ABF power

Isn't there? I know you said there isn't on your dynos - but aren't other dyno people somewhat notorious for being a bit generous in their conversion from wheel to engine power?

cheers, clive

It wasnt a troll you just opened your mouth and crap came out that you realised later you couldnt support.

First couple of posts, maybe, but I appeared to have grabbed an accidental catch, so it would have been rude not to have carried on.

Its simply not possible to give a flywheel power figure on a chassis dyno no matter what the manufacturer claims. The only valid data on any chassis dyno is rear wheel hp. All they give you is a measured bhp loss or a negative run down figure of the transmission while not under load.over the same speed range. It can be added to the power graph and give a good aproximation of flywheel power though but thats all. Its a valid measurement in its own right but it cant measure the increased losses that loading the helical gears and thrust bearing loads and subsequent oil heating that occurs..It may only be a small percentage of the total transmission loss but it cannot just be ignored. If any of them actually claim otherwise then they are breaking the law with false advertising claims. My own software is capable of doing it. But its locked out in the retail version. It was for our use only to measure the drums windage and bearing losses from 250mph down to

12mph while free running without a vehicle so that this could be removed from all subsequent runs and the dyno reads 0bhp while the drum naturally slows by itself.

Added

After re reading your post I have to add that the extra losses caused by the way chassis dynos measure run down losses are actually too low rather than too high because they actually dont measure the extra losses caused by the torque or load in the gearbox and therefore ignore this component of the total loss. So the negative transmission power curve they reverse and add to the rear wheel power curve is actually a little too small. In other words it is going to show a lower "flywheel" figure than the correct one.

What about front wheel hp? Or is that not valid? ;P

Negligible on a motorbike anyway.

(c:

Well I sold 5 bike dynos to every car one. And I was mainly interested in bikes so my mobile unit was a bike dyno. And you dont get many front drive bikes! And I dismiss front drive as utilitarian shopping trollies! As long as they go at all who cares!

Oh, I'm sure there's a correction factor you can apply.

Some car and bike dynos that were converted olde worlde water brake ones actually used a load cell on the front wheel mounting to measure the push or torque. Crap idea crap dynos but does that count? You calculate power from the push (same as rear wheel torque) and rear wheel speed and engine rpm... It works but its shit!

Negligible on any real vehicle (Mk2 Golf GTi's excluded, natch)

No dude you're just making yourself look a c*ck heh.

Making?

I'd have said..

"Look?"