Gas engine ignition timing..

[rhomodel]

I must be getting old: forgot how much mm before tdc the ignition should spark on a gas engine. The SG and BZM engines have marks on the rotor and primary coils, but I forgot at how many mm the piston should be at that point. I vaguely recall 1.5 mm, but could be 1.2 as well..

 

[Koban Rado]

The ignition coils and rotor are identical to the CMB27.
Correct, 1.2-1.5mm

 

[David Bryant]

still need to set the timing on my CMB 27.0cc

 

[rhomodel]

Mine was really off: 2.5 mm. No wonder the engine ran rough and stalled upon launch..

 

[henkie]

The one in your twin ?

 

[rhomodel]

No the Slingshot Hendrik: The twin I have not checked yet, that I suspect is an airleak...