Oh Man! I had a very similar problem with a 2007 Carpenter Racing modified bike. No dealer could figure it out. Everything like the crank angle sensor, throttle position sensor and every possible electrical connection was checked out....nothing! In two different dealers for a total of 5 months!!
Suddenly, for no apparent reason, the baby started and ran like a full bore 208 HP rocket!.
Man...we sold that baby asap!! Sell yours!
Same here with my 2007 Carpenter modified Roadster. $2300 worth of diagnostics and fiddling! Finally it ran for no apparent reason and bam! I sold it at a significant loss! No reason was ever found!!