CRAZY SERVICE INTERVALS: MR. KNOW-IT-ALL

Mr.Know-it-all,

I have a new KTM 300XC-W TPI. At least, in my opinion it’s new. I have only ridden it twice, but both were fairly decent rides, lasting pretty much all day. I would guess that the bike has over 10 hours. Looking at my owner’s manual, it appears that KTM thinks I have already worn out a top end. Can that be right? Only 10 hours before it needs a new piston and rings? My 1997 CR125 went over a year between top ends. Have two-strokes actually become less durable?
Bob Anderson
via [email protected]

Bob,
Short service intervals are nothing new. For years, Suzuki has said you should replace the piston and rings in the RM-Z450 every 12 hours. This is simply a worst-case scenario. I’ve looked through the manual on your KTM and found a number of oddly short service intervals. Here are a few:

1. Change the oil pump at 80 hours. Only clean oil goes through the pump, so it should easily last 200 hours.

2. Change the piston and rings at 10 hours. Unless
your name is factory KTM rider Taylor Roberts, this is laughable.

3. Change the piston and rings at 40 hours. For normal riding, 100–125 hours makes more sense.

4. Change connecting rod and all engine bearings at 40 hours. Actually, 350–400 hours is usually when this is required.

5. Change in-tank fuel filter at 40 hours. It’s a big filter and should easily go 80+ hours—unless you get a bad tank of fuel with water.