Dyno performance- actual readings

[markQLD]

yes, i am a curious sort of soul.  & i 'want' to know.  & yes, i really don't 'need' to know. 
torque & rpm.  yes please !!  (thumbup)
it's been in my blood since i first cut me teeth, up in da cane fields. 

so i reckon it was time to have a dedicated dyno topic.
no, i don't want to turn this into a pissing competition, but i am interested in all dyno curves.
the good, the bad, and the ugly!

so today, i did a 2nd dyno run with Clyde, after we nicked the exhaust system off Miss J.  no, we won't go there.  :-[
but i 'wanted' to know the comparison, between the Laverda Corse 3-1 (red line), and the 'standard' factory Jota 3-1-2 system (blue line).
and this is it.  which is a little different to what i expected.  'cause i thought, maybe more up top above 7,5000 rpm?  but wasn't much.
the big variation was in the 5,500 to 6,500 rpm zone.
the only thing that was changed was the exhaust.  (and it was a different day)

note: today, the rpm sensor was picking up some interference.  the rpm dips down and the torque rockets up.
bit of a bugga. so i got Fred to add the rpm data, below the power and torque data.
no, unfortunately Clyde does not pull 194 ft-lbs.      but i'm thinking that's probably just as well ay! 

& this is my reply from a couple of weeks ago, that started a good bit of hijacking.  (hence this topic)
http://www.laverdaforum.com/forum/index.php/topic,91579.msg306919.html#msg306919

so,, be forewarned you dyno blokes.
as i've been a forum searching and will soon start to throw up a link to previous replies with actual dyno results.
  cheers,  Mark

 

[markQLD]

and here we go ........
(still a bit of interference on the rpm sensor)

today, this is Bevelman's race bike, compared with Clyde.
it only got to 113 hp for this run.  the best Paul got today was 116 hp.
but still early days.  the development has only just started.
this arvo, Paul was back talking to Redax and CES. (Custom Exhaust Specialists)

& i reckon Clyde was pulling good enough in the mid-range? 
<edit> i'm guessing that the 4C cams and the 'standard' Jota 3-1-2 are a good match ??

 

[Laverdalothar]

Hi Mark

interesting figures. For real comparison, it would be necessary to fix the lean running with the original exhaust first, which for sure would compensate some of the lower power in midrange.

also a stretch of the torque curve to make it more readable would be good.

Was this done on an acceleration type dyno or a water braked one? I assume if first one, the operator did pull the clutch lever at top RPM for getting the loss figures, right? What else have you changed on the engine besides the exhaust prior to the first testing? CCM/compression/cams/carbs?

thanks

 

[markQLD]

Was this done on an acceleration type dyno or a water braked one?

dunno Lothar,  call Fred at Procycle?  http://www.procycledyno.com.au/  it was a Dynojet thingy.

I assume if first one, the operator did pull the clutch lever at top RPM for getting the loss figures, right?

wrong.  Fred doesn't do that shit.

What else have you changed on the engine besides the exhaust prior to the first testing? CCM/compression/cams/carbs?

nothing.  absolutely farken nothing!

& your comments are always welcome.  (thumbup)

<edit>  and the first exhaust (Corse 3-1) went rich, not lean, in the mid-range.  remember, it was WOT time.

..... For real comparison, it would be necessary to fix the lean running with the original exhaust first, which for sure would compensate some of the lower power in midrange.

 

[markQLD]

ay Lothar,  here's some of your dyno results,
http://www.laverdaforum.com/forum/index.php/topic,40711.msg51999.html#msg51999
< Lothar quote>  "BTW: it is from the 180? 1200 as indicated at the top, not from the 1000SFC."
& is the rear wheel power.

<edit> conversion ?  1 kgf-m = 7.233 ft-lb

 

[Dellortoman]

G'day Mark

It would help if you identified which curve is which on your original post. All it says on the dyno chart is "exhaust change"

I assume the blue curve is the 3-1-2 and the red curve is the 3-1, or maybe the other way around?

Basically both systems are 3-1. The only difference is that one of them splits into two after the collector. It's hard to believe that what happens after the collector has much influence, so I suspect something else is going on. What other differences are there between the exhausts? Header size/length, collector diameter ...

I'm interested in this stuff.

Cam

 

[markQLD]

thanks Cam.  i reckon your another curious sort of soul ay?
but pay attention!

so today, i did a 2nd dyno run with Clyde, after we nicked the exhaust system off Miss J.  no, we won't go there.  :-[

and the dates are at the bottom.  i.e.  blue today, 'std' Jota exhaust and red (7th Nov) was Laverda Corse 3-1 exhaust.
ok,  i guess i should have explained it all a bit better and i'll try harder next time.

& on the next chart, Paul's race bike is blue and my Clyde is red.  ok?  :-*

 

[Dellortoman]

Interesting. When I had a 3-1 on my Jota, it gave better mid-range and less top end than the (Redax) 3-2-1. Opposite to your results.

Any comment o header diameters & lengths?

PS: Any lack of attention on my part could be because of the rumbo I'm sharing with my cat 

 

[markQLD]

Any comment o header diameters & lengths? 

yes.
your more than welcome to come and fuckin' measure them all up yourself !!

i am happy.  i can deal with it.  i just like to share the data.
& with enough actual data, maybe we can get to some kind of 'average' target for a given setup?  i guess not?  :-\

i.e.  i'll show ya mine,  if you show me yours.
so,,  where's yer farken torque curves Cam, old matey ??  throw 'em on the table!

 

[markQLD]

& some dyno results that Robjota shared, back in May 2009
http://www.laverdaforum.com/forum/index.php/topic,40711.msg52027.html#msg52027

and Rob, back in 2008
http://www.laverdaforum.com/forum/index.php/topic,90.msg1861.html#msg1861

 

[markQLD]

... and Reggie,  back in 2008.
http://www.laverdaforum.com/forum/index.php/topic,90.msg1807.html#msg1807

 

[markQLD]

...  and the Titanium Kid,  Dave.R's Redax special.
earlier this year.
yea,  i just luuv that torque curve! 

 

[redax5]

that is a nice clean run with Dave R's 81 Jota, was happy with that engine and the result

this chart is a bit harder to read, Dyno pull today with Bevelman's track bike
I'd call it 117hp, surely we can round it up, was damn close at 116.97hp  8)

still not happy though, we wanted 115hp but seeing as we cleared that easily now we are aiming for 120hp, we can see it is still not clean at high revs, exhaust needs more back pressure to clean the curves up but we know we are heading in the right direction
positive we can break 120hp hopefully before Paul runs out of money doing Dyno runs

 

[redax5]

Was this done on an acceleration type dyno or a water braked one? I assume if first one, the operator did pull the clutch lever at top RPM for getting the loss figures, right? thanks

Lothar,
Dynojet Dyno's are Eddy Current Load Absorption Units and the operator does not pull the clutch at high revs
not certain on why you would want to actually

and don't give us the welded clutch rod story as we have done dozens of runs now with 9 different Laverda's and not damaged a clutch rod on any of them

 

[Laverdalothar]

Mark,

92HP on an untuned engine from Laverda is only possible with a Corsa Engine, especially if it is rear wheel HP (without clutch-loss correction as you said that hadn't been done), which is typically 10% lower than Engine power (that would mean your engine puts out over 100HP). Either the engine has already high comp pistons with 4/C cams or the reading is very optimistic. Also the 1145ccm sound weird for a stock engine, as they were 1116ccm (if original 1200).

So - I think you misunderstood my question: I intended to ask what has been changed on Clyde's engine before the first run with the stock exhaust, please?

@Red: in Germany, the Dynojet units are typically acceleration type dynos (or 'inertia' dynamometer I think it's called). You need to actually pull the clutch lever to measure the loss of the drive train to get to real engine power. On a braked dyno this seems not to be necessary, that's why I asked which type of Dyno this was.

The clutch-rod welding issue only appears to happen on acceleration type dynos when you actually pull the lever at top-revs. It did not only happen to me but actually to almost everyone I know that did several tests on such dynos.

 

[KERMIT1200]

Lovely curve on Dave R's.

Red have you thought about putting a reverse tapered cone shape on the end of the muffler,similar to what is on std Monty exhaust and are you using sealed air box on the inlet side to clean up the flow of air entering?Great work.Wish I had the money to take my own engine forward.

Andy

 

[markQLD]

So - I think you misunderstood my question: I intended to ask what has been changed on Clyde's engine before the first run with the stock exhaust, please? 

ok Lothar. i did misunderstand your question.  and it is a fair question.
so, i'll make meself a coffee, gather me thoughts, and get back to you soon enough.
but the first run was not with a stock factory exhaust.  it was with the Laverda Corse 3-1 exhaust. & i had to spend as much again as the original purchase price to get the bloody pipework to fuckin' fit probably.
http://www.laverdacorse.it/shop/1000cc.html

<edit> ok Lothar.  Clyde is a '78 1200.  has 80.5 mm bore.  close enough to 1130 cc.  high compression 10.? & pumped to 205 psi.
the 1145 cc refers to Paul's race bike.  that's Redax territory.  i no nothing.  :-X
Clyde had 4C cams when i got it.  wanted to try out the F1, but i agreed to leave in the 4C for now.  early days.
has had no extensive head porting.  just a bit of a tidy up, i think?  it has the all alloy head.  i.e. no skull caps.  and has had the Redax ceramic coating treatment.  & i have not heard one 'ping' out of Clyde. has done about 8,000 miles today.
& it has Redax Mikuni flat-slides with the bent intakes.  luuverly!
also has the Redax GSXR-750 wheels.  & the Spondon alloy braced swing-arm (ex Windy Corner).
Ignitech ignition, Redax/Lex pick-up board.  & still running the factory coils.

(that would mean your engine puts out over 100HP).

thank you kind sir.

i've probably forgotten something.  but that's it in a nutshell.
to say i am happy is a gross understatement.  Clyde is an easy cycle to ride and a bit of fun! 

reckon me next dyno run will be with Miss J. my 'standard' '81 Jota.  yea, i still luuv a factory Jota.  :-*

 

[redax5]

okay Lothar, why do you want to actually measure the power loss in the first place, it has no meaning at all
we do rear wheel dyno pulls, we are not interested in working out what the possible crank horsepower may be, it is all just theoretical figures, means nothing in the real world unless you intend changing to an engine with everything fully coated with anti friction coatings, ceramic bearing races, etc
your power loss is what it is, without throwing thousands of dollars at it you cannot change it so why even stress over it

and I know what a full internal engine coating costs, my own race engine is fully coated inside with anti friction coatings, oil dispersant coatings, thermal coatings and it cost well over $3,000 to do

we do a dyno pull, see what it does
then we change something, go back and do another dyno pull, if it is better we work out what to do next
Paul is on his 33rd Dyno pull at the moment, has taken us from 103hp to 117hp rear wheel
could not give a rats arse what the crank may or may not be putting out, mainly because it has no revelance at all

is interesting what the change of exhaust did to the AFR on Mark's bike, was rich in the mid range with the Laverda Corse system, nearly went lean with the standard Slater Jota system on it today and picked up a massive 20hp in the midrange
Slaters certainly did a great job designing their pipes

as I said once before, Dyno pulls are addictive

 

[redax5]

Red have you thought about putting a reverse tapered cone shape on the end of the muffler,similar to what is on std Monty exhaust and are you using sealed air box on the inlet side to clean up the flow of air entering?Great work.Wish I had the money to take my own engine forward.

Andy

you are on the ball, change to the exhaust today was the exhaust man installed a short baffle and a small reverse tapered cone, it cleaned up the dyno run great but we still have some uneveness at high RPM so Paul went to see him after we saw him, next step is to increase the back pressure a bit more by making a longer baffle or decreasing the diameter of the pipes before the collector and to decrease the size of the reverse cone outlet

inlet side, we are just using velocity stacks at the moment but you just reminded me that I need to make custom stacks with reverse airflow technology built in to them, like the backside of an aeroplane wing, totally forgot about that, my CNC man is dropping in tomorrow to pick up another 5 sets of cranks webs that we just prepared so we can build more race cranks, he has the program already for the inlet stack shape, will order a set, believe they will be good for at least another 4hp by themselves

another 30 odd dyno pulls and we will be way above 120hp 
just love it

 

[Laverdalothar]

Hi Red,

maybe it is my misunderstanding here and sorry if that caused confusion or any other negative emotion on your side, I just want to understand things a bit better, that is why I ask questions. It is not to question the results, it is to understand how comparable they are to my figures, please. 117HP is an impressive result, even if that would be engine power.