09 yz450f front sproket leak

[charles_guy91]

I just put my bike back together after a winter tune up, never touched the front sproket. Never leaked before but as soon as i started her up a low leak started dripping from my front sproket. I did put her on her side so i could open up the clutch. Would that have caused this? Anyone with advice would be awesome. Thanks!!

[yz450fcranker]

maybe its time for a new sprocket

[dirtcrow]

Your counter shaft oil seal might be worn and needs replacement.

[jratcliffe3]

New seal needed

[dgcars]

Remove the sprocket, pop out the old seal and press in a new one. Give everything a thorough clean first. ?

[RiderX]

If you have any problems getting it out one trick is to run a small wood screw into the metal part of the seal a little bit so you have something to grab a hold of to pull it out.

Oh, and don't forget to lube the lip of the seal up with some motor oil before you install it.

[charles_guy91]

So got my new seal, tried a few times to get the old seal out with no luck, tried the wood screw idea but couldn't get it to hold, maybe it was to big of a screw, gonna try again tommorrow. Any more tips would be greatful. thanks again guys

[grayracer513]

Two approaches to take:

First:

1. Using a punch or screwdriver blade, tap around the edges of the seal, driving it IN a small amount. This will break the bond between the case and seal.
   
2. Using a wire hook, machinist's pick, etc., pull the seal out.
   

Or:

1. Remove the steel collar from the output shaft
   
2. Insert a tool under the seal and pry it out
   

You can often just catch the outer edge with a small screwdriver or knife blade and pluck them out that way.

If the collar doesn't want to slide off:

1. Tap the output shaft straight in toward the opposite side of the case. This will break the bond between the O-ring on the output shaft and the collar.
   
2. With the trans in gear, grab the collar with a pair of pliers and turn it on the shaft as you pull.
   

• There is an O-ring on the shaft under the collar. Replace it.
  
• The collar may have a groove worn in it by the seal. If so, replace it.
  
• Don't install the seal too deeply. Insert it no farther than flush with the case.
  
• The undercut side of the sprocket (if it has one) goes IN.
  

[charles_guy91]

Using your advice got it off and new one on! Works great, get some good riding in this weekend finaly thanks!