[C-note]

anybody recall a ''history/habit'' of them going deeper into the ring grooves and allowing the rings to spin and eat a cylinders exhaust port??

I know i've seen topics with them dropping OUT, but do not recall them going IN,, I dunno

A friend has dropped off an ''emergency'' case to me and would like some feedback as to this issue if possible,,


Thanks,, Rusty

 

[zr sled head]

If your talking about the 500/600 then the answer is yes..................some folks report if happening multiple times with stock pistons / some claim Wiseco's stand up much better.

 

[C-note]

I know wiseco's pins don't have an issue, but I still hate the forged slugs characteristics when exposed to fluctuating temps under full throttle usage, bikes and atv's are fine, I just don't like them in sleds

but on another note, did they complain that the locator pins were falling out (what I seem to recall), or getting pushed in?

 

[94ZR580]

I have always felt that most of the disappearing locator pins are sinking in rather than coming out. I did not attempt to get the turned rings out my pistons when it happened to me to see if the pin was sunk in, or missing all together, but would you not need a big end gap for the pins to get past the rings? I did not have any other damage, beyond cylinders, to indicate a pin bouncing around in the combustion chambers.

 

[C-note]

<div class='quotetop'>QUOTE (94ZR580 @ Feb 12 2007, 12:55 PM) <{POST_SNAPBACK}></div>

but would you not need a big end gap for the pins to get past the rings?


I did not have any other damage, to indicate a pin bouncing around in the combustion chambers.[/b]

not if the pins were pounded in, this is why I was inquiring, to find out what may have happened more often


as bad as the comb chamber looked, it was impossible to tell (we have a new head)