33bhp Dyno Resutls

Originally Posted by Liam9188

Just to prove my point...
An SV 650 produces around 45ft-lbs of torque. that is then multiplied by the primary drive, whatever gear your in and final drive to give us a mechanical advantage. so that would be....

45x2.088= 93.96 for primary

Then 93.96x2.461=231.23 for first gear

and 231.23x3=693.7 for final drive, taking away say 10% for loses in transmission to make it easy is 624.33 ft-lbs of torque at the rear wheel in first.

When the same is done for top gear you end up with only 222.7ft-lbs after assumed loses.

Obviously these arn't the numbers a dyno shows us, so they must convert it somehow. Can someone fill in this gap for me? I assume it must be run in 2 gears then it can use the different figures to work out the actual amount that is on tap after all loses?

In a blind way you are looking at driving force... Very different. I cant find the damn info at the moment though. Afraid you are on the wrong tracks though...

The point is that the amount of troque that arrives at the rear wheel varies massively depending on what gear your in, as well as what revs you are at. The result you get from a dyno is more like rear wheel power ignoring gear ratios, seems wierd. Anyone can explain this in a way we all understand?

[yorkie_chris]

Push something with 1 kg of force which is moving at 1 metre per second, that is 10W (ish); or 0.01341022 bhp

Push something with the same 1kg force which is moving at 10 metres per second, and you get 100W (ish) or 0.134 bhp

F = ma
p = Fv

So with a lower gear, you are getting higher force, but at a lower speed, so the work done per time (power!) remains the same.