just received my new front sprocket in the mail...before i start this project, does anybody have any instructions before i just start unbolting?

 

you might want to use an impact (air) wrench to loosen the nut. What i did was go to the local guy and loosen it with the impact, then tighten with a ratchet, drive it home to change it out. After you get the new one on, torque it down good with the ratchet and lock the washer in place.

 

Leave the chain on and use the bike to prevent the sprocket from turning while you loosen it.

 

Yep, I had to take it to the dealer too to break the nut loose.

I could not break it loose to save my life.

 

I'm with Highbeam on this one. Be sure to FIRST bend back the tab on the locking washer, find a socket and a nice, long breaker bar and/or cheater to loosen the nut (regular threads...lefty loosey). I then find a <deep> socket of the right size to fit IN one of the holes on the rear sprocket, and turn the rear wheel forward until that socket jams against the swingarm. This locks your rear wheel in place so that you can turn the front sprocket nut as a one-man job and without rattling on your bike with an air wrench. It works like a charm.

Before I found this method in a prior post, we tried an impact wrench, standing on the brake, putting the bike in gear, etc, etc, with NO luck.

Be careful using this method on an aluminum rear sprocket as another member has suggested it could cause damage. No problems for me with the stock and aftermarket steel rear sprocket. There's an old post around here someplace where a member posted a method for using a spare section of chain to do something similar to the above, but without damage to an aluminum sprocket.

Also, I don't remove the rear wheel to get the chain off. After loosening the countershaft sprocket nut, I loosen the rear wheel, slide it forward, and slip the chain off the rear sprocket. Then replace the front sprocket and reassemble.

 

Sorry if I made it sound complicated. It really isn't, provided you have the sockets and a good, long breaker bar so you can put the torque to that tight nut! The part about jamming the rear wheel against the swing arm is simple. I use a spare socket that fits in the hole, but you could also use a screwdriver handle or something similar.

Do it!

 

I used a electric impact and it came off no problem. Then slide the rear wheel forward and chain off. Not a big deal at all. I wouldn't pay someone to do it thats for sure

 

ya its pretty simple to do. just try it first =)

 

The C/S nut is on TIGHT, like REALLY TIGHT, tighter than any other bike I have come across, but IDRIDR's method will work. I used a small piece of light rebar to lock the rear sprocket against the swing arm and a breaker bar with a 3 foot extension lever. It required some major torquing but it did come loose with little trouble.

While I am not one for babying my KLX, the shock that an impact wrench may transfer into the gearbox concerns me enough that I'd personally stay away from air tools to do this proceedure...

 

Mine was $1150.00 or so for the 351 install, can't remember what the BB carb was. Seems it was close to $500.00. Then there's the full exhaust.