XS650 Wont stay running after battery elimination kit.

My buddy just installed a battery eliminator kit with a capacitor....The bike is a 78 xs650 He says the bike will start and runs/rides great for a while then shuts off without warning and wont restart for about an hour. I thought this sounds very odd, but didnt know if this was a common issue with these conversions. We dont live close enough for me to go and look at the bike for him so my trouble shooting has been via text message only so far. Thanks for the input!

He said it is a "Hugh's Hand built charging system capacitor. " FYI

I would hit up Hugh, he is a very knowledgeable and helpful person.

He should be able to point you in the right direction.

Check rotor resistance, they fail.
New upgrades from Mikes XS has better insulation (or join one of the 650 sites and learn to re-wind rotor )
Capacitor could also be breaking down when hot?
Is it mounted somewhere in airflow?

He's running Hugh's PMA conversion as well, I assume? Cap won't work on an EM alternator.

Definitely hit up Hugh.

Guys.....thank you for the info, I have passed this on. I will keep you posted.