so this thread will be a work in progress for the next few days or so.

So to get started, here's the bike:







First things first, as soon as I got it home and out of the back of the truck I began disassembling since the bike was so choked up that it wouldn't get out of its own way.









As with any new bike, one thing that gets overlooked is the steering head bearings and the swingarm linkage. They do NOT come adequately greased, if at all, from the factory. So the first item was to break out the tub of grease and drop the forks, rear shock, and swing arm.



While I was tearing the bike down, I went ahead and removed the AIS pump and lines and installed the AIS block off plate. At this point, if you have an aluminum framed bike and are going to install a horn, the former AIS pump location is a great place to mount the horn.





After some scrubbing with a scotchbrite pad and WD40, it was time to re-assemble some of the bike:



Since I was working on the handlebars, I went ahead and installed my headlight switch:



Here's the part number and information on the headlight switch. I'm not too worried about a horn or turn signals on this bike, so a hi/low beam and kill switch is all that I am concerned with. This switch is plain, simple, and has a clean look to it:



I also installed the hydraulic brake switch:



When I get the bike the rest of the way together I plan on installing hand guards. This is why I chose to go with the "low profile" switch. It costs a little more, but also makes things a lot more simple when clearance becomes an issue.



I will also be installing a keyed ignition which I will get to later once the mail man brings it by.

So now it's time to get to the heart of the bike and what makes or breaks it...the carburetor.





The steel frame bikes offer easy access to the carb which makes jetting an easy affair. However, with the aluminum frame you have to tear half the bike apart to gain access. That being said I was reluctant to use the jets that came in the GYTR AIS kit since the main jet was a #175 which is a pretty rich main. Not wanting to have to do this twice I also ordered a JD Jetting kit as well...mosly for the needle. I will try to give a little bit of info. on why I chose the particular products that I am installing on my carb as I go along.

Included in the AIS removal kit is a shorter throttle stop. Since the cover was already off, I started with the throttle stop:



This is a picture just for a comparison:



The next step is to remove the float bowl. Once that is done, the fuel advance rod will need to be removed. I didn't take a picture of it, but it connects to the black plastic arm in the upper part of the carb by the throttle stop area and runs through the carb body down to the fuel advance side of the float bowl. You'll need a pair of basic pliers and simply pull it straight down to remove it.

Now since one of the big short comings of the FCR carb is the dreaded bog, there is a simple solution/fix to it made by R&D Racing. The name of it is the Power Pump and it is basically an adjustable leak jet. You also get another vital component to make the carb run correctly, which is a stiffer fuel advance spring. Since I was working on this part of the carb, I went ahead and installed the spring:







Now it's time to install some more appropriately sized jets. The JD kit comes with relatively detailed instructions. In my case I have just figured out which jets work best for me through lots of trial and error, blood, sweat and a lot of foul language. My elevation is about 600' so I went with a #50 pilot jet and a #170 main. Here are the respective locations of the jets:



While you're this far into the carb, it's definitely a great idea to check your float height. Per the manual, it calls for 8mm from the bottom of the carb body to the top of the float. Once again this is just some simple insurance for peace of mind:

(note that the camera angle makes the picture/float height look kinda off)


With that out of the way it's time to address the float bowl. Now the purpose of the circuit in the float bowl is to feed fuel to the fuel advance. Fuel is pulled through a check valve and is pressurized by the diaphragm which is activated by the arm which is connected to the throttle turnbuckle. Confused yet? The other part of this system is the leak jet. Now in most cases a bigger jet number would be a larger size/more fuel. In this case, the leak jet allows some fuel to bleed back into the float bowl. This means that the smaller the leak jet number/size=more fuel being advanced. To dial in a leak jet you would normally have to pull the float bowl off to make an adjustment. With the R&D adjustable leak jet you can simply make any adjustments externally with a flat blade screwdriver.

For installation of the adjustable leak jet you will need a punch and a 2mm allen wrench.





Now flip the float bowl over, it's time to install the final piece. You will want to make sure that the diaphragm spring is on and that you install the o-ring (from the bottom housing that you removed to gain access to the diaphragm) in the new adjustable leak jet.





Now you're ready to button up the bottom end of the carb and off to the needle.



You'll remove the plug from the top of the carb slide assembly.

Remember this thing that you found in the tool kit that came with your bike (if you got a tool kit with your bike lol):


Well this is what it's for:




Place the clip on the recommended slot on the appropriate needle and re-install. I also bought a R&D flex jet screw. This gives easy access to the fuel screw and also prevents it from ever falling out.

 
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33
#2 · (Edited)
Now it's time to re-install the carb onto the bike.



Install the rear shock



After that I installed the subframe and the new YZ header and exhaust:



Why YZ exhaust?

The YZ exhaust is a direct bolt on, has a larger diameter than the WR and offers a "straight through" exhaust can design (vs. the chambered restrictive WR). However, you will have to change both the header and the exhaust. There are some differences between the later model exhaust systems. The '06-'07 YZ450 header has a little smaller diameter than the'08-'09 and the exhaust can is a full size similar to the stock WR. The '08-'09 YZ450 header has a larger diameter as well as a little different profile. The exhaust can was a "shorty" design and is mostly hidden behind the number plate similar to the MX 2-stroke silencers. The later model exhaust systems will give you more top end performance, but you will sacrifice a little bottom end. You can mix and match these systems (i.e. an '06 header with a '09 exhaust can). Basically, if you have a steel frame '98-'06 you can use any '03-'05 YZ450 exhaust(s) and if you have the aluminum frame '07-'11 then you can select from '06-'09 YZ450 exhaust components. Also, I would be careful with the '08-'09 YZ450 exhaust components. Yamaha was toning down the power on the 450's during this time and the exhaust will reduce the bottom end power.



This is a stock WR header inside of a YZ ehxaust.


YZ exhaust on the left compared to a stock WR exhaust:


Stock WR exhaust:


TPS Fix:
This is the TPS plug. Every WR from the 400 to the 450 has one. The TPS is located on the left hand side of the carb and for a street application it will give you non-stop problems. If you have ridden at constant throttle, with the TPS plugged in, you'll notice a lot of cutting out and sputtering. Yamaha builds some of the best motorcycles/ATV's in the world along with musical instruments, electronics, even a super car engine, but a properly functioning TPS sensor on the FCR carb has somehow eluded them. This is a minor problem at best. Simply unplug it, secure the ends with electrical tape and tuck/zip tie the two ends out of the way. You will not harm the bike in any way by leaving this unplugged, but will definitely notice the bike running better. I have spent some time trying to adjust the TPS and the only known remedy is an aftermarket ECU.



 
#8 ·
Both the suspension and the frame make the bike stiffer and handle a lot sharper. Depending on your weight I would say that this is the best stock suspension I have experienced by far. However, in the relative future I will be sending the suspension off to be professionally set up.

I had no idea the carb work that can be done to these bikes..
There's quite a bit to a FCR carb, but when you get it dialed in to the bike there's nothing better.
 
#10 · (Edited)
The needle was all I needed from the kit. Actually I used a 170 main jet from it as well. There is also a main air jet that installs in the neck (intake side) of the carb that is only available through the GYTR kit. This is my first go round with one, so I didn't put it in my write up just yet. Basically you almost need to get both kits and mix and match lol.
 
#12 ·
Very nice write up. Would have been great to read this before my blood, sweat, and talks of burning the bike. haha. Very nice
 
#13 · (Edited)
Airbox Modification(s)

98-02 Airbox:
To de-restrict the WR400-426 simply remove the lid on top of the airbox. I believe it's 4 screws and your done.

03-06 WR450:

You can see the area behind the battery where the snorkel was at:


On the 03-06 machines behind the righthand panel on the airbox (the black portion above the number plate/side panel) there are two areas that are already outlined, you just have to cut them out.:



Though it doesn't seem like much, every bit of air that you can get to the airbox helps. After you cut these areas out, just re-install the panel and nobody will know but you.

Here is the airbox re-assembled:



07-11 WR450's:

Just a few screws. I already had the snorkel removed before I started this thread, but you get the idea.



 
#14 · (Edited)
Wheel Information

This is one topic that comes up quite frequently. All of the following information is from my first hand experience and hours of searching. I'll start with the wheel hubs. If you have a 05-up WR450, then you have a pretty nice speedometer assembly. This assembly can be re-programed depending on wheel size. However, depending on your overall tire diameter, you may need to get a speedo healer to correct the speedometer. To the best of my knowledge there are two options to retain this stock speedometer assembly. The first is to keep the stock hub and lace up a 17" rim. The second is to go to the second link listed:

Speedo Healer:
http://www.procycle.us/main/speedo_healer.htm

Rad Mfg.:
http://www.radmfg.com/Motorcycle-Hubs-Wheels-Wheel-Sets-for-MX-Dirt-Street-s/12.htm

Any YZ rims will fit, but you will lose the ability to run the stock speedometer. However a Vapor speedometer assembly will work with any rims/hubs.:
http://www.procycle.us/main/vapor.htm

WR front wheel on a YZ? You'll need this:
http://appliedrace.com/shop/index.php?main_page=product_info&cPath=32_41&products_id=1661

That being said, what wheels will fit what bike? The main difference is in the wheel bearings. Here is the best info that I have found:

http://www.thumpertalk.com/topic/546770-wheel-interchange-what-fits-what/

This is a question that gets asked often but there's never really been a comprehensive reference for the info. The info here applies to hubs from any YZ model used in a YZ400/426/450. Thanks to Bob Russell at RTR Precision Wheel Lacing for helping collect this.

Here's how it works out:

Front Wheels:

The front hub is the same from 1997 to 2001. Uses 20mm bearings. It can be identified by the four cast reinforcement ribs running across the hub.

2002 and up use the same hub. This hub also uses 20mm bearings. It is smooth across the center, with no ribs, and has a larger diameter at that point.

Early Front hubs can be used on 2002 and up by using the 2001 spacers . 2002 hub can be used on earlier bikes by using 2002 and up spacers.

This information applies to all YZ models from 125-450F.

Rear Wheels:

1998 and earlier use the same rear hub, casting number 2VN00 on the hub. Uses 20mm bearings. These will not fit 1999 and later bikes because the axle is too small.

1999 and up use the same rear hub, casting number 5ET. Use 22mm bearings. Any of these can be used in any '99-'12 model by using the spacers from the year model bike the wheel will be used in. There are four different sets of these, each matching up with a change in the swing arm. You need two for each wheel. They're the same on both sides:
1999-2001 (5ET-25383-00-00)
2002 (5NY-25383-00-00)
2003-2005 (5UN-25383-00-00)
2006-2012 (5TJ-2530S-80-00)

Use the spacers that match the year of the bike the wheel will be fit to, and any '99 or later rear wheel will work on any '99 or later YZF.

Some have asked about the fact that the drive side bearing and seal on the '06 up hubs are different than the brake side, or than the bearings on earlier hubs. The bearings are the same dimensions as the earlier hubs, however, and have no bearing (pun unintentional) on their interchangeability with other YZ rear wheels.

Bearing info for '97-up front wheels, and '99-'12 rear wheels:

Front - 6904-2RS - 20mm ID x 37mm OD x 9mm
Right Rear - 60/22-2RS - 22mm ID x 44mm OD x 12mm
Left Rear - 62/22-2RS - 22mm ID x 50mm OD x 14mm

This information applies to rear wheels from YZ and WR models. YZ fronts will fit WR's, but will not drive the odometer, and YZ spacers must be used.


Additional 17" Rim information:

The above info. will answer which wheel hubs will fit, but now the rear 17" wheel topic comes into play. Which rim is best, 4.25" or 5"? Here's the pro's and con's:

The 4.25" rear wheel is best suited with a 150 tire. This will offer a little more clearance (not too much) on the rear wheel and a little more nimble handling. This size rim will allow the use of an "o-ring" chain with a chance of minor wheel offset to gain adequate clearance. This all depends on the type/manufacturer of the rim used and overall dimensions (they all vary, trust me). You will most likely have to order your tires if you go with a 150, but once again, not that big of a deal.

The 5" rim will allow the use of a 160 tire which, though not quite as nimble as the 150, will offer a wider variety of tires available and most shops will carry 160 tires in stock. The 160 tire will offer a better contact patch in a corner, but unless you're a Pro/A class rider this won't offer much of an advantage, if any at all. Now with the additional width of the rim you will have chain clearance issues on any Yamaha, but this is not a deal breaker and can be dealt with. I will cover this problem next.

NOTE: 150 tire=4.25" rim a 160 tire=5" rim, improper rim/tire configuration will negatively effect handling and result in improper crown on the tire

Wheel/Tire Clearance:

Gaining proper rim/tire clearance is a pretty straight forward process. Here's what to expect:

1. Chain selection is the first step. Every mm will count and so a "non o-ring" chain is, in my opinion, an essential way to avoid as much contact with the tire as possible. This will require a little more maintenance/attention, but with the proper chain, it's not so bad. Just be sure to keep it clean and lubed. Make sure you pay attention to the hp rating for the chain and keep in mind that cheap chains will stretch and rapidly wear out.

2. As mentioned above, the next step is to offset the rim. Make sure that you allow tire to swingarm clearance on the side that you are offsetting to.

3. The last detail is the chain block. Thus far I have only had success with one:

http://www.gravesport.com/Chain-Block.html

(BTW, the chain is straight, it's just a weird camera angle lol)




This block will virtually eliminate any contact with the tire.

Cush Drive Hubs
Unfortunately I haven't had the opportunity to work with a cush-drive hub on any of my bikes yet. I will, however, be purchasing a set to replace my current 17's on my '09. A couple of co-workers of mine have CRF450X's and they both went with the RAD mfg. cush drive wheels. They don't have any sign of chain to tire contact and that is without a chain block. This being my first time to physically see this configuration I was definitely impressed. I try to only speak on topics that I have experience with so that I can give as accurate advice as possible.

With that being said, I would say that if you have a couple of hundred more $$$ I would highly recommend a set of these wheels. With a 4.25" rim and a 150 tire I think that would eliminated a lot of the chain slap that is experienced without a cush drive hub. However, if you are on a budget, I have not had any other issues with my WR's other than the chain hitting the tire.



Gearing
There is no magical ratio that will fit everybody's needs. Here are the ratios that have worked for me:

15/40 and 15/42: If you're gonna do a lot of highway or lots of higher sustained speed riding, either one of these ratios will allow you to comfortably cruise at 70mph at a relatively low RPM. Don't worry, you'll still have enough low end power to knock out some wheelies when you feel necessary.

14/40 and 14/42: Both of my '09 WR's have these combos. the 14/40 is still comfortable on the highway and I can still power up wheelies (on the highway) at 60+ mph. The 14/42 is on my commuter bike and I went with the 42 cause I also use the bike for dual sporting as well.

I do recommend a 14T front sprocket since these bikes do have plenty of power to spare. The rear sprocket is going to depend on your personal preference and riding style/ability. Remember, 1 tooth on the front=3 on the back. Go down one tooth on the front and that is like going up 3 teeth on the back. Go up one tooth on the front will be like going down 3 teeth on the back.

This is the front sprocket that I primarily use on all of my WR's:
 
#489 ·
This is one topic that comes up quite frequently. All of the following information is from my first hand experience and hours of searching. I'll start with the wheel hubs. If you have a 05-up WR450, then you have a pretty nice speedometer assembly. This assembly can be re-programed depending on wheel size. However, depending on your overall tire diameter, you may need to get a speedo healer to correct the speedometer. To the best of my knowledge there are two options to retain this stock speedometer assembly. The first is to keep the stock hub and lace up a 17" rim. The second is to go to the second link listed:

Speedo Healer:
http://www.procycle.us/main/speedo_healer.htm

Rad Mfg.:
http://www.radmfg.com/Motorcycle-Hubs-Wheels-Wheel-Sets-for-MX-Dirt-Street-s/12.htm

Any YZ rims will fit, but you will lose the ability to run the stock speedometer. However a Vapor speedometer assembly will work with any rims/hubs.:
http://www.procycle.us/main/vapor.htm

WR front wheel on a YZ? You'll need this:
http://appliedrace.com/shop/index.php?main_page=product_info&cPath=32_41&products_id=1661

That being said, what wheels will fit what bike? The main difference is in the wheel bearings. Here is the best info that I have found:

http://www.thumpertalk.com/topic/546770-wheel-interchange-what-fits-what/

This is a question that gets asked often but there's never really been a comprehensive reference for the info. The info here applies to hubs from any YZ model used in a YZ400/426/450. Thanks to Bob Russell at RTR Precision Wheel Lacing for helping collect this.

Here's how it works out:

Front Wheels:

The front hub is the same from 1997 to 2001. Uses 20mm bearings. It can be identified by the four cast reinforcement ribs running across the hub.

2002 and up use the same hub. This hub also uses 20mm bearings. It is smooth across the center, with no ribs, and has a larger diameter at that point.

Early Front hubs can be used on 2002 and up by using the 2001 spacers . 2002 hub can be used on earlier bikes by using 2002 and up spacers.

This information applies to all YZ models from 125-450F.

Rear Wheels:

1998 and earlier use the same rear hub, casting number 2VN00 on the hub. Uses 20mm bearings. These will not fit 1999 and later bikes because the axle is too small.

1999 and up use the same rear hub, casting number 5ET. Use 22mm bearings. Any of these can be used in any '99-'12 model by using the spacers from the year model bike the wheel will be used in. There are four different sets of these, each matching up with a change in the swing arm. You need two for each wheel. They're the same on both sides:
1999-2001 (5ET-25383-00-00)
2002 (5NY-25383-00-00)
2003-2005 (5UN-25383-00-00)
2006-2012 (5TJ-2530S-80-00)

Use the spacers that match the year of the bike the wheel will be fit to, and any '99 or later rear wheel will work on any '99 or later YZF.

Some have asked about the fact that the drive side bearing and seal on the '06 up hubs are different than the brake side, or than the bearings on earlier hubs. The bearings are the same dimensions as the earlier hubs, however, and have no bearing (pun unintentional) on their interchangeability with other YZ rear wheels.

Bearing info for '97-up front wheels, and '99-'12 rear wheels:

Front - 6904-2RS - 20mm ID x 37mm OD x 9mm
Right Rear - 60/22-2RS - 22mm ID x 44mm OD x 12mm
Left Rear - 62/22-2RS - 22mm ID x 50mm OD x 14mm

This information applies to rear wheels from YZ and WR models. YZ fronts will fit WR's, but will not drive the odometer, and YZ spacers must be used.


Additional 17" Rim information:

The above info. will answer which wheel hubs will fit, but now the rear 17" wheel topic comes into play. Which rim is best, 4.25" or 5"? Here's the pro's and con's:

The 4.25" rear wheel is best suited with a 150 tire. This will offer a little more clearance (not too much) on the rear wheel and a little more nimble handling. This size rim will allow the use of an "o-ring" chain with a chance of minor wheel offset to gain adequate clearance. This all depends on the type/manufacturer of the rim used and overall dimensions (they all vary, trust me). You will most likely have to order your tires if you go with a 150, but once again, not that big of a deal.

The 5" rim will allow the use of a 160 tire which, though not quite as nimble as the 150, will offer a wider variety of tires available and most shops will carry 160 tires in stock. The 160 tire will offer a better contact patch in a corner, but unless you're a Pro/A class rider this won't offer much of an advantage, if any at all. Now with the additional width of the rim you will have chain clearance issues on any Yamaha, but this is not a deal breaker and can be dealt with. I will cover this problem next.

NOTE: 150 tire=4.25" rim a 160 tire=5" rim, improper rim/tire configuration will negatively effect handling and result in improper crown on the tire

Wheel/Tire Clearance:

Gaining proper rim/tire clearance is a pretty straight forward process. Here's what to expect:

1. Chain selection is the first step. Every mm will count and so a "non o-ring" chain is, in my opinion, an essential way to avoid as much contact with the tire as possible. This will require a little more maintenance/attention, but with the proper chain, it's not so bad. Just be sure to keep it clean and lubed. Make sure you pay attention to the hp rating for the chain and keep in mind that cheap chains will stretch and rapidly wear out.

2. As mentioned above, the next step is to offset the rim. Make sure that you allow tire to swingarm clearance on the side that you are offsetting to.

3. The last detail is the chain block. Thus far I have only had success with one:

http://www.gravesport.com/Chain-Block.html

(BTW, the chain is straight, it's just a weird camera angle lol)




This block will virtually eliminate any contact with the tire.

Cush Drive Hubs
Unfortunately I haven't had the opportunity to work with a cush-drive hub on any of my bikes yet. I will, however, be purchasing a set to replace my current 17's on my '09. A couple of co-workers of mine have CRF450X's and they both went with the RAD mfg. cush drive wheels. They don't have any sign of chain to tire contact and that is without a chain block. This being my first time to physically see this configuration I was definitely impressed. I try to only speak on topics that I have experience with so that I can give as accurate advice as possible.

With that being said, I would say that if you have a couple of hundred more $$$ I would highly recommend a set of these wheels. With a 4.25" rim and a 150 tire I think that would eliminated a lot of the chain slap that is experienced without a cush drive hub. However, if you are on a budget, I have not had any other issues with my WR's other than the chain hitting the tire.



Gearing
There is no magical ratio that will fit everybody's needs. Here are the ratios that have worked for me:

15/40 and 15/42: If you're gonna do a lot of highway or lots of higher sustained speed riding, either one of these ratios will allow you to comfortably cruise at 70mph at a relatively low RPM. Don't worry, you'll still have enough low end power to knock out some wheelies when you feel necessary.

14/40 and 14/42: Both of my '09 WR's have these combos. the 14/40 is still comfortable on the highway and I can still power up wheelies (on the highway) at 60+ mph. The 14/42 is on my commuter bike and I went with the 42 cause I also use the bike for dual sporting as well.

I do recommend a 14T front sprocket since these bikes do have plenty of power to spare. The rear sprocket is going to depend on your personal preference and riding style/ability. Remember, 1 tooth on the front=3 on the back. Go down one tooth on the front and that is like going up 3 teeth on the back. Go up one tooth on the front will be like going down 3 teeth on the back.

This is the front sprocket that I primarily use on all of my WR's:
Hey Crash , I'm primarily interested in getting better with wheelies so with the 14/40 gearing and a stock 07wr450f would I be good to start with ? ( that way I can always slap on a 15 " front sprocket for longer frwy rides right ? ) :hmmm:
 
#22 ·
All of the 5-valve heads have titanium valves, whether it's in a R1, R6 or a WR450 etc, etc... I would say check them if it's a new or "new to you" bike, but if they are in spec. then I don't see any reason for there to be an issue. When I worked at Yamaha I think I only shimmed one or two 5 valve heads. That includes all the dirtbikes, ATV's, and sportbikes that Yamaha makes with this head design. However, if they are out of spec. shim any discrepant valves and then you might re-check them next time you change your oil. I don't think you'll have any problems though.
 
#25 ·
Awesome write up crash! :bowdown: Your bike is coming together! Did you do all this to your sumo, or is this just for your ds?

Loved the wheel write up section too. Are the calipers and rotors interchangeble as well? Or just the wheel? i.e. will a caliper from a 1999 wr400 fit a 2009 wr450? etc.
 
#28 · (Edited)
YZ Cam Installation

Now it's down to the cam. The funny thing about this is the YZ exhaust cam and the WR exhaust cam are identical (just like the intake cams). There are two things, though, that offer different performance characteristics. First of is the auto de-compression pin. The WR pin is a bit longer and has a squared off edge and the YZ has a shorter rounded off edge. This is what makes the 450's much easier to start then the 400/426. These cams will also fit the 400/426 if you don't like the starting process lol. The difference of these two pins is what makes the bike a little cold natured when you try to use the starter for the first time of the day. After the engine has fired up the starter should have no problem starting the bike. I really don't notice any difference even when the engine is cold.



The other difference is that the WR exhaust cam is advanced one tooth. What this means is that by installing this cam you are not radically changing the bike or stressing the valvetrain. This will not hurt anything and will not effect the durability or reliability of the engine. With the installation of the YZ exhaust cam you will notice a lot more throttle response, more bottom end power as well as better mid to top end performance as well.

***NOTE*** Yamaha attempted to de-tune the '08-'09YZ450. The best cam for any year WR450 is the '06 YZ450 exhaust cam (part #: 5TA-12180-10-00)

Okay, to get started you will need a 6mm and a 14mm allen socket/wrench. Remove the timing plugs and then you'll need a 17mm socket to turn the crank. Go ahead and remove the valve cover as well so that you can see the cams.





Now take the 17mm socket (you may need an extension as well) and turn the crank counter clockwise. There are two timing marks to watch out for. One looks like a "H" and the other like an "I". You'll want to line up the "I" timing mark. Now, you'll also be using the timing marks on the cams as well. All three marks have to align. The most important thing to watch out for are the two timing dots on the cam that line up with the top edge of the head. When you're top dead center (TDC) it will look like this:



Sorry about the cell phone picture quality...I'm no photographer.


The lobes of the cams should be in this position:


Next I always take a paint pen and paint the bottom dot on both cams and corresponding cam chain location. Loosely tie up the timing chain (in between the cams) with a piece of safety wire and now it's time to remove the cam chain tensioner:





Now remove the cam cap and use caution not to drop the cam bearing retainer. It fits in the forward edge of the cam cap and will come loose as you lift up on the cap. You'll have a bad day if this retainer falls in the bottom end of the engine. I would highly recommend a red rag or something being stuffed in between the cams and the head to prevent this.



Next you'll have to wiggle the exhaust cam out of the timing chain. I usually push it forward to get the bearing out of the race, pull the cam towards the intake cam and work the gear out of the chain. There is absolutely no way that I can explain this process any better lol.

Take the YZ exhaust cam and install it using the same timing dots. It will install in the same position that the WR cam was in. Ensure that the bottom dot aligns with the head the same as the intake cam should.





Now you'll re-install the cam cap and get a torque wrench ready. You will want to torque the two front bolts on the cap first (nearest the cam gear). The torque on these is 7.2 ft/lbs.



After that you will want to re-install the cam chain tensioner. To do this you will need a small screwdriver to turn the tensioner clockwise until it locks into place fully compressed.



Then install the tensioner back into the head, torque the bolts and turn the tensioner counter clockwise to release it and put tension back on the cam chain.

Now it's time to check the valve clearance. The spec. on the exhaust side is: .20-.25. I find it useful to have a set of tapered feeler gauges for checking the center intake valve. Might as well check the intake as well lol. The intake clearance(s) is/are: .10-.15. I think that the clearances are the same on all years. The feeler gauge should slide in between the cam and the shim bucket with a little resistance, but not having to force it.



If any valves are out then you'll need a shim kit in order to re-shim them to spec. I did not have any valves out of tolerance so I didn't need to do any actual shimming. The valves on the 5 valve head design engines rarely go out of spec.

After the valves are within tolerances, re-install the valve cover and you're done! I also re-installed the upper engine mounts after I routed the wire harness. I'll get some more pics of my progress tonight or tomorrow.

Now all that's left is some wiring and routing, replace the tires with a set of DOT legal ones and I'll be ready to go get an inspection sticker.

Still a bit more to go so stay tuned!
 
#402 ·
Now it's down to the cam. The funny thing about this is the YZ exhaust cam and the WR exhaust cam are identical (just like the intake cams). There are two things, though, that offer different performance characteristics. First of is the auto de-compression pin. The WR pin is a bit longer and has a squared off edge and the YZ has a shorter rounded off edge. This is what makes the 450's much easier to start then the 400/426. These cams will also fit the 400/426 if you don't like the starting process lol. The difference of these two pins is what makes the bike a little cold natured when you try to use the starter for the first time of the day. After the engine has fired up the starter should have no problem starting the bike. I really don't notice any difference even when the engine is cold.



The other difference is that the WR exhaust cam is advanced one tooth. What this means is that by installing this cam you are not radically changing the bike or stressing the valvetrain. This will not hurt anything and will not effect the durability or reliability of the engine. With the installation of the YZ exhaust cam you will notice a lot more throttle response, more bottom end power as well as better mid to top end performance as well.

***NOTE*** Yamaha attempted to de-tune the '08-'09YZ450. The best cam for any year WR450 is the '06 YZ450 exhaust cam (part #: 5TA-12180-10-00)

Okay, to get started you will need a 6mm and a 14mm allen socket/wrench. Remove the timing plugs and then you'll need a 17mm socket to turn the crank. Go ahead and remove the valve cover as well so that you can see the cams.





Now take the 17mm socket (you may need an extension as well) and turn the crank counter clockwise. There are two timing marks to watch out for. One looks like a "H" and the other like an "I". You'll want to line up the "I" timing mark. Now, you'll also be using the timing marks on the cams as well. All three marks have to align. The most important thing to watch out for are the two timing dots on the cam that line up with the top edge of the head. When you're top dead center (TDC) it will look like this:



Sorry about the cell phone picture quality...I'm no photographer.


The lobes of the cams should be in this position:


Next I always take a paint pen and paint the bottom dot on both cams and corresponding cam chain location. Loosely tie up the timing chain (in between the cams) with a piece of safety wire and now it's time to remove the cam chain tensioner:





Now remove the cam cap and use caution not to drop the cam bearing retainer. It fits in the forward edge of the cam cap and will come loose as you lift up on the cap. You'll have a bad day if this retainer falls in the bottom end of the engine. I would highly recommend a red rag or something being stuffed in between the cams and the head to prevent this.



Next you'll have to wiggle the exhaust cam out of the timing chain. I usually push it forward to get the bearing out of the race, pull the cam towards the intake cam and work the gear out of the chain. There is absolutely no way that I can explain this process any better lol.

Take the YZ exhaust cam and install it using the same timing dots. It will install in the same position that the WR cam was in. Ensure that the bottom dot aligns with the head the same as the intake cam should.





Now you'll re-install the cam cap and get a torque wrench ready. You will want to torque the two front bolts on the cap first (nearest the cam gear). The torque on these is 7.2 ft/lbs.



After that you will want to re-install the cam chain tensioner. To do this you will need a small screwdriver to turn the tensioner clockwise until it locks into place fully compressed.



Then install the tensioner back into the head, torque the bolts and turn the tensioner counter clockwise to release it and put tension back on the cam chain.

Now it's time to check the valve clearance. The spec. on the exhaust side is: .20-.25. I find it useful to have a set of tapered feeler gauges for checking the center intake valve. Might as well check the intake as well lol. The intake clearance(s) is/are: .10-.15. I think that the clearances are the same on all years. The feeler gauge should slide in between the cam and the shim bucket with a little resistance, but not having to force it.



If any valves are out then you'll need a shim kit in order to re-shim them to spec. I did not have any valves out of tolerance so I didn't need to do any actual shimming. The valves on the 5 valve head design engines rarely go out of spec.

After the valves are within tolerances, re-install the valve cover and you're done! I also re-installed the upper engine mounts after I routed the wire harness. I'll get some more pics of my progress tonight or tomorrow.

Now all that's left is some wiring and routing, replace the tires with a set of DOT legal ones and I'll be ready to go get an inspection sticker.

Still a bit more to go so stay tuned!
Ok, I have been researching this, but may have missed it. I have an 05 WR450, if I retard my stock cam one tooth will I have problems with e-start? Can I machine down the decompression pin so it is proper height? My good friend is a machininst, so this wouldn't be a problem at all. Although he has retarded many wr cams without machining the decomp pin and said they had no problems starting. Thanks.
 
#29 ·
Wow this needs stickied immediately this is an awesome thread full of information and write ups. One question though. I noticed you unplugged your tps on the 09. Does my 03 wr450f have one?
 
#34 ·
Test ride went great! The best way to put it is: I'm gonna have to tear my sumo back apart and re-do it like I did this dual sport. Much more power, more solid feel, this bike is top notch for sure. Pics are uploading and as soon as they are finished I'll get this thread updated. Got some good stuff to finish up with! This has been one of the most straight forward builds that I have done. Mostly cause the bike was bone stock when I got it :lol:
 
#35 · (Edited)
Wiring

Okay, down to the last part. This is the most important part of getting the WR street legal. A lot of the information covered in this thread doesn't do much in the way of getting the bike "legal" for road use. Like I mentioned earlier, these bikes are street legal machines in certain parts of the world. What this means is the harness is already set up, you just need to connect a couple of wires. One other thing that I will mention. I am in no way an electrician. I understand the basics of wiring, but I'm no expert by any stretch of the imagination. I'm sure that there are other ways to wire these bikes and if anybody has any pointers or suggestions I would definitely like to hear them. Well, here's the fun part...making the bike light up:

WR400/426
If you want to add a key switch then you will need a kill switch activated key switch (picture is for reference...I know it looks the same lol):

This switch will wire/tap into the kill switch wiring.

You'll need a ballast with the additional plug for the headlight bulb (available at any auto parts store):


On my 426 there was a blue wire that I used for power (Not sure if that's for all the 400/426 bikes or not). Most likely it was the stock power wire for the headlight. I ran that to my headlight switch and then the headlight switch wires went to their respective headlight plug locations. The brake switch is going to pick up the blue wire for power (off of the taillight harness) and the other wire will connect/splice to the yellow wire.

03+ WR450
First off, I highly discourage cutting ANY wires. Leaving the harness intact can save you a headache down the road and will preserve the value of the bike as well. Any pins that are backed out of a plug I simpy electrical tape the metal connector/pin and zip tie them together to keep the tape secure. To un-pin a connector just get a pick or a small flat blade screwdriver and lift the plastic retainer and pull the wire from the back of the connector (the wire should pull right out of the plug):


To get started, I will start with the ignition switch. I ordered the Baja Designs key switch from Motostrano (part #: 05-9168)


Seems like no matter what they have pictured, you always get something different (this has happened with all key switches and all vendors in my experience). However in this case it worked out even better because the ignition came with the plug that fits the harness plug on the bike. A simple continuity check and re-pin of the connector and it was a plug and play install...so far so good! So in order to have a key ignition, you will have to remove the on/off switch:


Now don't throw this switch in the trash just yet. You will need to re-use the bracket that the switch is mounted to (the headlight assembly attaches to it). I cut the bracket down to just the part that the headlight assembly attaches to because you'll need that space for the key switch.


Here's the key switch:


and like I mentioned before I needed to re-pin/re-locate one of the connectors. I left the other two un-pinned since they are not needed.


Now this only applies to the '03+ WR's. You will start with a 4 pin plug. You will use the red wire and the brown wire to establish your electrical connection. The other two wires in the plug are for the led indicator light...those will no longer be necessary and can be taped up and tucked away. If you have a key switch that will utilize your original harness plug, ensure that the two pins that give you continuity (when the key is in the "on" position) are pinned in the same location as the red wire and brown wire on the bike's harness.

As pictured above, I mounted the key switch bracket with the hole that is located on the upper right hand side of the speedometer assembly bracket.

A simple ops check confirms that the bike now has electrical power:


After that I wanted to establish power to my headlight and kill switch assembly. Since the headlight switch came pre-wired, it was almost as simple as plugging everything together...but there was some assembly required lol.

First off, I routed the "power wire" from the switch to the power wire from the key switch.


and from there, after I crimped the plug ends onto the harness coming from the headlight, I connected the headlight wires together. Using a headlight switch will cancel out the stock headlight plug coming from the bike harness (green wire and a black wire). However the ground wire can/will still be used for the new headlight switch.



Once that step is complete you can turn the key to the "on" position and check the function of the headlight.

Next up is the kill switch. I took the kill switch and cut the wires a few inches above the plug (since I won't be using the stock kill switch). Then I spliced the wires from the new headlight/kill swich to the plug and plugged it back in to the bike.

That completes the ignition/key switch and headlight/kill switch installation.

Now it's time to wire the brake switch. This is a simple switch and so is the wiring. One wire will act as the power wire and the other will connect to the yellow wire on the tail/brakelight harness. For this I was able to use the wire connectors that came with the keyswitch. Just a heads up, I would not recommend hard wiring the brake light straight to the battery because it will drain the battery.

With that being said, I tapped into a power wire from the starting relay. This wire is blue with a white stripe and will ensure that there is no power going to the brake light when the key is turned off.

This is the "power" wire:


This is the "actuating" wire (located behind the left hand side panel/number plate):


After that just route the wires back up to the wires coming from the switch:


Crimp/connect the wires:


Do NOT forget to bleed the front brake after the switch installation!
...and you're done! Make sure to properly tape up and secure your connections. Now there's just one more thing to do to complete the de-restriction.

Located behind the left hand side panel/number plate are three plugs/connectors. Locate the one that has a red with black stripe wire and a blue with white stripe wire with the grey wire in the middle.

The grey wire will not have any other colored stripes or markings. Simply un-pin this wire and tape/secure it.

Sorry for the picture quality:


And now you're done:


Enjoy the test ride!
 
#36 ·
Excellent!


Only things I did just a little differently on my '04 WR was I left my "on/off button" on the bike and plugged in and wired in my baja designs key switch in with the killswitch button circuit wiring and then removed the kill switch button from the handlebars. I think your way looks a little cleaner but it all still works about the same. :thumbup:

Also, rather than buying the ballast with an additional plug (didn't even know those existed. lol), We ran a new connector pin and wire through the empty ballast slot in the stock headlight and connected that with the control switch. We just had to pick out the right connection pin that would fit and match the other two pins in that stock ballast piece.

For my horn, I ran a wire directly to the battery terminal and grounded the horn on the botton headlight mounting bracket that connects to the lower triple so the horn is live all the time. Helped avoid cutting into anymore wires for power.

Lastly, I don't know if it was necessary or not, but I also ran an in-line fuse with the rear brake pressure switch.

Definately was a fun learning curve for me. :D
 
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