wiseco piston for 03 cr250

macscr125 said:

is there any place i can get the wiseco cr250 piston for an 03 with the lubrication holes already drilled on them? or is there a place to get an OEM with the holes in it?

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I doubt it. The holes are not drilled because the exact location can be different between bikes.

Dont worry about it. You could darn near drill the holes by holding the bit in your hand. You would have a hard time messing it up.

You put the new piston on the rod. You then slide the cylinder on the bike. You reach through the exhaust port and draw a pencil line on each side of the exhaust bridge. The hole /holes then go between the lines.

It was much harder to type the description than do the job.

Don't worry about it. If you aren't comfortable doing it, don't bother. The OEM does not come with oil holes, and the Wiseco was designed without them. The piston will work fine without them, they will not hurt you if you have them but you can live without them.

Good Luck,
Joe

I would say that the recommendation is just something that has been carried over through the years. Piston technology has come a long way in the past 10 years, the holes have become less important. In the old days, some KTM pistons actually came with the drill bit in the piston box!

As for the size, as long as it is smaller than the exhaust bridge is wide, you are okay. 1/16" to 5/64" is a common range. The bigger the hole, the more accurately you have to drill it.

Good Luck!
Joe