Does anyone know what the relationship between the 2 is. A motor that makes 150 psi cold .... what would it be when hot...yea I know hot is all that counts...manual says so... Has anyone measured cold compression and hot compression for the same motor and what the correlation was.
Funny...they talk of cold leakdown but hot compression.
Cool.
Srinath.

 :mrgreen: I FINALLY GET TO REPLY TO THE GREAT GURU!, seriously, shouldnt be that drastic of a difference. at mmi we had a lot of times checked them cold, a lot of the bikes wouldnt run. (were rigged that way). tried  both on an import sportie (canadian)cant remember the exact amount of difference though. just remember this wise saying. "all 4 stroke engines run on the whore-house principle.                                    suck squeeze bang blow.
this came from one of the most knowledgeable people in the industry charlie cavallo at mmi. seriously, there may be people out there that can tell you more. but try it yourself on your gs cold/hot, see what you get :mrgreen:     sorry i couldnt help more, my numbers are hidden amongst eleven binders of class notes.

NO NO no!! youve got it all wrong...

If the Knifner pin is aligned with the left handed floggle gear, while cold, the motor will have a higher compression (especialy with flux capacitor mod).

Now, taking into accound the varying blinker fluid levels, and its affect on the graduated oil's octane level during high- friction-less periods... During a warm run, the motor's compression will vary. Unless you measure it with a Tape measure, and bubble gum used as a plasti-gauge. HAS to be CHERRY bubble gum!!

Also, take into account the rolling friction of the piston return springs, and their measured slack. NOW, all things being equal, and with the motor in a vaccuum, one could successfully measure an inaudible difference in sound levels, associated with high vs. low temp. compression. OF COURSE, if the air compressor is bad, or leaking, all that is just garbage.

Not only is Rashad a man whore, he's also a wise ass

Quote from: johnNot only is Rashad a man whore, he's also a wise ass

I think you mean ass wise?

I think it is a MECHANIC PROBLEM
have you considered taking your POS to a shop? :nana:

What? I was being serious!

Shut up all you dolts...Well except Yamahon...whatever
I measured it...
140+ left and 145- right. Same motor made 155 left and 160 right. So the diff is about 10%.
Ooo Rashad you have way too much time on your hands.
Cool.
Srinath.

well i guess there is a correlation between the cold comp and hot comp.... and it's about 10%......

now grasshopper,
what does this tell you......

absolutely SQUAT!!!!!!!!!!
because nobody cares about the compression when the engine is cold and parked in your garage.

the compression when the bike is running/hot.....that actually might be of concern.....to a mechanic


just  a little $0.02 from a DOLT :nana:

have you CLEANED!!!!!!!!!! your carbs
or looked for that oil leak??...the suzuki valdes :mrgreen:
or lubed your chain???

Ok well most of my problems are when the bike is cold. Startup and power issues. When warm the only thing it does is act like the revs want to hang like its lean and then drop very very low like its rich and then back to the ~1100 I have it set to.
OK now with the problems as they here is some info I haven't told you. At 8K miles the bike had a barnett clutch in it, had allen case bolts that were drilled for safety wire on the right side and the on left side was a case that looked different from the rest. So My bike could have been a race bike. I suspect the thing has had wiseco pistons in it. The bike is smoother than any GS I have ever ridden and it is the only bike that will shake its tail at idle when on the stand but once the bike is rolling its better than anything else I have ever ridden. OK I therefore believe it was taken parts fitted with wisecos, balanced and set to where it is right now. Now forged pistons expand more when they get hot and so if the bike made low compression when hot and good compression when cold I know that it has appropriate behavior for what it has been fitted with.
I haven't ridden the bike after that. Its awaiting leak fixing and carb work.
Cool.
Srinath.