My 2002 WR426 Project (In bits)

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Are you putting motard wheel on? Mine had been ridden on the road. I believe that's what destroyed my gearbox. Without a cush drive it's just too much stress on the box. Back cutting them will help.
 
Could you please measure up the depth of the new timing gear teeth on your new crank please If you get a chance? I'd like to compare to mine... I'm a bit worried mine are a bit worn as well.
 
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i got 1.45mm on my new crank sprocket approx same location
And i got 1mm on my old sprocket i was not willing to use..

if they start bending back or look out of form time to replace. it will also affect camchain life greatly.
 
I had to replace my swingarm linkage bearings (and shock bearings and seals as was included with the kit)
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The hardest part about this is getting the old bearing carriers out..
I resorted to using my die grinder to cut a line down them to release the pressure

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Anyway installation went smoothly enough.. ENSURE YOU START TRUE.. then the rest is easy

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4 bearings later.. and seals.. Looking good

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I am putting the build on hold for a little while as because i am busy studying so $ is tight.
I need to order the correct shaft for the transmission and the actual swingarm bearings and bushings etc.
And then get my tank and seat combo also but i want to hear this baby run first.
 

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Here is mine image.jpgimage.jpg
Did you get my inbox?
Re tooth depth is that 14.5mm ?
 
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I have a linkage I need to install on my 125 so it's good to see how to do it :)
 
I need to replace a cracked valve guide and a seat will need to be recut as it's messed up a little or replaced pending how much meat is left. I replaced the tchain a month ago.
I have inboxed again...
 
It has a diffenent tank and rad cowls as well ... It's frame and motor is 2001 wr
Alloy subframe and side covers etc I know it's later but not certain what it is? If you say 2005 it prob is I'm not that familiar with the differences between years
 
rileyp said:
It has a diffenent tank and rad cowls as well ... It's frame and motor is 2001 wr
Alloy subframe and side covers etc I know it's later but not certain what it is? If you say 2005 it prob is I'm not that familiar with the differences between years
Click to expand...
Its from a 2005 wr 450 or 04.. along with the seat, rear fenders and tank etc..
The differences between my motor and your motor is mine has titanium valves and yours has steel valves.
Also the clutch side primary gear has a keyway like a flywheel whereas my 426 has a one smaller spline to align to.

Also the bigger end on the crank is larger and the piston is a little larger
 
Mine has titanium valves .... I anodised one the other night to prove it wasn't stainless!
White sparks off the grinder as well . My pinion gear is splined as well. It's a 426
The 400 had steel valves. The 400 and 426 have the same pinion gear .5JG-16111-00-00 GEAR, PRIMARY DRIV $42.89
 
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The balancer gear and shaft are the same on the 400 and 426
5BE-11455-00-00 SHAFT 1 $154.16

5BE-11531-00-00 GEAR, BALANCE WT $84.47

For your info (you may already know this of course) it is possible on a 400 to use a 426 barrel and a 450 piston and a 400 or the 426 head To upgrade a 400 to 426cc as the 400 and 450 both have a 18mm gudgeon and the 450 and 426 have the same bore size.
The 426 has a 19mm gudgeon though so it's pistons can only be used on a 426 rod.
Info on it is here 400 to 426 conversion, the easy way - YZ 400/426/450 - ThumperTalk
 
Have a look at the diagrams again, i was scratching my head the 1st time.. lol
I have both types of cranks i assume the person before me was smart and bought a wr400 crank.
 
Okay, Now i am working full time.. +plenty of over time (pays still crap though) its time to get me some parts and this thing atleast ridable. Still not much money but better than nothing while i line up something else.

went down to bunnings.. They wanted a arm and a leg for it but it is a nice piece of equipment to have around my garage:
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And you can guess what that was for... Ole Bearings out..:
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How i removed the bearings was easy. I heated around the outer brace of the main bearing while warming up around the rest of the case a little.. i found the best way to know it is hot enough is to spit on it. You want it so it just boils on contact.. not much hotter. Take your time do not heat up a localised area or you will crack the case. Then i used a appropriate sized socket on the center of the bearing to pop it out of its brace (Love taps we dont want it crooked in there.) Some of the other bearings fell out while i was doing this.

New bearing in the freezer. (room mate looks at me funny, decides not to say anything lol.)
 

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AAnd progress is halted :D Didnt think of a good way to remove the blind bearings that is on the clutch arm side.. will need to buy a tool kit while i am at it.

New gearbox on the way, for one shaft.. The rest will probably go in the spare parts box.

Also new front axle with spacer because my spacer was missing..
 
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