Piston oversize and compression

[sdkx500]

I have a couple of questions.

1.  When taking top end compression do u take it with the bike warm or cold

2.  Has anybody used the prox kits.  At what point do u go to the +.01mm oversize?

Thanks for the info.

T

[sdkx500]

Dumb question?  

[kawdude]

I believe compression is done cold.  Why do you want to go to the oversize?  I went 2mm over for the bigbore.

[gowen]

Nope! Sorry, I believe you can take a compression test while the bike is cold, I've always done that, maybe I was wrong.

Also, proX I hear are like stock, cast and about the same, nothing special. I would keep to the standard size until you get piston slap. Maybe that is bad advice, but I would not move to any oversized pistons unless you get it bored for correct specifications.

[gowen]

ahh, beat me to it Kawdude..

[mikesmith]

You can always contact Pro-X and get it from the horses mouth!There are no dumb questions,only the ones you dont ask!I wonder on a compression test cold because every thing expands to size as it warms up,but then you need compression to get the bike to start.So Id say cold to,but thats someting to think about.

[sdkx500]

Cool thanks for the input .  I will run one cold and see if im within limits.  No slap I was just reading and found the barely oversize piston which said it was for mildly worn plated cylinders.

Thanks again

[kawdude]

Yeah pro-x has numerous "halfsizes" for worn plating.  Contact Forward Motion and see what they can do for replating and piston...excluding the porting.

[teamgreen500]

Get your motor torn down and take the measurements as indicated in the manual. The gap or 'Difference' between your cylinder and piston determines what "size" piston you need.

Get this! Johnny, at Kawasaki/Team Green says run a piston as long as it mic's out well. They become "seasoned" and can last virtually FOREVER; However, "Wear" is key! If you're really concerned about this, you can have a good "tuner" or "Engine Builder" measure this for you and advise you as to which piston is right for you.

Good luck and Speed Safely!

Manny

[sdkx500]

Manny Do you just keep slapping new rings in periodically?  I just get worried cuz my 250's always went through pistons and the big green seems to last forever

[teamgreen500]

I'm on my second or third set of rings on this piston (2nd piston). I'm lucky enough to have REALLY good assistance in these matters. In other-words: I let a real engine builder tell me whatr I need and when.

Manny

[sdkx500]

So I pulled out my old inherited compression tester.....busted!  Went out and got another.
I read the directions on the package and it says to take compression on a warm motor.  The clymer manual also says to take compression on the warm motor with the throttle held wide open.  I took a cold compression test of 92lb.  I will take a hot one and post the difference in case anybody is interested.

[Paul]

So I pulled out my old inherited compression tester.....busted!  Went out and got another.
I read the directions on the package and it says to take compression on a warm motor.  The clymer manual also says to take compression on the warm motor with the throttle held wide open.  I took a cold compression test of 92lb.  I will take a hot one and post the difference in case anybody is interested.

Low service limit is 110. You need a topend

[sdkx500]

Paul is that a cold or warm compression reading?

[Paul]

Paul is that a cold or warm compression reading?

Warm, always @ normal operating temperature.