compression

[dirk]

hi folks

today i have measured the cylinder compression.
the head was reworked, because the head was warped.
Squishband is reset and the sqish clearance is now 0,9mm.
both cylinder and piston are new (0km)

i have measured on both side cold at full throttle.
with open valves ~10.5bar (~152psi) and closed valves ~11bar (~159,5psi).
or was it reverse.. i dont know.. it was a long day...
the manual said that the usable range is between 7.3bar and 11.3bar.
(107-164psi)
but the last value is very high or not?

regards
dirk

[ScottaKR]

I cant see any problem with the readings youve got.
If it's within the factory tolerances, you should be fine.
Just make sure youre carb jetting is right, as the higher your compression, the more likely you are to experience detonation.
Haveing said that, if your motor is basically standard, then stock jetting should be fine till you get it on a dyno.

Don't stress too much about it. Go out and enjoy!

Cheers, Scott.

[dirk]

Hi

Just make sure youre carb jetting is right, as the higher your compression,

i have only raised the needle.
Clip is now second from the bottom.
Without many load the sparks plugs are fine (light brown)
should i change the main jet?

by the way.
is it in winter better change the main jet?


regards
dirk