My NC30 Dyno Results.

[CMSMJ1]

Crank power is measured off the crank and wheel is measured on a roller..

There is not a calculation to figure out gearbox losses, brake drag, chain losses and tyre slippage losses and convert a rear wheel power to crank power.

The bike Hamster had dyno'd is low on power. That is about it -the dyno might have had a correction on it that would affect it but not 10bhp worth of correction.

[viper_biker]

Hasn't this all got interesting.

PS (Pferdestärke ) is a slightly higher figure than BHP (Brake Horse Power). 1bhp = 1.014PS

Likewise, crank figure have an calculation. 1RWHP = 1.25CHP

Both of these charts are of my bike, all in different states of tune and different Dyno's.

[arsey30]

So what is an "actual hp" as shown on the chart?

Dave.

[arsey30]

Granted accurate crank hp can only be measured at the crank of course, but there is a software package covering different bikes to read out an approximation of crank hp when measured at the wheel on rollers.

My crank hp was not measured by removing covers and fitting shafts and pulleys to a dyno, but on the rollers.

Of course each bikes losses will be different, but if the original data to build the software was good, if should be close.
How can you say where the measurement was taken if it is not stated on the chart?
The wheel hp is the useful one.

Dave.

[challymo]

1. The Hamster

I'd be up for this, just let me know when it is.

[mrdidlydingo]

In gneral for run what you brung type scenarios where wheel BHP is what you count they use a conversion of around 15% losses on cars (manual transmission) 20% (automatic) I dont know what the correction for bikes is although I would presume its less (please correct me if I'm wrong) ?

The only reading from a dyno that can be taken as accurate is generally the time of day ! whoever stated that the Air fuel ratios and curves are the important information from the dyno is 100% right, as the temperature and everything else can vary the output considerably.

Hamster just because you don't have some record breaking horsepower does not mean that the bike is a shitter, what it means is you need to take a little time making sure all the obvious things are in tip top condition, after that look for signs of wear or things that need renewing there are a multitude of things which loose little bits of power but when you add them up they will easily come to 5-10BHP, even your chain tension will make a difference.

I'm not a tuner of bikes, I play with them using what little knowledge I have, I enjoy it immensly, a good result on the dyno when I have a stock reading to measure against makes me smile all day, imagine how you are going to feel when the bike runs better numbers next time.

Good luck finding the missing ponies !

With regards to the Honda BHP reference's and figures, they are fit only for the same as Kawasakis, Ducatis, Suzukis, and everyone elses, ignore them its utter crap, I wathched two factory bikes run on a dyno one after the other, each not more than ten engine numbers apart, no mods no difference in mileage (i.e. both below 40 miles) run 7 BHP difference !

[The Hamster]

Likewise, crank figure have an calculation. 1RWHP = 1.25CHP

So let me work this out from what you are saying...

On the 13th Dyno Run on the fully calibrated speedometer, my bike managed to pull peak power at roughly 48.22 RWHP. So lets convert that to CHP as you suggest, 48.22 x 1.25 = 60.025 CHP. So that would go to suggest that previously my bike had been running around 57bhp, almost exactly what it should be according to Honda in 1994, and now with a bit of fettling and fine tuning the bike has gained nearly 3bhp.

More importantly, throughout the mid-range the bike has found an extra 6bhp in general making the bike much much better throughout the rev range. It pulls harder/faster and responds quicker now and compared to what I took to the Projex it is almost a completely different machine.

[alexwitham]

hello there.
I have my stock nc30 booked in for a dyno run in just over 2 weeks.
Ill post the results when i get them. Im expecting no more than 55bhp. and certainly no less than 50!!1

[Matchlessman]

What Kevin was hoping for, is another 100% Factory Standard NC30 to go on the dyno, so that we can compare the results with what we have obtained from mine.
It is going to be hard though, even Kevin says he doesnt think he has ever seen another 100% Standard on apart from mine??

Would that be your totally standard NC30 thats got drilled slides and upped jetting??

If its a dyno shootout, would it be ok to bring along my totally standard NC23? Obviously it has a micron can and GF downpipes but apart from that and a few bits and pieces, its as the factory intended.

[Matchlessman]

Another question,

If the magic ratio is the Air/Fuel ratio of 13:1, and the only dyno run ive got of my bike shows the Af going to 12 at about 11,000 rpm does that mean that its over fuelling at the top end? You can see in the power curve that it tails off at the top as well.

The only re-jetting ive done is a GF jet kit which Graeme suggested to go with the exhaust and the can. I guess the the bike could probably do with properly setting up on a dyno but it still accelerates smoothly all the way through the rev range.