"The motor isn't running at optimum r.p.m." Unless you need to run 80 mph all the time, the 6 speed is a luxury, not a necessity. and not necessarily good for the motor if you pull the rev's down...particularly on 96" stroked motors. Twin Cams love 3,000 rpm and the milage shows it. My 95" gets 45 mpg and still doesn't need oil between 5,000 mile oil changes. It just clicked over 83,000...

 

Man after my own heart! My TC only gets to run smooth and sweet from 3,000rpm. With my 21T compensator I get to enjoy that so much more!

 

That's when I use sixth, above 80 m.p.h. where it runs 3000. The motor on this bike doesn't come on hard until 3700. I don't want to cruise at that high an r.p.m. I did get 50 m.p.g. while breaking in this motor ,and never running much over 70 with the old six speed. My point was "don't expect an increase in milage by going to a six speed."

 

I have a DD6 and wish I save my money. It is OK but not worth what it cost! All so I and many others have primary noise ever since we installed them with the bigger motor sprocket, primary chain and shoe. I had to put a HB 125 in mine to get rid of 80% of the noise.

Mine runs find at 70 MPH only turning 2500 RPM and I have a bone stock motor.