I see that higher displacement increases the HP but does this also increase top speed? Everything I have read talks about HP which to me is torque and how quick a bike can get from 0-60 etc. Thank you ahead of time.

 

Large torque and hp increase, across the entire rpm range.
Scott

 

My 1250 with extra trimmings ran a 121.44 mph in 4th gear at 7600 rpm with stock gearing. Depends how much POWA you add. And of course, gearing, Redline ect

 

 

A good 1200 can generate about 85 ft/lbs or so, and cam/head/compression/intake and exhaust will dictate hp.
Scott

 

Yes. If you do a 1250/1275 mod, for example as per Hammer, your engine will rev much higher than stock, which along with the extra HP will enable you to ride a darned sight faster. Torque is what accelerates you, HP give you high speeds.

 

Read this, FYI: this was not written by Dan Dunn, the current and sole owner at NRHS.

http://www.nrhsperformance.com/tech_power.shtml

 

"torque is what accelerates the bike, horsepower is what maintains the speed"

 

Primary , transmission and final drive gearing it what is going to manipulate your top speed capability. The thing that goes along with that is that your are going to have to have enough engine power, both torque and hp in order to have enough power for it all to work. Do you have a desired top speed in mind?
M