the hobbler said:

Found it! The u-tube to watch is:--"Kawasaki Z1-1396cc Super six 6 cylinder engine first start" When you have watched this film, watch how he casually describes how he he built his "V12" bike engine--the guy is plain BRILLIANT

Click to expand...

Did you see how he extended and retimed the camshafts for the Super Six?

They were literally cut into cylinder sections with an angle grinder on his back lawn, then turned, assembled and timed in the lathe using old piston gudgeon pins to align the joints. Finally TIG welded using a special motor controller to turn the shaft at 1 rpm. Finally trued-up in true Allen style with a copper hammer and backing weight.

He did something similar with a Yamaha 16 valve FZR250R (limited to 45bhp at 14,500 rpm).
https://www.youtube.com/watch?v=pxsRHqPF5os

His Honda SS100 is a work of art. A V-twin made using two SS50 moped cylinders on a modified crank.

fiat500 said:

I'm going to blaspheme here....I like the look of the Citroen 2CV engine.
I take my hat off, both to Ian and the designer of the 2CV engine.

Click to expand...

Well, I for one would like to either reassure you no blasphemy committed, or to join you in the blasphemous corner

I covered many happy miles in several 602cc 2cvs and can confirm they're perfectly happy to have the throttle pinned open for hours on end.

Mountain passes in the Cevennes were never a problem, just noisy and sometimes fume-y. Might be a good idea to have that engine in the back, after all...

I agree, Walter Becchia (designer of the 2cv flat twin) is one of those great engineers who seem to get forgotten. He was Italian and started out at FIAT, so maybe no blasphemy caused after all

As I understand, the 2cv engine was based on a BMW motorcycle engine design, and is one of only two production engines to have a trebling of power output during its lifetime - from 12bhp all the way to a heady 36! The other was also an air-cooled boxer, but a bit more powerful...

Interesting that you say that Walter Beccia was Italian and started his career at Fiat. I have heard that one of the original prototype engines for the 500 was---a boxer twin! I have also heard, to tie in with that story, that the Steyr Puch engine was a Fiat development engine, but whetjher that was one of those rumours that become 'fact' over time, I do not know.

the hobbler said:

Interesting that you say that Walter Beccia was Italian and started his career at Fiat. I have heard that one of the original prototype engines for the 500 was---a boxer twin! I have also heard, to tie in with that story, that the Steyr Puch engine was a Fiat development engine, but whetjher that was one of those rumours that become 'fact' over time, I do not know.

Click to expand...

Fiat do a fair few joint projects so could be right about the flat twin.
e.g. The 1.9 and 2.4 diesels were a Fiat/VW project. Common rail diesel injection was also a Fiat project. They sold it to Bosch during one go their financial dips.

the hobbler said:

I have heard that one of the original prototype engines for the 500 was---a boxer twin!

Click to expand...

"......outlined are the more important designs of experimental engines studied as substitutes for the ‘500’ model: a transversal four-cylinder engine, with overhead camshaft, built in 1945, for a front-wheel drive prototype; an air-cooled, two-cylinder in-line engine, mounted transversally, for a rear-wheel drive prototype; an opposed two-cylinder engine, with longitudinal axis, in replacement of the previous unit; a two-cylinder in-line engine with longitudinal axis, finally chosen for the ‘New 500’ model introduced in May 1957."


From:

Paper 6: The Engines of the Smaller Fiat Cars
Dr.Ing. Dante Giacosa
First Published June 1, 1963 Research Article
https://doi.org/10.1243/PIME_CONF_1963_178_138_02

https://journals.sagepub.com/doi/10.1243/PIME_CONF_1963_178_138_02

Very interesting Peter---any idea where I can obtain a copy of that paper?

the hobbler said:

Very interesting Peter---any idea where I can obtain a copy of that paper?

Click to expand...

Sorry Tom; unfortunately, as with a lot of academic studies, it costs a bit even to read this report. It's $40 direct from the website; I'll not be buying it.

Thank you Peter. However, the snippet of information you gave as to the 'development' engines was very interesting, and proved that the story I had heard regarding a 'boxer' engine as being one of the development engines was true.

fiat500 said:

Sorry Tom; unfortunately, as with a lot of academic studies, it costs a bit even to read this report. It's $40 direct from the website; I'll not be buying it.

Click to expand...

Maybe a student friend can get access to it.