You Are Here: Home»Featured»KTM Countershaft Seal Replacement
KTM Countershaft Seal Replacement
Quit Being a Drip, Fix That Leak
Get rid of the grunge!
If you own a KTM, particularly a four stroke, then you are probably familiar with that persistent oil leak that develops around the countershaft. After a couple of years use, nearly every bike weeps a little oil from behind the sprocket. Mine has been that way for long while now. During the last ride, my small leak developed into a very large one. Not the most enjoyable thing to happen on a long trip. So it is time to get it the seal replaced and clean everything up down there.
So here are a few tips for doing the job. It is not very difficult and with the correct tools can be accomplished in about half an hour. So why does it leak in the first place? I get asked that question relatively often. There are four main components that work to keep the oil in the motor.
The first is a small o-ring that is located on the countershaft.
Second is the sleeve that slides over the countershaft and holds the o-ring in place.
Third is the seal that fits in the engine case and around all of the above parts.
Fourth is the bolt and convex washer that keep the sprocket on the shaft. The washer applies pressure to keep all the parts pressed firmly against the o-ring.
The o-ring does the majority of the work, but if the washer looses tension it allows all the parts to move and loose their seal. For this install we are using the new hardened replacement washer from Dirt Tricks. This is significantly better material than the stock one and should not lose its tension over time.
These steps are the same for just about every contemporary full size KTM. The only difference on two stroke models is the use of a clip instead of a bolt to hold the countershaft sprocket in place.
Here are all the parts involved
In this case the convex washer has lost its tension, it will spin freely with my finger
My prefered method for removing the countershaft bolt is to use my foot on the rear brake pedal while loosening the bolt with a large breaker bar
Here you can see the spacer as it fits over the countershaft and into the seal
On the left is the very worn spacer, replacement spacer on right
If you do not have a seal puller: To remove seal, drill small hole and carefully insert a drywall screw just a few threads until it grabs