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i reading a review of the gixxer750 K6.

At the crank the claimed output is a whopping 150hp at 12,000 RPM, with 55ft-lbs of torque coming on strong at 10,500RPM. Compare those figures to the Gixxer 600’s maximum 50ft-lbs of torque shoving in at 7000RPM, and peak claimed 124 crank horses at 13,500 RPM and there’s no mystery as to who has the better midrange.

what does at the crank mean?

and

what's the difference between hp and bhp?

At the crank is measured at the engine. Basically with nothing hooked up too it.

bhp is brake hp, or the amount of HP that actually gets transfered to the wheels.

Sevulturus wrote:At the crank is measured at the engine. Basically with nothing hooked up too it.

bhp is brake hp, or the amount of HP that actually gets transfered to the wheels.

ah i see... so that means the bike actually has less than 150hp right?

i heard a joke from my mechanic that a guy was asking how he can add more hp to his bike and he told the guy to remove the chain and the engine will make more hp.

VermilionX wrote:

Sevulturus wrote:At the crank is measured at the engine. Basically with nothing hooked up too it.

bhp is brake hp, or the amount of HP that actually gets transfered to the wheels.

ah i see... so that means the bike actually has less than 150hp right?

i heard a joke from my mechanic that a guy was asking how he can add more hp to his bike and he told the guy to remove the chain and the engine will make more hp.

Your engine makes 150 hp, but it looses power because things like the sprockets, chain and wheel all need to be moved as well. So some of the power is wasted in moving the bits that make you move.

So when you measure the power that is put the pavement, you have all that extra weight between the engine and the rubber. Which come to think of it is probably why there are lighter chains and lighter wheels about.

That's also a part of the reason race bikes use chains rather then shaft drives. The heavier shaft drive (plus 2 direction changes for the supplied power) reduce the power that can be put to the pavement).

Sevulturus wrote:
Your engine makes 150 hp, but it looses power because things like the sprockets, chain and wheel all need to be moved as well. So some of the power is wasted in moving the bits that make you move.

So when you measure the power that is put the pavement, you have all that extra weight between the engine and the rubber. Which come to think of it is probably why there are lighter chains and lighter wheels about.

That's also a part of the reason race bikes use chains rather then shaft drives. The heavier shaft drive (plus 2 direction changes for the supplied power) reduce the power that can be put to the pavement).

ah i see... thanks again for making that clear.

i also heard that chains are more sturdy and better for aggressive riding compared to a belt.

Yeah the chain will transfer the power more instantaneously compared to the belt because the belt will slightly deflect. That's why you'll see only chains on the race bikes.

so if the bike has 150hp... i wonder how much bhp it has.

and yeah, i know i could go to a dyno test but i'd rather not until i do some serious mods for before and after results.

bhp is the amount of hp at the crank. its called brake horsepower because the type of dyno that measures crank hp uses a brake to generate resistance against the engine to measure the hp.

whp or rwhp is wheel horsepower, this is the power measured at the drive wheel(s), this is done on the familiar chassis dyno that has the drum that is turned by the drive wheel.

shp or shaft hp is hp measured at the driveshaft, this hp measurement is used for aircraft engines but not car or motorcycle engines.

That whole article seemed like they wanted to bash the 600 more than praise the 750... Most reviews I read claim both bikes are essentially the same except for the engine output.

My buddy's got a 2000 R1 and it's 150 bhp, but rear wheel hp is more along the lines of 120 or so I believe.