thankful for a wiseco.

[b4himdude]

. the other day i had a good ride going on the k'5 that i just had sleeved and a brand new wiseco in it. but all of a sudden the bike dies. i can start it but i cant throttle it or it dies. the s**t thing 9well the first s**t thing) is the fricken hill i get to push the bike up. god im out of shape. but anyway got her home and pulled the plug . the gapper prong was bent over into the electrode. i decided to remove the cylinder to find that the needle bearing around the wrist pin had disintegrated and pieces were being pulverized until the right amount of them hit the plug and killed the bike. i really dont think a pro x would have taken the abuse that wiseco did. the crown was pitted the head was pitted. the cylinder faired well . but i dont think a nicasil would have. but nothing was broken or cracked other than that bearing. anyone have any ideas why the needle bearing crapped. i have two questions . on the wiseco it calls for two small holes drilled in the piston's skirt of the exhaust bridge side. i dont know if the k5's is a bridge buti never drilled those holes. plus why doesnt wiseco send a needle bearing in their piston kits? any thoughts?
s

[umberto]

I had used Wiseco forged pistons for my previous projects, but everyone was so passionate about Wossner I figured I would give it a try.  I have to say I was very impressed with the Wossner I got for Goliath, and the price was comparable to the other brands.  It also reassured me knowing that guys like Motorrad and Sandblaster put a lot more stress on their Wossner pistons than I do and are still impressed with them.

[sandblaster]

Wossner, Wiseco, and many others do not give you a wrist pin bearing.
Why?
Probably cost.
Wossner gives you a wrist pin bearing when you buy a rod kit from them.
Look at where the exhaust flows out of your cylinder.
You see a big hole with no bridge running vertically down the center of it.
So drilling a hole in the piston there will not help you.
However... There are some other spots where you could drill some holes that would help with lubrication on some troubled area's.

http://www.oem-cycle.com/forum/viewtopic.php?f=5&t=602

Oh, and Motorrad does a awesome head cut.....

[Foxx4Beaver]

the last wiseco I got 4 years ago, the ring lands were wavy.
never bought another since.

[USMC 500]

I had a Wiseco in my KX500 once...............ONCE!!

[mikectanker]

I'll never buy another wiseco. Never had a prob with cast pistons, but I don't re-ring. I always replaced the whole top end

[b4himdude]

I've also had wiseco pistons with the wrist pin circlip grooves machined wrong....  and the ring lands machined wrong....   very bad percentages

Yep the mains were brand spanking new. Which doesn't make a difference. You're absolutely correct they should be replaced. But so far so good. I just washed the bottom end out with two stroke oil and air. Then ran a clean rag around with the crank. Like I said I agree but so far so good