Purity of design...

xbacksideslider · Nov 22, 2019

Going to how fast a Vincent can be - back in the 70's I had a friend, Greg Duvall, who bought/tuned a Norvin built by Dave Furst (First?) here in Los Angeles. Gorgeous bike, built to be fast - twin Lightning heads, Amal GPs with remote float with megaphones, IIRC. British racing green, Cerianis, and a Munch Mammoth 4 shoe brake.

We had a standing Sunday morning race than ran up the hill in Griffith Park and Greg always out accelerated everything - Nortons, Tridents, 750 Hondas, 500 Kawis. Then one morning, this is first half of the '70's, a local two stroke tuner and Park rider, Gary Schumake, showed up on his new 750 Kawasaki with chambers he'd built for it. Ooooh, the race was on. To get a good view, I made sure that I got off in third place on my Commando. Coming out of those uphill corners, that Vincent just killed the Kawi, AND it's wide ratios and wide power band maintained the murder right through to the end of the straights. Only later that day, when our Sunday ride got out of the Park and onto the long straight line national forest roads at well over 100 would the Kawi's close ratio peakiness close on that Vincent, but by then we were all running out of ratio. Great sounds that day.

Greg sold that Norvin to AMA superbike builder/master machinist Tom Farrell; Tom had plans for it but it sat in his shop for years; I lost touch and Tom and that bike disappeared. If I could get it today, I'd trade all my bikes and cars for it.

ericg · Nov 26, 2019

desmo said:
iirc the gearbox was very similar to the boxes used on Panthers only the mainshaft was slightly different

Huh!? Did you ever see a Vincent twin in the flesh?

acotrel · Dec 6, 2019

I think a good Manx would cream any Vincent on a reasonably tight circuit. I love Godet's bikes - if you wound one out on a big circuit, it would be really flying, but the weight of it might make it difficult to stop safely. Many years ago, I watched Tom Phillis beat Arthur Pimm at Phillip Island with a 500cc Manx, while Pimm's bike was a Norvin of 1000cc, and the combination of bike and rider was probably as good as Vincents ever get.

acotrel · Dec 6, 2019

xbacksideslider said:
Going to how fast a Vincent can be - back in the 70's I had a friend, Greg Duvall, who bought/tuned a Norvin built by Dave Furst (First?) here in Los Angeles. Gorgeous bike, built to be fast - twin Lightning heads, Amal GPs with remote float with megaphones, IIRC. British racing green, Cerianis, and a Munch Mammoth 4 shoe brake.

We had a standing Sunday morning race than ran up the hill in Griffith Park and Greg always out accelerated everything - Nortons, Tridents, 750 Hondas, 500 Kawis. Then one morning, this is first half of the '70's, a local two stroke tuner and Park rider, Gary Schumake, showed up on his new 750 Kawasaki with chambers he'd built for it. Ooooh, the race was on. To get a good view, I made sure that I got off in third place on my Commando. Coming out of those uphill corners, that Vincent just killed the Kawi, AND it's wide ratios and wide power band maintained the murder right through to the end of the straights. Only later that day, when our Sunday ride got out of the Park and onto the long straight line national forest roads at well over 100 would the Kawi's close ratio peakiness close on that Vincent, but by then we were all running out of ratio. Great sounds that day.

Greg sold that Norvin to AMA superbike builder/master machinist Tom Farrell; Tom had plans for it but it sat in his shop for years; I lost touch and Tom and that bike disappeared. If I could get it today, I'd trade all my bikes and cars for it.

I once rode a friend's 650 Triton at Calder Raceway and easily beat one of the faster guys who was riding an H2 Kawasaki which was the full bit. 750cc two-strokes tend to tie themselves up in knots. It is no good having tons of power, if you cannot get it onto the ground.
When you ride any featherbed bike, it always feels very big - with a Vincent motor, it is probably too much. I think Godet's bikes are Eglis. I have ridden three bikes around Calder - my 500cc Triton, my friend's 650cc Triton and a genuine 500cc short stroke Manx - the Manx is the fastest, simply because it handles and gets the power down properly. In Australia, we have several guys racing Norvins - I have a bit of experience and a Norvin is not something I would want to race.

acotrel · Dec 6, 2019

One thing you have mentioned was the wide ratio gearbox in a Vincent. Close ratios are always faster. The problem is that with a road bike, you don't usually ride them in the way that needs close ratio gearboxes.

acotrel · Dec 6, 2019

ttps://www.youtube.com/watch?v=1c5TU3Dwodo

Triton Thrasher · Dec 6, 2019

desmo said:
iirc the gearbox was very similar to the boxes used on Panthers only the mainshaft was slightly different

The pre-War Series A Rapide and the 500 singles had a Burman gearbox which must have been pretty similar to contemporary Panther, Matchless, AJS, Ariel, God knows what else.

worntorn · Dec 6, 2019

Triton Thrasher said:
The pre-War Series A Rapide and the 500 singles had a Burman gearbox which must have been pretty similar to contemporary Panther, Matchless, AJS, Ariel, God knows what else.

According to Desmo, the fellow who has been busy telling us how awful Vincents are, it was the gearbox of the postwar Vincent he was referring to.
There were about 11,000 post war bikes built and just about 70 prewar A Rapides.
Those few prewar twins used Burman transmissions which weren't up to the power output of a litre V twin, so Irving designed his own very sturdy unit for the postwar twins. I think of those prewar A twins as a prototype for the Vincent twin. During WW2, Irving and Vincent redesigned the entire bike to improve reliability and durability.

Glen

ericg · Dec 7, 2019

acotrel said:
I think a good Manx would cream any Vincent on a reasonably tight circuit. I love Godet's bikes - if you wound one out on a big circuit, it would be really flying, but the weight of it might make it difficult to stop safely. Many years ago, I watched Tom Phillis beat Arthur Pimm at Phillip Island with a 500cc Manx, while Pimm's bike was a Norvin of 1000cc, and the combination of bike and rider was probably as good as Vincents ever get.

Manxes are OHC machines specifically designed for racing! So no surprise that they are very good at that! Vincents are only road machines after all even though the Horner brothers built a Rapide with standard cycle parts and an engine tuned to about 95hp (with Monobloc carbs!) that demolished modern Manxes and G50's at Goodwood festival of speed two or three years ago.
And here is a Norvin vs Triton video:
watch
Not very good quality but interesting.

desmo · Dec 9, 2019

ericg said:
Huh!? Did you ever see a Vincent twin in the flesh?

yes but usualy in boxes or should i say casket ,decomposing

Fast Eddie · Dec 10, 2019

ericg said:
Manxes are OHC machines specifically designed for racing! So no surprise that they are very good at that! Vincents are only road machines after all even though the Horner brothers built a Rapide with standard cycle parts and an engine tuned to about 95hp (with Monobloc carbs!) that demolished modern Manxes and G50's at Goodwood festival of speed two or three years ago.
And here is a Norvin vs Triton video:
watch
Not very good quality but interesting.

It is a compliment to the Vincent that we even try and compare it to a Manx.

The Vincent was built as the pinnacle of luxurious, long lasting, mile eating road bike for the very well heeled.

The Manx Norton was a factory Grand Prix bike!

At what other point in time would anyone consider pitting a top of the range tourer against GP / Moto GP bike ??

ericg · Dec 10, 2019

desmo said:
yes but usualy in boxes or should i say casket ,decomposing

OK, now I understand your ignoring!

worntorn · Dec 10, 2019

Try riding a Manx two up plus luggage pulling up some 5 mile long mountain pass.
Or just try riding a Manx two up.
Starting off in town stoplight to stoplight would be interesting
Actually, even solo you would not enjoy riding a Manx on the road.
It's been done and they make a horrible road bike
Great race bike though.

Glen

Fast Eddie · Dec 10, 2019

Exactly Glen!

Folk are often keen to compare a Vincent to a Manx as race bikes... never vice versa. Probably cos it’s just no contest !

I think many folk forget that the Manx was a full on factory GP bike. Most major components (like crank cases, heads, all engine internals, wheel hubs, brake plates, even the 531 frame) had a designed life expectancy that meant they should be scrapped before a Vin even needed a de-coke...

desmo · Dec 11, 2019

we had a local agricultural mechanic ALEX PHILIPS
who tuned and rode his vincent to a class win in the 1950 Iom tt at 80mph average
it was going very well and he rode the bike home to Angus in scotland
on the journey home with wife on the pillion he had a crash near home damaging the bike

someone asked where his breaking point was at a particular bend ! his reply was when the marshall jumps out of the way

think the bike was gathered together from various places and sold at a recent bonhams auction house

worntorn · Dec 11, 2019

Here's how we travel. I'm the fellow at the rear, 6'1+and 230lbs + riding gear. My wife is leaning on the bike. She is fit but not a petite person. Both panniers are full at 45 lbs each. The big top box is full at around 60 pounds. The tool tray under the seat is also full at about 10 lbs.
Total weight when we are on board must be over half a ton. I would say right around 1100 lbs.
Now picture a Norton Manx somehow loaded this way trying to start off in traffic on an uphill grade.
One might rethink the sentence " A Manx would cream a Vincent.. "
The Vincent will do this whenever needed. It just pulls away smoothly with a wisp of throttle. That's when you are going through the towns, which is part of every big tour.
Out on the open road , loaded like this, it will haul up long Mountain grades at 75 mph in top Gear without effort. More often than not, the uphill grade is miles long and it's an opportunity to pass a long line of slower traffic. Drop it down a gear and it will pull those hills at 85mph or so, amazing for the weight being transported.
This particular bike has been used hard like that for all of its 72 year life. I'm the fifth owner. It's been ridden all over the world.

worntorn · Dec 11, 2019

Having fun on the same bike at the IOM 2007.

On 2500 mile tour of England and Scotland after the IOM.
First photo in the Dales, second is beside Loch Ness

Same bike in Australia in 1998. It ran 80,000 miles in 23 years there for two owners. The first owner crossed the continent with it 3 times on holiday and used it as his daily vehicle. It was his only transport.

Prior to that it was used for a decade or so in Scotland. Before that an English owner piled miles on it for years. Before that it lived in Malta.

I'm sure this bike is going to outlive me as well. I often think about what a great creation the two Phil's came up with. Riders have been getting pleasure from this one for seventy two years and it is still ready to go.

HRD · Dec 14, 2019

re the twin clutch,P.C.Vincent wrote in his 1975 book "The Vincent HRD Story" pages 121-122 ,"This clutch has unfortunately gained a very bad reputation during the thirty years that have elapsed since it first appeared,partly due to one or two minor errors that we made, which I will now describe ,......."
" The biggest error that we made in the original design of the clutch, which continued right through until production was finished in 1955,lay in making the toggle links a few thousandths of an inch too long.As a result the links reached their fully home driving position just before they were radial enough to exert maximum pressure......"
PCV then goes on to suggest that shortening the toggle links in steps of two to three thousandths of an inch .
Also I seem to remember hearing Phil Irving , while at the Vincent HRD International rally in Sydney, Australia in 1983 spoke about the same toggle link as being ,"dimensioned incorrectly by the drawing office" when questioned about the clutch.
Paul

HRD · Dec 14, 2019

swooshdave said:
I believe John’s Comet is at Barber. Anyone care to speculate on what clutch this is?

This is a single so clutch is not same as the twin's servo clutch .
Paul

acotrel · Dec 14, 2019

Between my brother and his friends there are 5 Vincent speedway outfits. My brother is always working on them. The other day he said ' if there is ever way to do something the wrong way when making a motorcycle, it has been done on a Vincent'. Every bolt is a special - it means you are always in the hands of the dealers. Phil Irving was an Australian, so we should all love Vincents. But he also designed Velocettes - another piece of crap. I actually knew him. I had to laugh, one of my mates shit-canned him at a race meeting, within hearing of his widow.