what is ther ecommended compression ?

[oranm23]

i have gs500 2002 67K
i dont have any problem just want to check  the engine compression

* i have another question my bike have little spot of rust  on the chassis
can i clean it with WD40 or it will cause paint problem on the chassis

thanks

[Danny500]

WD-40, Astonish, Brassol will all work fine and not hurt your finish.

What is your compression? Most 4 strokes run about 30-50 depending on the bike. As long as you're not under 30 you should be fine. I'm sure someone has the manual and will look it up for you.

Dan

[sledge]

What is your compression? Most 4 strokes run about 30-50 depending on the bike. As long as you're not under 30 you should be fine.

30-50 what?? Bar, Psi, kPa......Pink elephants???

Lets assume Psi....Suzuki quote anywhere between 142-199 Psi for a healthy engine, the service limit is 114 Psi and the (often overlooked) maximum allowed difference between cylinders is 28 Psi.

[Mdow]

HAHA i was going to say 50!! shoot im 3 and a half times that i got a like a 40-1 compression then haha i guess your not talking PSI

but ya you should be upper 100's

[ATLRIDER]

Yeah, somewhere in the mid to upper 100's-PSI.  My compression results were 150psi for the two cylinders.  Leakdown was like 2-3%, so I figure she has a few good miles left in her 

[Danny500]

Wow... i thought only 2 strokes ran that high. My ATV and old Honda 200 both run in the mid 40's PSI. The only time I've seen compression as high as 114 was in my mopeds.

Heh, goes to show I haven't checked the suzy yet. Lol

My bad! 

Dan

[Kurlon]

Wow... i thought only 2 strokes ran that high. My ATV and old Honda 200 both run in the mid 40's PSI. The only time I've seen compression as high as 114 was in my mopeds.

Heh, goes to show I haven't checked the suzy yet. Lol

My bad! 

Dan

Er, usually you can't even get a cylinder to fire much below 90psi.  If you were only getting 40psi, I'd say you were doing the compression test wrong.

Compression tester screwed in the plug boss
Throttle wide open (Or carbs removed, either works)
Turn over till it stops building compression

I've got one motor that builds over 300psi, don't know how much over 'cause I don't have a gauge that reads that high.   It's a Honda single, started life as a CRF70, it's now a bored and heavily stroked 110cc ripper.