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First time....loud back fire

If this is the one & only time that this has happened, you probably will not be able to identify why/what caused it. Remember that a 2007 year bike does not have a cam sensor and relies on engine cranking at start up to phase the ignition & injectors. If by chance the ECM does lose sync during an engine running event, the ECM will force a re-phase on the fly. It's possible that this is what happened. The ECM will force a re-phase by firing the rear plug on both TDC of compression and TDC of the exhaust stroke. Should this happen, a firing on TDC of exhaust can ignite the raw fuel in the muffler.
It's very possible that this is what happen to you.

I myself wouldn't get too crazy over it unless it happens again. Now if it happens again within a few weeks, then I would dig deeper.
 
Thanks Hoople.

Yes this the only time ever it has occurred, after 6 years and 45,000 miles.

If it occurs again I'll repost and inquire about "dig'n deeper"

Thanks again.
 
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