Hierarchy of camshafts

Alzero

Alzero

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Is there a table that lists the various camshafts and their characteristics? I have Axtell’s in an otherwise stock RGS and was wondering how they fit in compared to the various A-series.
 
I think what is more meant is how the power/torque development is of each of the variants. There have been some diagrams on here comparing them, but I think they were more calculated than measured. Basically saying:

A11/A12-cams are more low end torque oriented than top end power (=> more for cruising); A12 is for lower emissions and has a bit less power

Axtel I would rank similar to the 4/C or P1-cams, maybe even between them. They are said to deliver more midrange torque than the A11 while providing a bit less very low-end torque. I have never had them on my bike though, so no first hand experience.

HTH
 
The way a cam performs will have so much to do with other factors: capacity, CR, exhaust system, carbs, valve sizes ... they're all going to have an impact on low, mid, high RPM. But it is true that different profiles used in an otherwise unchanged motor will have measurable differences (and not necessarily to the better) - bring on the dyno figures! And torque figures and curve shapes will have a much closer link to seat of the pants feel than outright HP.
 
piranha-bro2 said:
The way a cam performs will have so much to do with other factors: capacity, CR, exhaust system, carbs, valve sizes ... they're all going to have an impact on low, mid, high RPM. But it is true that different profiles used in an otherwise unchanged motor will have measurable differences (and not necessarily to the better) - bring on the dyno figures! And torque figures and curve shapes will have a much closer link to seat of the pants feel than outright HP.
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Correct. Plus a clever tuner can massage the shape of the torque curve by choosing to put the cams in on different lobe centers from those intended.
Any "hierarchy" can only be indicative of what can be expected if they're installed as specified.
 
They can have odd effects on measuring engine compression as well. One change affects another and visa versa.
 
Series 1 x 1200 engine, 7C Cams, 82mm bore, custom gas ported Ross Racing pistons, low tension rings, Carrillo conrods, PAC Alloy Dual valve springs, Kibblewhite Valves, lots of head porting work, 13.8:1 CR
Lightened crank, Kevlar clutch, strengthened bottom end, billet Mainshaft 4th gear, billet Output shaft with Outrigger bearing support
38mm Mikuni Flatslides, custom extended Inlet Manifolds, Redax ignition, Ignitech box, running 3 x Nology Pro-Fire coils
103 octane fuel with 3.8% oxygen content, custom 3-1 exhaust and lots more

Our best was 134.6hp but damned if I can find that chart, this Dyno pull only 131.16hp

Mule 131
 
Vince said:
It's the tuning that's so important. How many Dino runs to get the best result? Megabucks helps as well. https://www.ducati.ms/threads/doug-lofgren-f-g-genius.609697/
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we did 55 dyno pulls over a matter of weeks

did not cost that much in the end, Fred that owned the Dyno shop asked me where I was getting all my custom parts machined
when I told him that I had my own machine shop and was doing the majority of the machining myself he loaded me up with engine parts for his Pro-Stock Suzuki drag bike and I machined everything he needed for free, took about three days
After that we never paid for another Dyno session, he had two Dyno rooms and on every Tuesday his brother had the day off so we had the Dyno room to ourselves all day if we wanted it
worked out great
 
redax5 said:
at the time they were set at 104 degrees Inlet and 100 degrees Exhaust but have changed from that now
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I should think so too, lol.
I've been playing with lobe centers in 2V shallow hemi heads for around 40 years now.
And Suzuki 4V heads for longer than that.
Not many surprises left.
 
redax5 said:
Series 1 x 1200 engine, 7C Cams, 82mm bore, custom gas ported Ross Racing pistons, low tension rings, Carrillo conrods, PAC Alloy Dual valve springs, Kibblewhite Valves, lots of head porting work, 13.8:1 CR
Lightened crank, Kevlar clutch, strengthened bottom end, billet Mainshaft 4th gear, billet Output shaft with Outrigger bearing support
38mm Mikuni Flatslides, custom extended Inlet Manifolds, Redax ignition, Ignitech box, running 3 x Nology Pro-Fire coils
103 octane fuel with 3.8% oxygen content, custom 3-1 exhaust and lots more

Our best was 134.6hp but damned if I can find that chart, this Dyno pull only 131.16hp

Mule 131
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Are you running twin plug ignition? If so, what difference does it make?

cheers,
bazzee
 
bazzee said:
Are you running twin plug ignition? If so, what difference does it make?

cheers,
bazzee
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I don't believe there is any advantage in running a twin plug head on a Laverda triple
Being a Hemi style combustion chamber and with relatively low piston crown dome shape there is really no barrier to impede the flame front from completing full combustion of the Inlet charge
And that includes the pistons we have custom made that do have a significantly higher dome shape than say a standard Jota piston

Twin plug heads only really come into their own when you have very high domed pistons which then impede the combustion process
Or say something like a Top Fuel engine where they have something like 90% of the chamber at TDC full of fluid

We did actually weld up a 78 triple all alloy cylinder head few years ago that had cracks all through it up to the spark plug seat with the intention of turning it into a twin plug head using 2 x 10mm plugs each side of the chamber
Also welded up the floor of both the Inlet and Exhaust ports with the intention of porting it to match our race heads but have not progressed on it any further, been concentrating on other items on the bikes to lower our lap records

I may be wrong though
 
I have been told that twin plugs make sense at dia of 90 mm and more, but also your argument of the shape of the dome I can understand. But could be worse a experiment, twin plugs need less advance ignirion and maybe archive higher revs and top speed???? 🤷‍♂️
 
andre g said:
I have been told that twin plugs make sense at dia of 90 mm and more, but also your argument of the shape of the dome I can understand. But could be worse a experiment, twin plugs need less advance ignirion and maybe archive higher revs and top speed???? 🤷‍♂️
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With effectively no squish to promote fast burning in a Laverda head It might well pay to try twin plugs.
 
30 years ago I build a Ducati 650 Pantah with twinspark with a Moto Witt ignition
It was easy to change ignition time from twinspark to standaard.
In 5 minutes work I could try twin and standaard.
The main difference was bottompower not more power at high revs.
On the road very nice , no advance on the racetrack.
 
I was at the Dino when Doug Home ran his twin plug bike and it didn't achieve a big number, that was a bit of a shock at the time. From memory mid to high 80s. Years later Marty acquired it and I had a ride, it was impressive. I didn't go Hog Wild on it, it wasn't my bike. Really nice suspension and handling with strong power, surprisingly strong right off idle but not earth shateringly strong. BTW I still regret turning Steve B down on riding his 100hp fuel-injected Blue RGA, it was such a nice bike and crashing it would have been a crime but it would have given me a baseline on what a 100hp Laverda feels like. Quote from Marty, WOW what a bike.
 
100 plus HP 200kg Motodd running Axtell cams is pretty exciting as well. The fastest triple I've ever ridden.
I did get to ride Battos RGA once apon a time.
Very nicely set up.
Can't remember if it had the FI fitted then
 
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