Well, the survey has gone sideways in this forum, which is not unexpected.
The clonk happens when the engine is lugged at a too low rpm. The compensator, if it had a mind, would be losing it. It can't deal with that kind of torque without doing something to relieve the stresses. S&S, as well as Morgan, has always stressed staying above 2700 rpm for a good reason. This does not a happy engine make! The only time I hit these low rpm's is when I am under no load and coasting to a stop.
Your range is from 3,000rpm to just under 5,000rpm. It gets ragged at the top end. This engine will cruise all day at 3,600 rpm without complaint. This engine is like a diesel engine in that it is all about torque. There is a very narrow range of useful power. Within that range you've got gobs of it!
