Laverda Jota camshaft differences

I can only comment on the bikes I met during the "free" sessions in SPA the past two years. There were only some real original bikes (nor was mine...) and many, partly to an extreme, modified ones.

With most of the 70's - even in modified tune - it was very easy to keep up and overtake, especially on the brakes (and I am not good on these...). Remember a situation where a Bol D'Or Honda was running up the long straight after the hill that follows Eau Rouge. At the end, there is a right - left turn, for which you have to brake down to 3rd gear at least (coming from full throttle). We were close up at the end of that hill, me on the inner side, him on the outer. He was looking over to me, I was looking over to him, both obviously thinking "Common, YOU need to be first on the brakes!". At the 150 Meter sign, I thought: "Shit - he is brave!" and just after I pulled the brakes and shifted down, just to see him recognizing he just passed the 100 Meter sign 1/2 second later. The heavy braking he started caused the bike to wave and wave more and more to a point, where he was still ahead of me but still to fast to take the curve due to a bad suspension setup. Fortunately, he decided simply to keep on moving and braking and took the "exit" straight out of the first curve, luckily on both wheels...

Deep breather followed I assume on his side, I simply took the curve and thought "Man - next time you take the brakes at around 125 Meters, that was really way to early..."  :D
 
All Jota's sold in Belgium also had the full Jota specs (4C, high compression, typical exhaust).
As good Italians the Bevilacqua brothers (Enzo company) of course supplied all bikes with homologation conformity papers but in reality, well ...  ;)
Well, fortunately for us Belgians...
 
I just bought a set of A12 cams from France. I'm going to use the sprockets to drill them full of Vernier holes, and the cams themselves will be used as blanks for Megacycle's F1 grind. One of the very few Laverda performance upgrades available in North America.
Scott Potter is heavily involved in this process, in case anyone else is interested.

Ken
 
Grinding an F1 profile onto an A12 core is maybe not possible Ken but if your grinder can manage it you are going to require enormous custom made shims to make up for the material lost from the base circle whilst re-shaping the cams nose profile for the correct lift and duration, I have done it on an A11 core where just over 2mm is lost of the base circle diameter, It will require even more material to be removed from an A12, possibly more than the cam can afford.


    Keith.
 
Hi Keith,

have you ever done a dyno-run on the same bike, same day, same dyno with 4/C and F1 Profiles on a 180?? Or any other comparable runs?

Would be much interested in a set if they deliver better running of the engine and more power/torque... Remember, I have a spare Jota fairing...  :D
 
I've done A11 V F1.  F1 gives nice bulge in the midrange, but my bike was restricted (airbox and/or head) so wasn't able to make the most of the top end. 4 to 6500 has a nice torque curve with the F1s.

F1dyno.jpg
 
Hi Reggie,

thanks, that shows nicely that the F1 do offer an increase over the full rev range, great to see!

I had the  very same drop btw in the curve between 3.500 and 4.500 as - I think - almost all bikes do. Got rid of it only with the 3-2 collector, special made for my bike. Now have a very clean curve!

Same on the SFC 1000. God rid of the (even more significant...) drop only with the SR-Racing 3-1 Exhaust.

Seams the collector - no matter which one btw... - is the problem here...
 
And there was surely more to come- on the dyno the mixture was fine but I think it could have been leaned off a bit more, the bike always felt stronger when it was cold, and pod filters would have been a useful step forward too I think.  Maybe the new owner (wherever he is) has done that.  Or more likely painted it orange and silver...yawn.

On the road that drop was hardly noticable so I never spent much time chasing around trying to fix it.
 
keith, i know you aren't fond of the idea
but megacycle welds up the cores
grinds the profile then hardfaces the lobes
end result is a cam with correct base circle
all the lobes are exactly the same
with correct cyl to cyl timing events
(they use a Landis CL grinder)
current std lav grinds from megacycle are A11, 4C, 5C, 7C, F1
additionally they can put any profile from their library on a Lav core (twin or triple)
when i can put my hands on an early axtell set i'll have new masters made at megacycle

the original axtells (named for the designer c.r. axtell) from lance were regrinds on 4C and 7C cores
base circles were very close to stock as the big lobes had a lot of meat for the new profile
the current axtells from wolfgang tend to be regrinds on A11 or F1 cores
these have a reduced base circle to fit the profile within the existing lobe shape
these are a viable alternative to the cost of replacing sunk seats

fwiw the axtell profile was designed for the american rider
nice fat midrange but falls off on the top end

i like the F1 power delivery in both engines and prefer it to the axtell
though i'd be tempted to use the ax in a std 1200


cheers,
scott

 
Hi Scott,
I had a Axtell profile reground on an old set of 4c. One thing I noticed, I'd just had the head done, valves, guides, seats, and refitted the "new" head with my original A11s. Guy did the head fucked it up as I only ended up with 1.5-1.8mm shims!! In the mean time I was waiting for my Axtell grind cams to be finished. 150 kays later and the #1 ex valve nipped up resulting in bent valves, trashed bucket and cam lobe. 2 new valves later I installed the Axtells and was amazed I'd got my clearance back again 2.7-3.2mm. :)
Also interestring, the engineer who just finished my head notice the ex guide on #1 had a crack in it! Probably been there for 55000 kays after dropping that valve!! So a new set of guides were installed.
Got lashings of ceramic coatings too as well as the 81mm ross pistons. Decided I really need to do the little ends now so another delay in reassembly. Being 420km away from laverda civilization these jobs take time!!!
Axtels do have fantastic mid range. At first it seemed like I had a close ratio g/box as I was getting through the gears real quick!!
When I got some spare $$ I'll send you my A11s for a F1 grind.
 
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