04' WRF450 piston clip/splitting cases

Hey, so long story short, I made a novice mistake :/


Bought a (new to me) 2004 WRF that looked like it was in good shape. I noticed I had to fill the radiator too often as I rode it and as time went on, the exhaust and breather was smoking more and more milky white smoke, and the oil changes were getting more and more milky as well.


Tore into the motor to do my first inspection and first top end rebuild, found a hairline crack in the cylinder that cracked through and through into the water passages on the side of the cylinder.


Bought new cylinder and piston, as well as a valve shim kit. Ended up dropping the wrist pin clip into the motor :banghead:


If anyone has tips on how to get it out, I'd love to hear them. I've spent approximately 15 hours over the past few weeks trying magnets, wire, compressed air, flipping the bike, everything. I even pulled the motor and shook it until my arms hurt, then I filled it with gas and dumped it, nothing, filled it with oil a few times and dumped it, nothing.


99% of my work has been done in a small, closed off, tiled room so I don't think the clip found it's way out and is "hiding". I've cleaned that room several times praying to find a clip, but no luck so far.


I also pulled the stator cover off for more access, and still have no luck. In an act of desperation I dropped a second clip down there, and was able to get it out immediately, so the other clip has either vanished, or made it's way deep into the motor.


-Anyways, I've rebuilt the motor but that dang clip is driving me crazy. I'm tearing it back down and trying more until I am 100% certain the clip is gone, or not in the motor. I have not started the bike yet.



Can anyone tell me the minimum tools and parts I need to remove in order to split the cases? Do I Have to pull the clutch out? Do I need a flywheel puller? All I really need to do is split the cases, do a quick inspection of the internals and pull out that freakin clip! I've been pulling my hair out from this! :smashpc:  :facepalm:


I currently have the motor out, topend/piston off, and stator cover off. I probably need to pull the shift lever, anything else? please guide me!



Shift lever, kicker arm, h2o pump assembly, clutch,flywheel, kickwr gears and spring, starter,balance shafts, oil pump, shifter shaft and internal parts (this can be a little bit of a pain if you never done it before), remove all case bolts and gently pry the case apart where the "notches" are one the cases. Once you have it starting to split you can take a small soft faced hammer and lightly tap the end of the crank while holding the motor a few inches off your work space and the bottom half will separate from the top half with little effort.

The only "special" tools you will need would be a flywheel puller- can be done withouone but your taking a pretty good risk of screwing up the threads on the crank without the right tool-, a small flat piece of aluminum to lock the balancer gears while you torque them down, and obviously a torque wrench....

If the motor is out and on a bench it shouldn't take much more than a few hours with a factory service manual in front of you.

Do not seperate the two transmission shafts- leave them be if you can and installation will be a snap.

Edited by knuckleduster271

Is the stator cover off?

If so, look there, all magnetic stuff..

Could be caught up in the trans gear/forks. That's all in that same cavity.

Maybe get oil and full the case,, rotate the sprocket while shifting with shift shaft. That will get EVERYTHING moving. If the gears keep moving it's low on the bottom of case. There are oil path webs I could be trapped.... but if you had a magnetic drain plug like me, you could do the gear movement thing, and shake and tilt,, all in hopes that magnet gets that clip. The clip is too big to drain out that hole, but that's ok,, it will get it right by the hole. Drain after you pull that magnet plug,, then on last drips start looking for the clip looking upside down into that drain hole. Tilt and tip till you can see it. If you see it, needle nose twist and pull it out bend it out.

I'd do a few cycles like that before splitting case. It's there, that drain magnet will locate it for you.

The stator cover is off, i probed in there with a flexible wire with magnet for at least an hour, no luck.

I was thinking about trying the oil drain a few times before giving up. I do have a magnetic oil bolt. Maybe overfill the oil, tilt it right and smack the bars on the ground a few times, tilt it left, smack, then level the bike and tilt the front end up so the drain sits alittle lower than normal, open up the drain and immediately stick a small magnet probe in the hole as it drains and hope the flow brings it to the magnet.

Keep in mind I did try this already with engine out, but instead I shook and shook then dumped it out the piston recess, with gas then oil a few times. I was hoping to break the oil stickiness down with gas so it'd slide out. Then I used oil to try and float it out. Nada. I also did try the compressor at 150psi blowing into the stator access hole while spinning the rear tire with bike upside down. Did the same shifting through all gears and blowing through the oil drain, nada.

I want to try more but I'm alittle defeated as I have tried every trick I can think of and nothing's worked. I even rubbed 50lb magnets all over the case trying to draw it to the drain hole, and came up with nothing. It may very well have shot out via compressor but I can't find it anywhere.

I'll try running oil through it and see what that gets me :)

I have had a experience similar to yours, I used this camera, Supereyes N015 2M/6.5FT Waterproof 100X USB 7mm Endoscope Borescope Inspection Camera with LED.

From amazon, Same day delivery if your Lucky.  :thumbsup:



I used it to verify what I thought was happening inside my case before i took the big leap of splitting the case. It worked well, it plugs into the usb port on the computer, with that got on borescoping and found my mangled pieces. 

The light is dimmable and bright at its max


I got it out last week!!!! I was still waiting on parts and tools to deliver so I figured I'd keep trying. I took the motor out and the stator side cover off. Laid some towels down on the carpet and turned on the tv and fetched a fresh beer. I rocked it back and forth, flipped it around and just kept rocking/smacking the case onto the carpet to try and dislodge it. After about an hour it finally fell out, I couldn't believe it, almost surreal after spending a rediculous amount of time trying to get the damn thing out.

Now I've got a new minor issue. I was tearing it up last weekend and was attempting a rough hill climb when I got stuck in a rut and stalled. I pushed the bike down the hill and at the bottom when I tried to start it all the electronics flickered then went dead, wouldn't start. Luckily it kicked over easy though. When I got home I checked out the battery and it was really, really hot and only had 2v. It was an aftermarket lithium battery and I think some of the cells blew up or shorted or something. So I replaced the battery but since then I've had some issues with the charging system. Low charging voltage that comes and goes. Some times when I check it everything's charging great, other times it's trickling, barely charging or trickling down. I double checked all my stator/Reg wires and everything seems good, so I'll have to dig into that some more.

take a look at the stator wiring harness, and if you don't find any pinched wiring from the stator, time to get the manual and do the service checks on the stator, and complete health of your charging system and battery. also check all grounds are good.

This happened to me with one of the cam shaft retainer clips.  I spent a fair amount of time and effort trying to find it, including flywheel removal.

Turns out it did fall on the ground and escape a few feet away - my neighbor found it in about 10 minutes on the floor in a pile of tools and parts...

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