Dyno Talk - demystifying the Wheel of Disappointment.

[Sideshow Pob]

Here's the thread I've been promising to start for a long time.

So, to lay out the land, I own a Dynapro S125LC dyno - https://dynapro.co.uk/ - which some people regard as the 'tuners dyno'.  It's probably the second most popular dyno in operation (in the UK) behind the Dynojet.  Although I do have some experience with the Dynojet machines, I am much more familiar with my own Dynapro, obviously and actually I haven't been near a Dynojet for a good few years now.

Here are some subjects which we can discuss until you are totally bored with the whole thing.

1. Correction factors

2. DJHP - Crank vs Rear Wheel

3. Air Fuel Ratio (AFR) measurement

4. Calibration.

5. Load Control

6. Cowboys of the dyno world!

7. Tips and tricks to get better results

8. How to dyno an electric bike and why its difficult.

Plus anything else you fancy chatting about...

 

 

[David W]

Here’s one to get us started.

Same bike, same CF, same model of dyno, different number!

 

[Gobert]

No.6.............."sir, sir, sir...I know!" 😉

[peter30]

Actual nuts and bolts of fuelling/ignition tables when flashing ecu. I take it that things like Woolwich do the whole rainman thing and simplify how you trim them, as opposed to chris at CJS telling me that 12d in that table is the one for changing the dash message!

 

[peter30]

And faraday cage for the dyno cell, obvs!

[Sideshow Pob]

I'm going to put here now 7 images from the screen of my dyno.  They are all the same run of a 2023 ZX10R and they each have a different Correction Factor applied to them.

The Correction Factor is a method to allow the dyno results to be compared even when the climatic conditions vary.  Therefore the 'None' setting is fairly useless (but has a reason for being) and then you'll be able to see the differences between SAE, DIN, ISO, ISA and EEC.

Here we go...

Here is NONE with a figure of 209.18bhp

[Sideshow Pob]

Next we have SAE with 200.61 bhp

[Sideshow Pob]

DIN comes in at 206.05 bhp

[Sideshow Pob]

Followed by EEC with 201.86 bhp

[Sideshow Pob]

ISA has 207.93 bhp

[Sideshow Pob]

And finally for the correction factors is ISO with 207.93 bhp

[Sideshow Pob]

And finally, taking us into the world of DJHP and what happens when you click that box, here is the same run with the DIN correction but what Dynapro say is true Rear Wheel bhp (without DJHP correction)

Thats 169.73 bhp

 

[Gobert]

2 minutes ago, Sideshow Pob said:

And finally, taking us into the world of DJHP and what happens when you click that box, here is the same run with the DIN correction but what Dynapro say is true Rear Wheel bhp (without DJHP correction)

Thats 169.73 bhp

 

WOW!

[Sideshow Pob]

So that's the same run with 7 (well 6 because ISO and ISA appear identical) results.  Which one do you want printing off to show your mates down the pub 🤣

[Sideshow Pob]

1 minute ago, Gobert said:

WOW!

36.32 bhp disappeared, just like that!

[Sideshow Pob]

Thats around 17.6% 

[Gobert]

1 minute ago, Sideshow Pob said:

So that's the same run with 7 (well 6 because ISO and ISA appear identical) results.  Which one do you want printing off to show your mates down the pub 🤣

There's an awful lot of people riding around think they are dealing with 200hp at the wheel..........🤣

[Sideshow Pob]

26 minutes ago, David W said:

Here’s one to get us started.

Same bike, same CF, same model of dyno, different number!

 

I cant quite see the numbers with the Dave Cooper Racing print off.

[David W]

2 minutes ago, Sideshow Pob said:

I cant quite see the numbers with the Dave Cooper Racing print off.

It’s was 149HP at DC and 146HP at BSD few weeks later. 2003 Fireblade with Arata system and Power Commander. It was a long time ago and I had the printouts on Flickr!

[Gobert]

Just from that info, it's pretty obvious that all the "near 200hp with a system and a flash but other wise standard motor" are at the crank..............every day's a school day.

[Gobert]

@Sideshow Pob is this going to be like wiki leaks and you'll end up in hiding............?

😁

[David W]

Makes you wonder if any manufacturers have a ‘no dyno testing’ rule on their press bikes these days?

I’m still unimpressed that there has been unchallenged acceptance of manufacturer claimed figures in recent years when everyone used to roll their eyes and wait for a dyno test of a new bike…

[David W]

31 minutes ago, Sideshow Pob said:

And finally, taking us into the world of DJHP and what happens when you click that box, here is the same run with the DIN correction but what Dynapro say is true Rear Wheel bhp (without DJHP correction)

Thats 169.73 bhp

 

My Fireblade printout above is a proper rear wheel HP for a 2003 bike with a full system and Power Commander.

If the latest 1000cc bikes are only 25HP better I’m suddenly a bit unimpressed.

[Jenny Pryde]

27 minutes ago, David W said:

My Fireblade printout above is a proper rear wheel HP for a 2003 bike with a full system and Power Commander.

If the latest 1000cc bikes are only 25HP better I’m suddenly a bit unimpressed.

Especially when you factor in the lighter weight of a litre bike from 2003...

[David W]

Found the printout when the Fireblade just had an Arrow can and PC on it too (ignore where it say full system. It wasn’t).

 

[Sideshow Pob]

It annoys me that I cannot find how the Dynojet WinPep software can be made to select and deselect DJHP.  If anyone knows how this is done and how it can be seen on a printout from a Dynojet dyno I would love to find out.

[David W]

1 minute ago, Sideshow Pob said:

It annoys me that I cannot find how the Dynojet WinPep software can be made to select and deselect DJHP.  If anyone knows how this is done and how it can be seen on a printout from a Dynojet dyno I would love to find out.

I’m assuming it’s something that’s been developed way after my dyno printouts that are 15+ years old!

[Sideshow Pob]

14 minutes ago, David W said:

I’m assuming it’s something that’s been developed way after my dyno printouts that are 15+ years old!

From what I've seen, DJHP has been a 'thing' since 1985.  My gut feeling is that it was built into Dynojet software and not something that could be selected or deselected but I would love to be shown otherwise.

[2moto]

@Sideshow PobHow are you with dyno'ing 2-strokes?

[Superdunc]

3 hours ago, Sideshow Pob said:

From what I've seen, DJHP has been a 'thing' since 1985.  My gut feeling is that it was built into Dynojet software and not something that could be selected or deselected but I would love to be shown otherwise.

That's my understanding. Dynojet horsepower are smaller than everyone else's, so you can fit more in.