how hard is it to change a clutch in a 300ex..??? any certain tools..?? i've never done it before..

 

Not hard. Do you have a manual? If not, you should have one to do the job. They will tell you that you need a clutch holding tool but you don't. Instead, get a 1/16 - 1/8 thick piece of aluminum and use this between the gears on the right of the clutch to hold it. Also, it is very important to use a torque wrench to get the torque correct. It is 85 ft. lbs. which is pretty darn tight so you may need a breaking bar to loosten it. Get a new right crankcase cover gasket before you start. Yamabond works great for gasket sealer. I used a Tusk clutch and heavy duty springs from Rocky Mtn ATV on mine. Loved it. Make sure you soak the clutch plates for at least a day before you install them. I think that's it. Oh, I had never done a clutch of any kind before I did mine and it took me about 2 hours. If you know how to turn a wrench, you'll not have a problem. Be careful not to lose the small tube that sits in the hole for the oil pump. After I put my case back on, I saw that thing on the floor and didn't know what it was. Took me a while going through the manual to find what it was and it is important. So, I had to take the case back off and put it in.

 

Bud gave you some good info. The big nut that holds the clutch in place is a 27mm. The nut is also staked. A staked nut has a dimple on the nut by the threads. I just unstaked the nut the best I could and backed it off with a impact gun.
Insted of putting a pice of alum. in the gears you can also put the break pedal back on and put the ex in 5th gear and step on the break pedal.
I just replaced my clutch for the first time a few weeks ago. I also used the tusk clutch kit, it works great!!
The best tool you can get for this project is a service manual. Find one online or buy the book. It takes all of the guess work out of repairs.

 

I fully agree with the above. Buy a manual, get a new side cover gasket as well as the clutch kit, and go get greasy. It isn't hard, just take your time and follow the directions. Also, many of the clutch kits will tell you to soak the fiber plates for an hour or whatever. bud is right on though, give them a 24 hour soak in whatever oil you run in the quad. The oil isn't going to hurt them as long as it is wet clutch safe.

Remember, you can do this.