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Ok so most know by now that the one way bearings in these Fuji motors fail pretty frequently......factor in aftermarket cdi's and improper (too low) of an idle speed and we have extra stress on an already taxed part. The one-way bearing is exactly what it sounds like....it is a bearing in flywheel that only allows the starter to turn one way and disengages when the motor is turning faster than the starter can. When the bearing fails it can allow the force of the motor to spin the assembly backwards and can cause broken starter gears, reduction gears, damage to the starter itelf or in some cases damage to the cover and case halves. Another problem on some earlier Predators is that Polaris didn't torque the sprag ring bolts down and the bolts were backing out then shearing off in the starter gear. 1.) Start off with a clean quad. 2.) If I am just inspecting it I will place the two left tires in pickle buckets. It gives me a better viewing angle plus I can get away without draining the oil. IMO if you know something in the assembly has failed you would probably be safer draining the oil first and keeping the quad level.
3.) Remove the bolts holding the flywheel cover on (5/16'')
Once all the bolts are removed carefully pull the cover away from the side of the motor. Be careful when doing this for 2 reasons. One you can probably reuse the gasket so you don’t want to tear it and two there are two primary reduction gears are held in by dowels from the engine case to the side cover. It should look like this once the cover is removed
I wrapped the stator and cover and placed it in the footwell. You’ll want to be careful with this as it is a very expensive piece. I placed all the bolts in gasoline to take the oil and old Loctite off.
4.) Remove the two reduction gears and dowels out. They will slide right out. 5.) Take a 19mm socket and turn the motor over until you the key slot is at your 12 o’clock. Now take the same socket and your impact wrench and remove the flywheel nut.
6.) Take your flywheel remover and back the bolt out then screw it on to the flywheel itself.
7.) Take your impact wrench with 15/16” socket and drive the bolt in which will pull your flywheel off. The starter gear may or may not come with the flywheel but if it doesn’t just pull it off. Pay special attention to the key…..it will usually come out and stick to the flywheel magnet but it may just fall on to the ground. In my case the key sheared, the top half stuck in the flywheel and the bottom half stayed in the crank slot. If this happens to you just take a Phillips head screwdriver and a hammer and gently tap the outside edge of the key. The key is a half moon so tapping the outside of one end will rock the other end up so you can grab it. The last piece should be a needle bearing piece which you can leave in there but I remove it to inspect it. 8.) With everything removed it should look like this
And you should be left with a pile of parts like this.
At this point you’ll want to check you gears for crack, missing teeth etc. You can also check the one-way for operation by placing the one way on the starter gear and rotating counterclockwise (this will open it up) and sliding it onto the gear. DO NOT push the flywheel onto the gear without rotating it or damage to the the bearing will occur. I also check the inside case/ stator cover for rounding of the dowel holes. 9.) At this point I’m just replacing my Woodruff key so I left the one-way installed…BUT if you are replacing it you would remove the 8 bolts which will remove the sprag ring. When you install the new one there will be a flange on the bearing that will go on the flywheel side and then be sandwiched on by the sprag ring. It is next to impossible to install the bearing itself wrong but just to make sure turn the flywheel over and if the bearing falls out its in backwards. Depending who was on shift when your bike was assembled there will either be no Loctite or just was too much. If you happen to be one of the ones with Loctite soak the bolts in gas or brake cleaner to loosen it up and you may (I did) have to take a pair of pliers and squeeze the Loctite to crack it off. I’ve always done the good and tight on the sprag bolts because I don’t trust my torque wrench on lower numbers but if you have a good one the torque specs are 133-155 inch lbs (according to the shop manual) in a criss-cross pattern. 10.) Putting it all back together. Put the needle bearing basket on to the crankshaft output
Put the key into the slot. I usually give it a couple of taps with the rubber mallet to seat it in the keyway better. Next take the starter gear and flywheel and rotate the flywheel counterclockwise and it will open up and you can slide it onto the gear. Again you can[/i] just press it on to the gear but it will most likely damage it so don’t do it. Line up the flywheel slot with the key on the crank and press it towards the engine. This may take a couple of tries because the key likes to come out but just do it until you get it. Put the washer and flywheel nut (oil on threads) back onto the crank output. I then impact it on then break out the torque wrench. You will need to brace the flywheel to keep it from turning when you torque it. You can use a flat head screwdriver wedged between the pick up and the frame. I couldn’t find the right length so I used a socket and extension. I’ve used both but I like the socket better because the lip is rounded but when I’ve used the flathead I always put a piece of tubing over the sharp edge to minimize gouging.
The manual call for 111-125lbs of torque on the nut but last time I did 111 and the nut worked itself loose, so this time I just did 125 but worked my way up 111/118/125. Personal preference. Install the dowels into the case half, they will only fit in the right one. Slide the gears onto the dowels (again the will only fit onto the right one. You may have to turn them slightly so that the mesh up but when they do they will just plop into place.
At this point your quad should be in neutral and you’ll want to check the one-way again. Since it’s all back together you should be able to just turn the starter gear counterclockwise to see it spin. Keep one hand over the reduction gears (the 2 small ones) because the will spin off the dowels. Now ideally you should be able to reuse your gasket but if it’s torn it would be best to replace it. I also used brake cleaner on the lip of the stator cover and some gasket sealer to get a nice tight seal. Now just torque the cover bolts to 80-97 inch lbs. I just go 1/8 turn past snug, again personal preference, but a torque wrench would be better. All that’s left is to start it up and adjust the idle a little past where you can hear the decomp pinging. Without a tach this is just by sound but I run mine a little high because a too low will cause that key to shear and you're back to step one.
 

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Discussion Starter · #2 ·
yeah Ive got the electric dewalt too....works great. It's a heavy SOB thats for sure but it'll do the job. Hellonwheels, I should be good for awhile so you can borrow mine if you pay shipping both way but that'll be pretty close to the price of buying one. If you look in predowner's signature he found a yami puller that'll work and has the part number for it, should be easier to come across plus maybe give you another option as it should be something a yami dealer could do for you. The oneway free spinning counterclockwise is the important part, it will turn clockwise too because that will be the direction the starter would move to turn over the motor.....so as long as the oneway doesn't turn the motor over counterclockwise you should be good.. When you pull the flywheel and turn it over there is a spring that keeps all the rollers in place, anytime my oneway went the spring was visable but otherwise its in the assembly.

SPH - It would take a fair amount of carnage rolling around in there to trash the stator. IMO. Looking at how it is set up the stator should be fairly well protected from anything being on the opposite side of the oneway and surrounded by the flywheel. I'm not saying that it'n NOT possible but it would take alot. I guess a peice of metal could sneak in there and get stuck to the flywheel which (spinning around the stator like it does) would trash the stator but that kind of damage would be pretty obvious. The most damage I've personally seen was when mine chipped off a couple of teeth that sent them through the gears and and got lodged between the starter gear and the bottom of the case. The end result was new starter gear, primary reduction gear #1, gouging of the case, and a crack in the stator cover from the dowel being forced at an angle. I was able to replace the gears, file down the gouge in the case and JB weld the cover.
 

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New here and I need some help please! I’ve got a buddy who inherited a built predator 500, the thing ran great and he was told bored to the max and cammed out and I’m sure that’s the issue but there has to be a solution, He took it to a dealer and they said one way bearing so I installed one and it ran great until he shut it off and went to restart it and I diagnosed it as a failed one way, we installed another and it failed again after 2 starts this time, are there any heavy duty bullet proof one ways out there or any solutions?? Please help so he can ride again! Thank you for your time in advance!
 
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