Genesis of the Jota: Part 1 - The Laverda 3CE

tom3c75

tom3c75

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Cape Town South Africa
Attached is an article by Dave Minton on the 3CE, taken from the December 1975 edition of 'Motorcyclist Illustrated'.    The 3CE, a performance enhanced version of the 3C, was developed by  Slater Laverda in the UK and was the forerunner of the Jota.

The images, taken from the Gallery, are not very clear.  I've therefore attached three PDF files (pages 1-2, pages 3-4, page 5), which are hopefully more readable. 

Tom

[Admin note: image URLs amended to full size versions - click to enlarge]

WP_Laverda3CEPage1.jpg

WP_Laverda3CEPage2.jpg

WP_Laverda3CEPage3.jpg

WP_Laverda3CEPage4.jpg

WP_Laverda3CEPage5.jpg


 

Attachments

Another great read from Dave Minton. Did he miss the bit about the high compression pistons?, or is it a fiction, hard to imagine just a bigger collector (replacing the 2" headers!!! into a 3/4" collector) and slightly bigger muffler inner diameter would give it 150mph+.
 
SFC yokes do not give you more trail .... they give you less. Another math problem.

Also has the 1976 instrument/handlebar mounts that apparently were not available in 1975.

It would be interesting to know the timelines of when they introduced the high compression pistons and the 4C cams.

Jim
 
Jim..AIRC the HC pistons and endurance racing camshafts were around in early 1976 from Laverda. I was in the USA and the Laverda importer (Yankee or Continental?) got them for me from Italy with a nice handwritten cam timing spec sheet too. The factory also sent a nice 3-1 racing open mega.

Parts were off the shelf for the importers. How early? I am sure the Dave Milton 3CE was built up with some hot rod internals but not acknowledged.
 
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Jim...My misspent youth working at the small town independent Porsche shop part time, going to school and spending all my extra money building club racing motorcycles. Started with a 250cc Ducati and then a Duc 750 Sport then the Laverda 3c..wonderful. I did not own a car. I rode an BMW R75/5 year round..nutts!

The Laverda importer supported me club racing on weekends, brand promotion. Parts and other bits at cost or sometimes free.

Still have the 3c.
 
Yes, definitely some figures have crept into the article that don't add up. Power increase required to go from 130mph to 150+ is way more than anyone on the planet could get by increasing exhaust collector and muffler dia and two teeth down on the rear sprocket. I'd hazard a guess that even the Jota (HC pistons, cams etc) would not reach that speed? The thing that troubled me most was how the bike was basically 'unsafe' at its highest speeds!! Horrendous description Dave Minton gives of that! I'd hate to experience it with the std yokes.
 
Piranha Brother 2 said:
Maybe on paper, but having ridden the same bikes with both, it doesn't feel like that.
Click to expand...

Standard yokes ..... increased trail ..... more stable.
SFC yokes ...... less trail ...... quicker steering.

Maybe you experienced both .... but got the experience mixed up ..... but then what do I know?

Jim
 
Without the sarcasm, this is a good subject and the offset/ kickback etc with triple clamps has been discussed before. I have clamps from Jota on both my SF, 20mm less offset and are parallel, works great and I far prefer it over the kicked back SF clamps which always felt a bit weird to me, feel is very individual. No Laverda from this period could be called quick steered (especially not an SFC), for the time they were all rock solid stable and also well steerable at high speeds. Dave Minton never claimed to be a top racer and all his reports I read were from the point of view of a street rider. Few street riders can be relaxed on the bike when they get way out of their comfort zone , which can cause all manner of handling problems.
 
helicopterjim said:
Standard yokes ..... increased trail ..... more stable.
SFC yokes ...... less trail ...... quicker steering.

Maybe you experienced both .... but got the experience mixed up ..... but then what do I know?

Jim
Click to expand...

You'd need to explain the physics of those non-parallel triple clamps before you could convince me that they should be more stable because they have more trail. Sorry Jim, but the weird angles involved just don't produce a more stable front end at high speed.
 
Piranha Brother 2 said:
You'd need to explain the physics of those non-parallel triple clamps before you could convince me that they should be more stable because they have more trail. Sorry Jim, but the weird angles involved just don't produce a more stable front end at high speed.
Click to expand...

Head angle and wheelbase also enters the equation.

The negative-raked yokes are a clever trick to increase trail without changing head angle or increasing wheel base, best of both worlds... sort of.  Less yoke off-set would achieve the same, but can cause steering/clearance problems at full lock, see bevel SS Ducs.

Quiz Fernando next time you meet him, he probably thought it up, or at least, he evaluated it.

piet
 
When I first read the bit about adding a cam and an exhaust and fitting the biggest main jet you could find and suddenly you had the fastest bike on earth that impressed me heaps. We all should know better now, it takes lots of finessing of these parts by experienced Laverda mechanics to get them working at there best.
 
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