Shaft RPM vs Engine RPM on a 787 2 stroke

[patman25]

Simple question, I couldn't find it directly answered when I did some searching. Does the RPM gauge tell you the Engine RPM or the Shaft RPM? Or is it a 1-to-1 deal? I've looked at engine breakdowns and I cannot see any gearing from the drive shaft to the output shaft.

Thank you

 

[patman25]

This is on a 1996 GTX btw.

 

[hitman782]

Based on what i could find, that should be the engine RPM. Generally thats how a tach is setup. The only time i could see where it would measure the shaft RPM is if its a 1:1 ratio. I am sure Snipe can/will provide more info on this subject.

 

[Dennis]

Rpm's

It is measuring the engine speed. It is direct drive........ drive shaft is rotating at the same speed as the engine.
DAWG

 

[patman25]

Thank you.