Laverda Engines - Fully Tuned Ex-Factory

Paul Marx said:
But then, they never got much further than the factory gate.

Paul
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:D :D (bigthumb)

I agree with Tippie, production bikes rarely attained the factory performance claims, especially the early triples and the air-cooled 750 twins.  This was proved over and over again by contempory magazine road tests, dyno results often lacking as much as 10-12hp to the factory claims.  Those claims were usually based on a properly set up and tuned, possibly blue-printed example, run on the dyno on a very good day, sun shining and all planets in line... rarely able to be replicated with a bone stock engine.  In the case of Laverda, this changed with the introduction of the 120? engines.  These consistantly lived up to the factory specs on the Moto Witt dyno back in the 90's.

Yes, the motorcycle engines of the day were in a pretty high state of tune, but running them at their max was usually venturing on very thin ice.  Thousands of blown engines of all sorts back in the day are testimony enough.  A comparably rare thing these days.

I see loads of potential in almost every old Laverda engine I rebuild and go to lengths getting valve seats right, inlet stubs lined up and carb/ignition settings spot on.  Don't normally run these engines on a dyno, but the result is usually quite surprising for most owners.

piet
 
"Thousands of blown engines of all sorts back in the day are testimony enough.  A comparably rare thing these days." Happens reasonably often with modern bikes at races around here. There were eight (!!!!) Panigales that blew motors at a week long preseason training camp in Spain for nordic racers when those things first came out, that was extreme. But plenty of Japanese bikes have major failures too. Most track bikes that are listed for sale state that they have new oil after every single training day, to try to prevent this no doubt. Major horsepower has never been free.
 
Tippie said:
"Thousands of blown engines of all sorts back in the day are testimony enough.  A comparably rare thing these days." Happens reasonably often with modern bikes at races around here. There were eight (!!!!) Panigales that blew motors at a week long preseason training camp in Spain for nordic racers when those things first came out, that was extreme. But plenty of Japanese bikes have major failures too. Most track bikes that are listed for sale state that they have new oil after every single training day, to try to prevent this no doubt. Major horsepower has never been free.
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I know of one front-running team on 4-valve Ducatis that hasn't had mechanical issues over the past 3 seasons.  Kid rider is an ace, constantly harassing the established guys and taking 2nd place in his class championship 2019.  Guess it has a lot to do with bike preparation and mechanical sympathy on the part of the rider.  Reckon plenty riders consider they have bought a race bike when the pimply apprentice mechanic rolls their Panigale out the showroom.  Track prep is something else, as you well know.

Modern road bikes are now pushing out more power than race bikes from a decade ago, and that with 10000+km maintenance intervals.  Nothing short of awesome.  Not that I see the necessity or approve... ::)

Back to the blown engines; I was a big fan of the MV 750S back in the day.  Local dealer, who also took care of Ducati and Laverda, had about a dozen crankcases with fist-sized holes in them laying under his workbench (and that with maybe 80-100 of these bikes in the entire country!).  He didn't see anything abnormal about them throwing rods... put me off them very quickly.  Bevel twins had much the same attraction, once I realised how fickle and under-powered they really were, they lost a lot of their lure factor.

piet
 
ksoholm said:
No sir. No inertia engine dyno works without both disclosed and proprietary correction factors; they *all* measure the vehicle's ability to generate force at the rear wheel and then add correction factors. Dynojet dynos are likely the most widely used MC dynos around, and while not directly and accurately comparable dyno-to-dyno (Dynojet disagrees, says they are), they are a decent benchmark for bikes across the world.

Which brand dyno is your chart from?
Kristian
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All dyno's my machines have been on were made by Dynotec.

To my understanding, on this acceleration type dynos, you pull throttle until max  revs are reached and then pull clutch lever and the dyno measures the speed loss of the drum the rear-wheel is attached to and calculates the "loss" of the drive train. It then adds a calculated percentage to the calculated hp (a result out of a known weight and resistance of the drum, the time and the speed the drum reaches to within this time).

If you do NOT pull the clutch, there is nothing the dyno can measure as speed loss for calculating the drive train resistance. You can then either manually add a percentage to the values previously "measured" or just leave it as it is and you have real backwheel HP. This is what I am refering to as two different values.

On the Jota, the method above was used (no pulling of the clutch) to avoid issues with the clutch actuating system. Hence my understanding (and the explenation of the operator) that this is realy what the backwheel tire delivers to the road. He estimated the drive-train-loss with 12 - 15%, which then could have been added to the chart of 101HP coming to 112 - 115HP or - as we did - not, to keep the values comparable between the different runs (first runs before the exhaust modification were also done with no correction factors)

On the 1000 SFC, the Operator unfortunately allways pulled the clutch lever, which caused a big mess (3 times...) with the clutch actuating system (balls in the system welded the two rods together, the right side rod welded itself to the ball in the slave piston and that ball melted and sticked inside the piston so the piston started turning at clutch speed...  :o)
 
BTW: the 750 S (Zane) engines - at least the Formula ones - were a bit better in terms of HP. I know several that were actually measured almost exactly on the values the factory showed. One even was tuned with a Powercommander to over 105HP (out of 750 CCM), which is roughly 140 HP/liter.

Also keep in mind, please, that the V6 was also producing between 140 and 155HP out of 1000ccm, depending on the setup. OK - 4-valve head, water cooled etc., so a bit different to the triple engines...
 
"If you do NOT pull the clutch, there is nothing the dyno can measure"
Interesting Lothar. Our Dynotec place strictly forbids pulling in the clutch. You have to let it slow down and drop down gears until it is almost stopped.
 
they are wise to do so, however, there is no way to measure drive-train friction this way. I assume they simply use a percentage then to calculate from RWHP to ENGINE HP (or better: To Clutch HP).

to be completely exact though: what is measured is not HP but torque, HP is calculated out of that.
 
Laverdalothar said:
they are wise to do so, however, there is no way to measure drive-train friction this way. I assume they simply use a percentage then to calculate from RWHP to ENGINE HP (or better: To Clutch HP).

to be completely exact though: what is measured is not HP but torque, HP is calculated out of that.
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Is this Dynotec of Dynotec tuning fame? Their dynos do show higher figures than Dynojet dynos. Still, they must use a proprietary correction factor to calculate initial HP readings from the actual run, followed by another correction factor from transmission losses, in both instances the correction factors will be whatever Dynotec decided. Still, just as useful as any other brand of dyno for before-and-after modification testing. There is no point in trying to ascertain some precise crank shaft figure; no one even knows how most MC makers decide to rate their bikes.

I like my clutch slaves and throwout bearings far too much to subject them to 8K RPM clutch pulls ;)

Kristian
 
Crankshaft horsepower is not a particularly useful thing to know. It's rear wheel horsepower where the rubber meets the road that matters.

The only time it might be useful to measure power train losses is if you think there might be a problem somewhere in the transmission. But you can pretty much get a feel for that by turning the rear wheel by hand, either in neutral or in gear with the clutch pulled.
 
Yes, RWHP would be what would matter. However, what you normally get as a print out or a figure from a dyno run is a corrected figur that - by percentage, christal ball reading or just voodoo - takes the measured rear wheel torque, calculates it into HP and adds a correction factor to it to get to engine Power. No Bike vendor in the world tells you what the RWHP of your bike is, as they all want to claim the higher, engine power value!

So - here is the question: do you think Laverda claimed 85 RWHP or engine HP for a RGS? or 95 HP for a Corsa? I am pretty sure it was engine power and not RWHP - no matter where it was measured or how (and Laverda had an ENGINE dyno btw...).

If you put ANY standard Laverda Triple on an acceleration type dyno and do NOT add the correction values, you will see a Horse-power output of maybe 62 - 64HP (180? 3C, 3CL) or 75 (RGS) or 85 (1000 SFC/Corsa). It will just be roughly 10 - 15 % below the factory values. And that is REAL Rear wheel HP then. As soon as correction factors - measured or just entered - are used, you have a calculated engine power. That is my understanding of it and that is what two different operators told me on how the dynojet acceleration type dynos work.

So - if you want to compare achievements during tuning, you either need to make dyno runs before and after the tuning with the same correction values or compare engine power with engine power at least. It makes no sense to compare the factory engine power values with tuning achievements of RWHP.

 
Factory horsepower values are like pretty girls in the ads, a sales gimmick.
I prefer the girls.

Don't you have PS in Germany anyway?

Paul
 
Paul, the point is that many people think that if a bike is measured on the dyno, the outcome is RWHP. That is simply not true, as most operators add the correction factors and you end up with the higher value, wich is engine power. That makes things hard to compare when people claim "my bike produced 95 RWHP on the last dyno run". this can be true, but as said, in most cases the operator either just enters the correction value to compensate drive train losses or - if clutch is pulled - measures it and adds it to the measured result. The owner thinks it is RWHP, the truth is it is crank power, measured on a rear wheel dyno. as the difference is significant, at least I want to be precise on that to avoid comparing apples with pears. The next question is, what Horse Power it is... There seam to be SAE Horse Power, DIN Horse Power etc. etc.  What I refer to compares to Killowatt by factor 1,359. BHP (also refered to as SAE HP) has a different value (1,34xxx). See:



              Unit                  bhp          kW            PS
1 bhp (brake horsepower) 1            0,745700 1,01387
1 kW (Kilowatt)                  1,34102  1              1,35962
1 PS (Pferdest?rke)            0,986320  0,735499  1


and yes, we have PS. we also measure everything else (except for water tubes) in metric values
 
DIN PS/hp claims refer to power produced by the engine, IN THE CONDITION AND STATE IT IS FITTED TO THE VEHICLE, ie, all ancilliries hooked up and working, and ALL required legal equipment fitted.  This would include servo, vacuum and cooling pumps, A/C equipment, alternators, etc. in the case of cars.  DIN PS are measured at engine exit, ie, clutch.

Most other measuring methods do away with much of that, using only the engine in the most favourable of constellations to extract the maximum available.  In this case, alternators and pumps etc. are omitted, filters and other restrictions often optimised.

piet
 
sfcpiet said:
Most other measuring methods do away with much of that, using only the engine in the most favourable of constellations to extract the maximum available.  In this case, alternators and pumps etc. are omitted, filters and other restrictions often optimised.
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... and diesel NOx minimised.  :D

 
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