Guys,
I know there are a few people that have some experience with glow engines on
here so here is the dilemma . I have a Saito 100 four stroke engine that is
being built into a model trike... Due to the arrangement of the power train
it has a  c/f clutch that's in line with the differential so I have no
access to the end of the engine for starting it. So I have modified a traxas
ezstart so that it fits on the nose of the engine using a sprag (one way)
bearing type HSK8 this fits on the main shaft and the final gear is glued on
to the outer shell. 

Now comes the problem...

When the engine is dry the system works fine, When it is fuelled it
backfired and blew the guts out of the bearing (the sprags reversed) its
rating is 3.2nM and an overrunning speed difference of 12000 rpm with a 8mm
core and 22mm outer diameter.

How do you 
1.	Stop a glow engine backfiring
2.	Calculate how much energy comes from a backfiring engine so I can
accurately size a starter bearing.
3.	Start the thing a different way (with an onboard starter)

There is a pic for engine control here to start it adapted from a glitch
catcher 
	Initially wait for 0 throttle then at least 75% then 0 within 1 sec
then it will provide the following
	Glow via 555 pwm for 1 sec prior to and during 
	6 sec start via power fet to xx% throttle (f629) needs about 50A of
fet the starter takes nearly 30A at locked rotor using a 7.2v nicad stick.
 
It will also double as a fail safe and glitch catcher but otherwise pulse in
goes out to the throttle servo should only need a single channel (works on
paper) not yet coded. Might be useful for car and boat starting for others I
have not seen it done before except on turbines.

Lest have some help with this one guys I am not the best mechanic 

Steve





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