View Single Post
Old 03-02-2013, 05:52 AM   #451
Gnarly Adventurer
Joined: Jan 2011
Oddometer: 132
Originally Posted by Cortez View Post
First bold re: revs - That's amazing. 6th gear is probably an overdrive or close,
just like on the NC700. That's the same revs I had on my 650R (which has
50% more power).

Second bold re: vibrations - That's EXACTLY what I said would happen in
this and other threads when people asked me why I consider the NC700
to be a better choice.

It vibrates because of the 180 deg. crank, and that drove me crazy on
my 650R. Can't be as bad on a smaller engine, but still, all things equal,
I'd get the 700 just because of the 270 crank. Screw the weight difference,
the bike feels 100lbs lighter then it is.
My marks on harmonic vibrations wern't that high, though I can't see how a 180 crank should have different harmonic distortins compared to a 270 crank. They should have equal free forces and free moments (figured they have the same amount of countershafts and they are placed according to their crankshafts).

The parallel twin of the NC 700 is just really cultivated. I think if it had a 180 crank it would vibrate as much as it does now.
Reason a V-motor compared to a parralel twin (which has a 270 crank) has less vibrations is (I think) because the pistons are actually removing free forces from eachother. A V-motor is naturally better balanced.

I could be wrong on some points.

I'll try look that up this week if I find a few hours, should be interesting.

I'd go with the 700 as well. Only thing I really don't like is the filler placement but many people already said that with the right strap on thingies it's a non issue. The 700 should be a 300K motor.
Bugz is offline   Reply With Quote