???? for KTM 300 owners

[evenslower]

First, I'm not looking to start a debate on the merits of Wiseco vs. OEM pistons but I do have a question. I'm curious to know what others have done when time for a new top end. I've used Wiseco in every top end I've done but this is the first KTM I have tackled. I have heard that the 300's may have issues with Wiseco pistons. I know that even the 250, 300, and 380 are bascially the same engine with different bores but only the 300 comes stock with a forged piston. The 250 and 300 both come with cast. Why the difference?

Also I have read about two different cylinder numbers or letters and relation to the size of piston you will need but Wiseco only makes one size unless you are talking overbore. Is this correct?

I'm sure there are folks out there who have used Wiseco which is what I'm leaning toward but can I expect to encounter any issues or anything in particular I need to be aware of to order the right thing first time out?

 

[fatherandson]

I use Wiseco in my '99 300.  No problems.

 

[VOR 492]

I have a Wiseco in my 2000 300 EXC, No problems either

 

[pedesktm]

I've been running Wiseco as well. Many a miles, never a problem.

 

[MikeS]

Eric sent me a Wiseco with the replate job he did and it works very well.

 

[bikeguy]

You won't have a problem using a weisco. The thing is, the KTM's OEM piston rarely wears out. I mic'd the piston in my 96 this fall and it was well within spec. I replace the rings every year and it just continues to go. The weisco's don't last as long, but are cheaper.

So, you decide, either is a good choice.

 

[trailblazer]

Evenslower:

I have used both oem and wiseco. The first oem lasted about 2300 miles. Still within tolerance(piston/cylinder clearance), however, it had the start of a hairline crack across the intake skirt. Caught it just in time.
Used a wiseco for 1500 miles. Piston worn enough to be out of tolerance for piston/cylinder clearance;and, the ring end gap was worn beyond tolerance too.
Installed a new oem piston after the wiseco. will chanage rings at 1800 miles this time. perhaps piston won't start a crack in the skirt?

Either set up will work. Put in a new wiseco every 1500 miles and you should be fine. The oem will last much longer if you change rings when required-but, costs almost twice what the wiseco does.

Trailblazer
'99 300exc (5600 miles)

 

[evenslower]

Thanks for the replies. As soon as my engine manual gets here I'll pop it open. Its got the original piston and rings in it and its seen its fair share of use. I'm interested to see how the piston "measures up" once its out.

Thanks for the replies.