450 YZ COUNTERSHAFT SPROCKET

[ktmmax]

My best friend has a 450 YZ (2003). It appears there is an oil leak at the countershaft seal. It looks like a double nut setup on the sprocket and I tried to take the sprocket off but the nut won't budge. Any tricks to this? I don't have a manual on this bike so I am looking for help.

Thanks ?

[GreggT]

There is only one nut. I'm sure you did but did you bend the lock washer away from the nut. I use an air impact to take mine off but don't remember if it is a backward thread or not.

[felony]

it'll be easier if you leave the chain on and have somebody hold the rear brake while you hit it with an impact wrench,it should be standard threads,"righty tighty,lefty loosey" ?

[noslo98]

When I change mine i usaly sit on the bike and hold the back brake whie using a breaker bar to bust loose all though air ia a lot nicer when your gearing at the track somtimes you dont have acess to a compressor.

[Scooter426]

yep rear brake dude.

impact wrench/air assist helps.

[grayracer513]

When using impact wrenches, air or electric, DO NOT "hold" the sprocket by placing the transmission in gear. The battering the gearbox will take will not be beneficial.

I can usually just grab it with a rag in hand and run the nut off or on that way, but a rag and a big pair of pliers, or the chain and brake method are OK too.