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My suspicions came true. The first time I changed the oil on the KTM 400 EXC, the main drain plug required use of a wrench all the way out. Now on the 3rd oil change, it pretty evident the threads were stripping out on the case.
As anyone with the bike can attest to.... the plug placement is not optimal. With only 3 inches spacing between the backward facing plug and the frame, I'm afraid it may require removing the engine to Helicoil the drain plug.

Checking to see if anyone else his encountered this problem. Haven't called CycleZone yet, but I'm sure it's something they have seen before.

MacWildcat wrote:My suspicions came true. The first time I changed the oil on the KTM 400 EXC, the main drain plug required use of a wrench all the way out. Now on the 3rd oil change, it pretty evident the threads were stripping out on the case.
As anyone with the bike can attest to.... the plug placement is not optimal. With only 3 inches spacing between the backward facing plug and the frame, I'm afraid it may require removing the engine to Helicoil the drain plug.

Checking to see if anyone else his encountered this problem. Haven't called CycleZone yet, but I'm sure it's something they have seen before.

Sounds like you have a problem here... Check out this thread from KTM Talk:

http://ktmtalk.com/index.php?showtopic= ... drain+plug

Let us know how it turns out.

The drain plug has a magnet. Nice to clean that off ... however ...

Most, if not all, the oil can be drained by taking out the long screen and tilting the bike to the left.

My suggestion would be: If you can get the drain plug in, put on some blue loctite and leave it alone. Drain from the long screen.

For other KTM owners: I have found that a GearWrench works wonderfully well on that drain plug.

Thanks for the tip Mike. I was wondering if I could drain the oil out the side for now. I'm considering pulling the engine anyway this winter to see how much trouble I can get into doing a top end overhaul.

From what I found out, KTM dealers have a standard kit to fix the drain plug. Pretty common issue. They use a product that is supposed to be more reliable than a helicoil.

From my reading on KTMTalk, the first thing to go are the intake valves. When you can't adjust them anymore, time for a valve job. (The valves mushroom into the valve seats. Thus you end up having to back out the adjusters. When you can't back them out anymore, time for a refresh.)

You can actually get the head, jug, and piston off of the engine while in the frame, but that doesn't help you on the oil drain problem.

Here are some pictures of my transmission swap a few years back:
http://home.everestkc.net/malsin/Motorc ... roject.htm

From my reading, when my bike gets to this point I will be sending my engine head to DJH (KTMTalk) to get after-market valves (Kibblewhite) and a multi angle valve seat grind.

safiri wrote:Here are some pictures of my transmission swap a few years back:
http://home.everestkc.net/malsin/Motorc ... roject.htm

I'm amazed every time I look at those photos. That was a much larger job than I think I could tackle unless I could sit down and focus on it 100% for a few days until completed.

The drain plug will screw up the threads if someone cross threads it or puts it back without the copper washer. Your drain plug may have had one or both of these events in the past. Otherwise people don't seem to have problems with them.

Some 450/525s have softer intake valves ('03-'07 EXCs mostly). Some (SMs) have titanium intakes that wear the valve guides and end up burning oil. But not all. If you don't wring the snot out of the motor you may not have valve problems for years, or at least that seems to be the high mileage rider's consensus. Just check your valves once in a while. I wouldn't worry about it unless you were getting ready to ride your EXC to Tierra del Fuego. (That would be an adventure!)

Stu

There is a great post on the changes (and issues) with each year of the RFS as a sticky on KTMTalk RFS:

http://ktmtalk.com/index.php?s=d75d70aa ... pic=374972

Mac:
Not sure why you think you need to tear down the top end ... For a 2002 the updates I consider warranted are:
1. Updated cam chain guide that has a screen to keep stuff out of the crank case IF a failure occurs. (I can loan you my flywheel puller.). Not sure if this is possible without breaking the cam chain, though. need to remove the stator cover, flywheel, and cam chain tensioner at a minimum. Probably need to remove the upper head (valve cover) and split the cam chain but worth an attempt to not.
2. Updated shift detent lever just below the clutch.

Perhaps warranted (I didn't do this one): Cam gear to a 2003 or newer.