I had a buddy with the last nMotion built 600. Not sure on hp numbers, I wanna say somewhere in the 70 range, fastest he ran was a 4.4 something on it but the guy he sold it to has got it into the 4.1's.
you can get a couple of different options on the compression ratio, on HP i know they will make some ridiculous numbers, call John at JSR and he will get ya hooked up. he doesnt get to the site often because he is extremely busy.
you were mis informed. we havnt gotten a good clean run on that bike down the track. + the nitrous switch isnt working, and the wheelie bar he had for it was a tank. we geared it down and threw some 26 tall 16 paddle haulers at it. it has been out running consistant 4.3-4.4 shee's out on the dunes just on motor with no bar. this is what it looks like through 3rd gear. it just doesnt like to keep the tires down. the current owner would also like to sell the bike. he does have another bike that weighs in at 200lbs wet ready to race that was top fuel that has went back to back 4.0's only a 575cc. it has since been switched over to nitrous but hasnt ran yet.
im not positive what kinda hp that bike is making but the tq is awesome on it for a 450 based machine. you cant go by dyno numbers. you can only go on the bikes you see out racing and performing. almost every dyno will read a different number. the head on the R is sooo restrictive that if you have the cash to spend, spend it getting a good head done with +2 valves all the way around, and get it to some one good. you could throw a 12mil and a 105.5mm cylinder on one but if you cant feed the big motor with enough air and fuel you have just wasted money.