Author Topic: LAVERDA Triple 4-valve head  (Read 1855 times)

Offline Laverdalothar

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Re: LAVERDA Triple 4-valve head
« Reply #30 on: August 15, 2019, 10:53 »
Lothar, rule of the thumbs says that the reason for a 4-valve head is the higher charge and resulting higher
peak power. If you optimize an engine for a higher charge, this is usually at the expense of the lower and
middle speed range (if you leave variable control times, etc. times out).

....

jm2c
Jo

Hi Jo, I think to remember you have an engineering background, which I respect, please. I suppose the original design is - compared to todays knowledge and possibilities - so inefficiant, that re-designing it completely will improve torque and power in all rev-ranges.

I have made my experiances which we can discuss offline if you like. I broke many of these "rules of thumb" to the surprise of a lot of people, me included.
« Last Edit: August 15, 2019, 11:00 by Laverdalothar »
750 SF(0) 1971 #9934 *sold*
1000 SFC Classic 1989 #3367 *sold*
1000 SFC 1985 #2934 currently under restoration
1000 SFC Preproduction bike 1985 #0001 *sold*
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Offline hochkoenig

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Re: LAVERDA Triple 4-valve head
« Reply #31 on: August 15, 2019, 11:00 »

Since Gijs himself is not starting this threat, it shows how Rational Humble and Realistic he Works. The 4V Head is for Racing only, he works with a motoGP Man to make shure not going too much wrong here. Anyway, his Racing Sucsess and Experience should keep us little Quiet in smart Talking...

Offline Laverdalothar

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Re: LAVERDA Triple 4-valve head
« Reply #32 on: August 15, 2019, 11:08 »
I can't see anything wrong with sharing thoughts and oppinions on these modifications. Gijs has made it public already (Facebook, having the parts on display etc.), so I guess it would not really surprise him if people talk about it...

It's a free world and everyone can have a different view. Many things of what I did or asked professionals to do made experianced people shake and/or scratch their heads. I did it for me and my personal fun and learning and it was a good experiance.

Gijs indead has a great experiance in racing and if he has a GP-experianced person to help him, I trust it will come out extremely powerfull at the end. Let's not forget, time moved on 50+ years since this engine was designed. I would be shocked to the bones if someone could proof me there would be nothing to improve anymore on these engines... ;D
750 SF(0) 1971 #9934 *sold*
1000 SFC Classic 1989 #3367 *sold*
1000 SFC 1985 #2934 currently under restoration
1000 SFC Preproduction bike 1985 #0001 *sold*
1200 Jota 1981 #7474
750 S-Formula 2000 #1602
1000 Motoplast - currently under construction

Online Vince

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Re: LAVERDA Triple 4-valve head
« Reply #33 on: August 15, 2019, 11:42 »
So what's the point of being here if you don't express an opinion. Anyone producing anything as important as a head deserves full respect and an excited chatfest from the peanut gallery. If only championship-winning builders can comment it will be a short conversation.

Offline Jo

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Re: LAVERDA Triple 4-valve head
« Reply #34 on: August 15, 2019, 12:35 »
When you say that he is developing this head primarily for racing, the question arises for me how that is in terms
of regulatory compliance. For example, I know Gijs' missions in the 'Europen Classic Series' - as far as I know, the
engine there in the key data must correspond to the historical series counterpart. Which race series allow such a
modified engine according to regulations?

I admire Gijs work absolutely! The thoughts I expressed were not intended to criticize or question his work.

Cheers
Jo
Take people as they are - there aren't any others.

My Laverda pictures:  https://www.flickr.com/photos/italobikes-v2jo/albums/72157690026363615

Offline hochkoenig

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Re: LAVERDA Triple 4-valve head
« Reply #35 on: August 16, 2019, 10:04 »
When you say that he is developing this head primarily for racing, the question arises for me how that is in terms
of regulatory compliance. For example, I know Gijs' missions in the 'Europen Classic Series' - as far as I know, the
engine there in the key data must correspond to the historical series counterpart. Which race series allow such a
modified engine according to regulations?

I admire Gijs work absolutely! The thoughts I expressed were not intended to criticize or question his work.

Cheers
Jo

I don´t know this, must be the Same for Guzzi 4V, TR1, Britten...

Offline Tippie

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Re: LAVERDA Triple 4-valve head
« Reply #36 on: August 16, 2019, 11:18 »
If the Euro classic endurance series is like it used to be back in the day, it used to have classes for anything goes (within reason I guess), hence things like Nessie and Eric Offenstadt´s creations. Pretty sure motors could be innovated too. Would be interested to see the results of his work in action.
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Offline Grant

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Re: LAVERDA Triple 4-valve head
« Reply #37 on: August 16, 2019, 11:55 »
Maybe it's a silhouette class, where externally thing have to look standard but inside anything goes, like the modern NIkasil barrels on Guzzis with the square fins turned down to round to mimic the early Guzzi barrel appearance.
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Offline Tippie

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Re: LAVERDA Triple 4-valve head
« Reply #38 on: August 16, 2019, 12:42 »
Just the barrels LOL. Whole bloody ´96 1100 Sport engine in the up to ´79 class here and they don't even bother rounding the fins off any more. Would be a very depleted field without them though. My 750 SF2 beats some of them regardless.
The two valve Suzuki GS motors are the choice here even when the 4 valver can be used, more power etc, say the punters.
SF2 17483 (race)
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Offline Laverdalothar

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Re: LAVERDA Triple 4-valve head
« Reply #39 on: August 16, 2019, 12:50 »
Not sure where Gijs and his team participate, but if you look at the 4 hours of SPA during the Bikers Classics, Dynotec takes regularely part with their "Guzzilla" which I think is also a 4-valve head conversion... Not talking about all the Japs bikes that are massively modified... Pretty sure they simply don't care as long as all the bolts are secured and the catch tank is installed...
750 SF(0) 1971 #9934 *sold*
1000 SFC Classic 1989 #3367 *sold*
1000 SFC 1985 #2934 currently under restoration
1000 SFC Preproduction bike 1985 #0001 *sold*
1200 Jota 1981 #7474
750 S-Formula 2000 #1602
1000 Motoplast - currently under construction

Offline Jo

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Re: LAVERDA Triple 4-valve head
« Reply #40 on: August 16, 2019, 13:12 »
I've browsed a bit and found the rules of the European Classic Series:     Rules

2.2. Engine
o   For the engine, particularities as per the mass-produced motorcycles need to be retained: such as number of cylinders, number of gear ratios, number of camshaft etc.
o   The engine sump housing has to comply with the original. However internal modifications are allowed.
o   The crankshaft stroke is free. The cylinder bore is free.
o   The preparation of the cylinder head is free as long as the camshaft and valve numbers remain the same as the original. However, the cylinder head must correspond to the engine’s original model.

Means, using kind of such a modified head in this series would bear the risk being disqualified. Hard to imagine, that someone who is seriously involved in such a racing series would hazard the consequences for this …

For racing series, where the regulations allow more freedom, such a cylinder head could of course be of interest.

Cheers
Jo

Take people as they are - there aren't any others.

My Laverda pictures:  https://www.flickr.com/photos/italobikes-v2jo/albums/72157690026363615

Offline andre g

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Re: LAVERDA Triple 4-valve head
« Reply #41 on: August 16, 2019, 16:30 »
Hi,
maybe Gijs will use the 4 V head for other races than European Classics. As far as I know him he always tries to be very close to the original. I.e. he does not turn the brake calipers backwards and his argument to use a 120° crankshaft is that Laverda also used it in the 70th, spoke wheels and small tires...

Anyway, in may opinion it is a really outstanding engineering work so far and some financial invest, I really admire this development and I would like to see it running and would like to know the power which it will develop- but he did not tell from his other race bikes, maybe it will be a secret.

We have no chance than waiting for further news.

Andre

Offline Laverdalothar

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Re: LAVERDA Triple 4-valve head
« Reply #42 on: August 17, 2019, 09:12 »
Fully agree with Andre.

It would also not surprise me if he makes 2 engines for each bike, one with 2-valve and one with 4 valve and exchanges them according to the race class he is participating in.

and then - there is the fun part of developing something no one has ever done before. Cor did that with the rebuild of the 2 V6 and even re-designing of many of the parts (many parts if not all of the gear box f.e.), Gijs now creates maybe the most powerful 1000 ccm Laverda 3-cylinder engine ever built. Can't wait to see his riders slap the Kawa's and Honda's necks...  ;D A lot of development has gone into it already and a lot will still.

And let's not forget Red's brilliant work on engine power for the road and for racing!

We are blessed to have such talented and motivated people in our scene that keep the development on. Just great, a big Thanks to these guys and our suppliers for making the afford to keep our bikes running!
750 SF(0) 1971 #9934 *sold*
1000 SFC Classic 1989 #3367 *sold*
1000 SFC 1985 #2934 currently under restoration
1000 SFC Preproduction bike 1985 #0001 *sold*
1200 Jota 1981 #7474
750 S-Formula 2000 #1602
1000 Motoplast - currently under construction