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JimmyHoffa · 11-16-2007, 11:01 AM

...assuming a normal gear system efficiency of 75%, this makes perfect sense...

40hp at the crank * .75 = 30 rwhp

I realize there area a few other variables, but this gets my point across. There's also a chain drive involved, which is no good (as compared to gears) so it's possible that the engine has a little more than 40hp at the crank (insignificant) to translate to the ~30 at the tire. (...that actually matters.)

30 is the number that actually carries value. If your engine is screaming out 60-horses, but you have a 50% efficient drive train, you're still staring 30 usable horsepower in the face.

11-16-2007, 11:01 AM	#24 (permalink)
JimmyHoffa C Rider Join Date: Jan 2007 Location: east central MO Posts: 27	...assuming a normal gear system efficiency of 75%, this makes perfect sense... 40hp at the crank * .75 = 30 rwhp I realize there area a few other variables, but this gets my point across. There's also a chain drive involved, which is no good (as compared to gears) so it's possible that the engine has a little more than 40hp at the crank (insignificant) to translate to the ~30 at the tire. (...that actually matters.) 30 is the number that actually carries value. If your engine is screaming out 60-horses, but you have a 50% efficient drive train, you're still staring 30 usable horsepower in the face. __________________ 2003 400ex. Complete overhaul. Pro Armor nerfs and bumper. PC black frame. Razr rears, w/fronts to come. FMF Hi-flo header coupled to a Titanium 4 can. Front shocks, bars, swinger skid and filter pending. Ask me anything. I've touched all the bolts.