Motorcycle Repair: Bandit 400 starting problem, suzuki gsf400 bandit, secondary windings

Question
1992 Suzuki GSF400 Bandit

Issue:  
Will not cold start.  This is a boggling issue, others have mentioned it in forums but nobody can give a solution.  The problem is 99% consistent.  

Explanation:  
The bike will not start using the electric starter, however it will push start almost 100% of the time.  Once the bike has been ridden for enough time (varies), it will then start electronically.  The cool down time until it will not start again is between 1/2 and 3 hours.
"Will not start using the electric starter"--meaning that the starter is cranking, the crankshaft is turning, but there's no firing.
--There is fuel in the carbs
--There is a spark (at least when I checked one time...should check again)
--bike runs well once it is running
--takes a solid warm up time (5+ minutes before you could shut of and start again)
--Battery is FULLY charged
--Purchased with problem 1 year ago (owner could not fix)
--planning to re-jet carbs
--I believe re-jetting has been done before
--aftermarket exhaust
--Push starts may take up to 10 tries

Recap:
--Will not electronically start cold
--Will push start most of the time
--Once running, will then electronically start

Thanks for any and all help...I have an shop manual and I am studying engineering...be as technical as you wish!

Andy Eis

Answer
Hi Andy,

Thanks for the detailed descriptions. I can appreciate the engineering studies. My son is a Industrial Engineering Senior at the University of Dayton (Ohio).

I suspect radiant heat is causing excessive resistance in the ignition coil primary & secondary windings. The best way to check is to remove the coils and test them with a coil tester after coils are up to operating temperature. The tool simulates working loads. A quality VOM may detect ohm variations, but the load test is tits. :)

A side note, try eliminating the starter button from the circuit and attempt to start the engine cold. Same for other safety switches in circuit. Jump them out as process of elimination.

Did you disassemble the starter?

Please use my email: mshively1@woh.rr.com

Respectfully,
Mark Shively