So I recently bought a 2001 400ex and I have been doing some small tlc here and there as I ride it. Just a few hours ago my dads friend said my axel nut was loose but there is no play in my axel, although the axel nut wiggles back and forth a little bit, but is tight enough that I can't completely turn it. Also the axel nut itself is maybe 1/2" from the brake disk which also wiggles a bit. Is this bad or normal?

 

If your axle moves side to side odds are the axle bearings are on there way out. The more the axle moves the worse the bearings are.
Alright I just took the axle out of my 400ex today. Ok, so there are 2 nuts on the axle. The right is the axle nut and the left is a stop nut. Back the stop nut so the axle nut can be turned. Then turn the axle nut counter clockwise. This should tighten up the disc brake. Then tighten up the stop nut to the axle nut.
Its a good idea to check those 2 nuts every now and then. They can work loose over time.

 

Well there is no play at all in my axel. Just the axel nut is about 1/2" away from the disk brake. I'm guessing that is counter clockwise. The problem is that I can move the axel nut very slightly back and fourth,and i mean slightly(more of a wiggle, same with the disk brake). Would it be possible to take a picture of your rear end so I could see how it should look?

 

Mine is in pieces now and it wont go back together for a week or so. I need to order a new seal for it. Can you post a pic of yours?

 

Sure give me a minute.

 

Here's some pictures and a video of it. Like I said though the axel itself doesn't wiggle or anything, it feels tight like it should.

axel nut wiggle - YouTube
http://i1188.photobucket.com/albums/...e/IMG_0102.jpg
http://i1188.photobucket.com/albums/...e/IMG_0103.jpg

 

I would think it should be tight but look at the threads and see if they are messed up in any way if it was loose and rocks sand etc got in there the threads may be messed up and not allowing it to tighten all the way so back it out and inspect the threads on it

 

Thats not good. You have to back the stop nut away from the axle nut. Then tighten the axle nut. This will remove all of the wiggle. Then tighten the stop nut against the axle nut.

 

So turn the stop nut towards the brake disk then turn the axel nut in aswell? or out further? Every picture i have seen shows some or alot of thread between the axel nut and the brake disk. This is my first sport quad so its a lil confusing lol.

 

Close, the stop nut will turn towards towards the brake rotor (not tight) and the axle nut will turn towards the tire. You will feel the axle nut tighten the collar its on against the mount for the rotor. Keep turnig that axle nut until there is no movement at all.Then tightn the stop nut against the axle nut. the stop nut is there just to keep the axle nut from backing loose.