NorVin . Norton Vincent .

Triton Thrasher · Oct 5, 2012

J.A.W. said:
British rag 'The Motor Cycle' [May 20 `37], tested this new 1000cc OHV V-twin;
"Its acceleration is without exaggeration colossal...in any ratio the terrific surge of power is breath-taking...just as the acceleration is remarkable up to 50 mph, so it is above this speed , up to 80mph & more.
There is an indescribable thrill about riding this large machine along a wide, straight & deserted main road. Sitting bolt upright in armchair comfort, one can almost immediately command any speed up to 85mph on the level.
The big machine can be swung `round bends at extraordinary angles, while bumps are ignored..."

What could this marvelous machine be?
An A series HRD? Actually no, its an H-D , knucklehead..

We didn't think it was an 85mph Rapide, you know.

Matt Spencer · Oct 5, 2012

I want MORE power . :wink:

Going Fishing , at the Pier .

J.A.W. · Oct 7, 2012

Anyone got a series A Rapide test -max speed [sitting upright] to quote?

worntorn · Oct 7, 2012

I have two friends with series A Rapides, I could ask them. One A rap is a real one, the other is a creation made in a basement full of machine tools.
The creation was built by Dan Smith. At the moment he is building a replica of the Velo "Roarer", the supercharged racer restored and owned by Ivan Rhodes.

The top speed normally listed for these prewar twins is 110 mph. Ginger Wood did some mods to an A Rap back in the thirties and clocked a low 11 second quarter mile. Ill see if I can find the info.

Glen

J.A.W. · Oct 12, 2012

Hey Glen, your buddy Dan Smith has a side bar in a Motorcycle Classics [Sept/Oct `12] article on an A-series HRD Rapide.
So - only `bout 80 built, makes for a close rivalry with the Crocker really, including performance as recorded, both ton-plus capable.
Interestingly, I recently saw an expensive pedal bike that featured the 'brilliant' idea of a seat sprung in the support tube, owner was crestfallen when I told him it was used by H-D back in the `30s..

Bernhard · Oct 13, 2012

J.A.W. said:
Hey Glen, your buddy Dan Smith has a side bar in a Motorcycle Classics [Sept/Oct `12] article on an A-series HRD Rapide.
So - only `bout 80 built, makes for a close rivalry with the Crocker really, including performance as recorded, both ton-plus capable.
Interestingly, I recently saw an expensive pedal bike that featured the 'brilliant' idea of a seat sprung in the support tube, owner was crestfallen when I told him it was used by H-D back in the `30s..

Not for the first time either; Yamaha paid a sum of money in the 1970s for the rights to a monoshock rear end. Imagine their surprise and dismay a when someone rode a 1950s Vincent V twin into the race paddock with it already fitted :!: :roll:

Rohan · Oct 13, 2012

Monoshock rear suspension is almost as old as motorcycling itself ?
And, the ASL of 1910 had quite a sophisticated pneumatic suspension system to go with it.

Good coverage from Pete
http://occhiolungo.wordpress.com/2012/0 ... uspension/

If Yamaha paid money for anything, 'due diligence' must have been sadly lacking !!
I'd think it more likely they'd found the patents had expired or lapsed...

J.A.W. · Oct 14, 2012

Vincent rear end used twin shocks, Yamaha system used a single[mono] De Carbon spring damper unit, did you mean 'cantilever' type swing arm?
Like-wise 'upside down' front forks were used on many an old machine [Guzzi for one], prior to being 're-invented ', & if you have a look at the Nazi era G.P. 500 BMW, the frame, forward of the plunger rear end is very 'featherbed' like,. Zundapps too, of that period -also feature 'perimeter frame' chassis...

worntorn · Oct 14, 2012

The Vincent Series D (last series of bikes built) used a monoshock rear suspension system. Ive borrowed heavily from the D Vincent design for the back end of the Glenli, but added progressive geometry into the mix. The D Vincent rear suspension was strictly linear.

Of interest, Yamaha hired an aging ex-Vincent Engineer to consult on the design of their monoshock system.

Glen

J.A.W. · Oct 14, 2012

Interesting yes- thanks Glen, I stand corrected .
Yamaha also had a good look at the NVT prototypes -their 1st road bike [LC] cantilever looks VERY like the BSA MC1 250 G.P. bike built by Doug Hele in the `50s...

Rohan · Oct 14, 2012

Bert Hopwood would not be amused by you denying him half the credit for the MC1.
Not that it came to much eventually, unfortunately....

acotrel · Oct 15, 2012

Have you seen this ? It is a 1400cc replica built by Ken Horner from Melbourne, Australia. It is unbeatable in historic racing in its class :
I believe it won the BOTT at Daytona last year ?

acotrel · Oct 15, 2012

Here is the sidecar version of the Irving VIncent:

J.A.W. · Oct 15, 2012

Yes, amazing what can be done, if you have the resources to back up the intent.
Say Aco, what is that odd BSA looking V-twin in the background of the sidehack pic?

acotrel · Oct 16, 2012

The V - twin BSA was built by Doug Fraser of Frankston, south east of Melbourne Australia. There are write-ups about it in Jim Scaysbrook's 'Old Bike' magazine published out of Sydney. Apparently the bike performs quite well. Doug is an old historic racer from the 70s, and has a comprehensive engineering workshop. If you want a copy of the magazine, I will post Jim's email address and you can negotiate with him directly. I can also put you in touch with Doug.

Rohan · Oct 16, 2012

A pair of B33 top ends on a custom crankcase.
Think he called it a B66.

BSA had a long tradition of building v-twins prewar, some of them were renowned taxi sidecar haulers....

Rohan · Oct 16, 2012

P.S. With that disk front end, not sure thats the same bike though...

Triton Thrasher · Oct 16, 2012

worntorn said:
Of interest, Yamaha hired an aging ex-Vincent Engineer to consult on the design of their monoshock system.

Glen

So they weren't really all that surprised or dismayed.

Not for the first time either; Yamaha paid a sum of money in the 1970s for the rights to a monoshock rear end. Imagine their surprise and dismay a when someone rode a 1950s Vincent V twin into the race paddock with it already fitted

acotrel · Oct 17, 2012

The only differe nce is that the Japanese 'did it right first time' ! It is a characteristic of their culture that all Europeans need to learn.

worntorn · Oct 17, 2012

I thought Phil Vincent did a pretty good job with his first design (patented) of triangulated rear suspension in 1926.
There were improvements along the way tho, such as hydraulic dampening. There were no Koni or Ohlins products to bolt on, Vincent had to design and make his own front and rear dampeners or shocks. I give a lot of credit to the original thinking that creates these designs, less so to the copiers. It is the freethinking original designers who really make progress, the copiers just polish the edges, but we loved the polished products.
Without the original idea there would be nothing to copy or improve upon.

Back in the twenties the British held more patents than any country on earth. Amazing for such a small poplulation. Today the US holds the most, but it is surprising how many of those US patents have been purchased from British inventors. They are a nation of freethinkers and from that many great things have come.

Copying vs inventing is like the diference between writing and performing and original song vs. doing a cover. But to give credit where due, the Japanese tend to do very good covers.

Glen