Compression pressure in ok 907Ie engine????

[Finnpaso]

Have anybody tested, what shall be right compression pressure in normal working 907IE engine ???? One USA guy contacted to me and asked, cause he feels, that compression is not enough high. He is suffering also serious charching problems(maybe both, regulator and generator have blown).. i try help him...

[Tamburinifan]

10-11 kg/cm2 is average f a 2V 900.

[Finnpaso]

Thanks!

[jcslocum]

Even pressure is more important than high pressure.

[Finnpaso]

Btw, i check from ST2/2002 workshop manual and it says:

Standart: 9-11 bar
Min: 8 bar
max diffrerence between 2 cylinders: 2 bar

ST2 engine is same, as 907, only bigger bore.

thanks guys!

[samandkimberly]

Just measured mine - stock 907ie, 20k mi, 1k mi on fresh valve job, measured on COLD engine, with throttle open: 9.5 bar both cylinders.

I'm sure it would go up on a warm motor.

Sam

[Finnpaso]

Sam, You dont have anything to worry! ST2 workishop manual says, that pressure have to be measured after heating engine up, that fan start to work.... Your pressures seems to be ok....

[samandkimberly]

Sam, You dont have anything to worry! ST2 workishop manual says, that pressure have to be measured after heating engine up, that fan start to work.... Your pressures seems to be ok....

I'm not worried - I just thought I'd throw that in for everyone as a point of reference, in case someone else decides to check their compression with the engine cold. Right now my bike is sitting, waiting for a couple of parts, so I though I'd throw a gauge on it and see.

Sam