Join Date: Jun 2011
Location: East Central Iowa
The 57h is a higher lift version(.560" vs .510") of a 37H so it should perform the same while being able to hold a bit more power on the top end.
I've used the 37 in 95" motors in both my past bikes, WideGlide and Ultra Classic, and was very happy with it. Pulls very well through the gears all the way to 6000 rpm or so. In carb'd applications it can be a bit pipe sensitive, leaving a hole in the power at 60mph cruise speeds. I'm certain this could be tuned out with EFI. Was especially bad with an early V&H Pro Pipe.
I've got an SE204 in my bike now, primarily because it's basically a 37 advanced 4* which was something I always wanted to try when I was running the 37. It works just as theory says it should, more bottom end, but is all done by 5500rpm. The 204 works well with the 6 speed gear box.
So, put the 57 in, I suspect you'll be happy with it. If you find you want more bottom end the fix is as easy as putting in a 4* advance sprocket.
2015 RGU CVO........under continuous change......