Since nobody on this forum seems to have an answer to my question: 1. 6,000 rpm is way under the safe limit for this engine (for obvious reasons) which limits power output. With a 3.30" stroke, piston speed at 6,000 rpm is at 3,300 feet per minute. At 7,000 rpm, piston speed would be at 3,850 fpm. This motor could easily handle 4,000 fpm for short periods of time. It could handle 3,300 fpm all day long! 2. I'm not much interested in having someone else tell me when its time to shift!