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Two wheels & four: 'the great divide'


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#51 subh

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Posted 11 January 2005 - 11:02

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#52 Jon Petersen

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Posted 12 January 2005 - 22:19

Hi!

Isn´t it true that the traditional explanation of the divide between motorcycle racers and car racers is very much a social/economical divide?

Bikes were (are) cheaper than cars, so if you were (relatively) poor and wanted to go motor racing, you would choose a bike. Being better off, you´d probably choose a car.

It seems to me, that the names of the Brooklands racers Bill Boddy writes about in Motor Sport all have a certain posh accent to them - that certainly wasn´t the case in the reports I read in Classic Racer (another Haymarket magazine?) in the eighties.

Does this still hold true to a certain degree?

Jon

Car racing fanatic - Yamaha XS 650 rider.

#53 Jon Petersen

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Posted 18 January 2005 - 18:03

OOOOPS!

It seems I - very unintentionally - killed off an otherwise very interesting thread.

It may seem like a bad excuse, but maybe I expressed myself clumsily - Danish is my first language - or did I write something that I shouldn´t? :blush:

Or do I overestimate my own importance and is it just because there has popped so many other great `bike threads up ? :up:

But - I really have been wondering about "The Great Divide", as I have felt it for many years, also among my fellow motorcycle riding friends.

I never quite understood it - I mean, of course it is different sports, but why eliminate one joy, because you have another ??

In the best intentions

Jon

#54 ADC_28

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Posted 18 January 2005 - 19:23

As an aside for a second, this talk of the TT and so forth has fired a previously dormant neuron...

Didn't John Watson demo a sportscar in the Isle of Man one year and use plenty of right foot to the alarm of onlookers? Or is my memory playing tricks? Does anyone have any photographs of the event?

Ta.

#55 T54

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Posted 18 January 2005 - 20:29

Isn´t it true that the traditional explanation of the divide between motorcycle racers and car racers is very much a social/economical divide?



If it used to be true, the gap has shrunk considerably. Check the price of a "works-assisted" MotoGP racing bike today and you will be in complete state of shock. It costs almost TWICE as much as a brand new IRL car... or 4 times the price of a Porsche GT2...
Even a "production" bike can run you a cool $150K according to the most recent Yamaha catalogue.
Now a set of Dainese leathers will cost you at least twice as much as the suit worn by the Shoe hisself, and let's not even mention the boots and gloves compared to auto-racing implements.

And the crew is being paid the same, regardless if they work on two or four-wheel machinery.

The "social" issue is a whole different subject altogether, and no doubt there that most motorcycle racers of distinction had much more modest social origins than most successful car racers. One needs money to get started either way but one can prove his talent on two wheels for a LOT less in beginners formulas.
Regards,

T54
"Raced for 45 years both bikes and cars and still broke."

#56 Bonde

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Posted 18 January 2005 - 22:37

I know others have expressed the same sentiment, but I agree that for sheer racing spectacle bikes are absolutely brilliant - as are karts. What I miss in both, however, is instantly visible differences between different makes and ages of bikes (and karts). Bikes (and karts) are very inconspicuoius - the rider covers at lot of it, and to me, like modern single seaters, not least F1, they all look very, very similar - and have done so virtually always. Visibly, to my non-expert eye anyway, bikes (and karts) have changed too little over the years - like F1 since the squished track/grooved tire silliness came around. Aesthetically, F1 cars have, IMHO, not evolved at all since 1998.

A thing that puts me off bikes, more than any other, is the number of spills; I just don't happen to enjoy watching human anatomy making initimate contact with tarmac. Also, 8 out of the 10 guys I know who ride/rode motorbikes (on the road and two of them race, too) have been hospitalized at one time or another due to bike accident injuries. Motor racing on 4 wheels is crazy enough, on 2 wheels it is total madness - as is selling overpowered 2-wheeled monsters to young kids with surfeits of testoteron; boys are bound to get maimed and killed on big bikes, and they do, big time.

Being mostly a chassis-fan myself, there is not too much of it on bikes (or karts, if they are done properly!), but I always found, and still do find, motorcycle engines, racing variety or otherwise, very varied and technically extremely interesting (singles, multis in all kinds of configurations, two stroke, four stroke, air cooled, liquid cooled) - and also the aesthetically most interesting portion of the bike.

And, of course, being in love with the early 500cc F3 cars we all owe so much, even single cylinder motor cycle engines and chain drive can warm my old f@rt heart...

#57 David Birchall

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Posted 19 January 2005 - 19:25

T54: your design makes a huge amount of sense. I recently returned to motorcycling, after a 40 year hiatus, and bought a Honda VFR Interceptor. 0-60 mph in about 3 seconds and 160 mph terminal speed! But... The large fuel tank is very high up and seriously affects low speed handling, the engine is so complex that it runs on 2 valves per cylinder until 7000 rph and then goes to 4! The fuel injected engine is SO resonsive that driving smoothly takes even experienced riders a considerable time to master. Lovely bike though :smoking:

Dan Gurney of course came up with a design that lowered the c of g but it seems moribund (?).

I haven't seen anything from our Kiwi friends about John Britten's marvelous designs. He tried wings on a bike! And succeeded in beating the works teams with brains and imagination rather than financial resourses.

The difference between bikers and car fans seems to be socio/economic and YOUTH. I made the (apparent) mistake of joining a bike chat group recently. It ended in tears with me withdrawing in the face of a fusilade of hostile posts from two young guys with nothing better to do than hurl insults. My crime? I had questioned the weight of the motorcylce the site was devoted to.

In 1980 when myself and two friends were organizing the first Historic Weekend at Westwood event we decided to make bikes an equal part of the programme so we invited the fledgling vintage motorcylce group to join us. They were thrilled but insisted that since they had half the number of wheels they should pay half the entry fee!
David B

#58 Macca

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Posted 20 January 2005 - 10:34

by David Birchall:

I haven't seen anything from our Kiwi friends about John Britten's marvelous designs. He tried wings on a bike! And succeeded in beating the works teams with brains and imagination rather than financial resources



The late great Rodger Freeth, in his biking days, fitted aerofoils front and rear to his Yamaha TZ750 in 1978 IIRC; and used it as his university engineering thesis! (I've got some pics somewhere)

Paul M

#59 philippe7

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Posted 21 January 2005 - 07:41

And even earlier, the MV Agusta factory had tried front wings on the fairing of Phil Read's 500 during practice for the 1974 Belgium Grand Prix at Spa.

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#60 T54

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Posted 21 January 2005 - 16:09

I have news for them: they did not need to bother. The changes in pitch and roll would force the angle of incidence of any wing to the extreme for any efficiency, causing excessive drag. One may get much better results with refining the actual shape of the vehicle and the driver's equipment, as we proved we the 250cc Morbidelli that won the 1978 Belgian GP by over a minute over the works Yamaha and Harley-Davidson. Low drag with moderate down force valid at any practical angle is best. Today, they have almost got to the same stage and the wind tunnels are a lot more sophisticated than what we had then...

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T54 :)

#61 David Birchall

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Posted 21 January 2005 - 17:15

The shape of my '02 Honda Interceptor seems very sophisticated and obviously creates downforce. People say is is perfectly stable at 150+ mph. I will take their word for it!
I had fogotten about MV's use of wings earlier....
David B

#62 T54

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Posted 21 January 2005 - 17:27

Read had a single test session with them. He came back slightly ruffled and said that it scared the heck out of him. The wings were promptly unbolted.
They reminded me of the diedral wings fitted by Maurice Philippe (after a drunken binge I guess) on the Vel's Parnelli Indy cars in 1972... after a quick test that frightened Al Unser, they were promptly removed from the cars and replaced by a conventional device parralel to Earth... :cool:
Maurice liked a good pint, and that day it showed.


T54

#63 Don Ludewig

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Posted 22 January 2005 - 08:33

Quote: Dane Rowe NEVER leaned out of the chair

Not completely true. She may never have leaned out of any of Rudi's CATs, but if you were in England in the late '60s you could have seen her passengering (and leaning out of) several different conventional "front exit" outfits before teaming up with Rudi.

#64 T54

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Posted 22 January 2005 - 16:21

Not completely true. She may never have leaned out of any of Rudi's CATs, but if you were in England in the late '60s you could have seen her passengering (and leaning out of) several different conventional "front exit" outfits before teaming up with Rudi.



Don, with all due respect, we were strictly discussing the Rudi Kurt outfit... I am very aware of the previous rides of Dana. I am also aware that she was seriously leaning from her high-chair to avoid swallowing British baby slop when only 2 years old. Who could blame her?
Regards,

T54 :)

#65 Macca

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Posted 16 March 2005 - 14:25

Not necessarily intending to drag this back up; but I found my picture archive and thought to post pictures of some of the technical stuff about sidecar outfits:

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steering of 1977-78 Seymaz

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basic layout of the 1978 BEO-Imagine (driver kneels, passenger sits)

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1979 LCR for B2B WC (driver Rolf Biland sits)

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1979 LCR with fairing on


Paul M

#66 Macca

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Posted 16 March 2005 - 15:06

I'm not sure if these pictures are visible.............

Paul M

#67 fines

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Posted 16 March 2005 - 18:16

Rest assured, they are!

Very interesting, thanks!

#68 Bonde

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Posted 16 March 2005 - 21:20

They most certainly are, and very interesting, to boot! :up:

Thanks, Macca!

Sidecar chassis seem to inspire a lot of originality - highly asymmetric three-wheel cars in many ways, really. It just looks like such a dangerous proposition to me - like a car without seatbelts or roll hoop! From what I've seen, there chassis structures are still manufactured from riveted sheet aluminium alloy - but I suppose crashworthyness isn't much of an issue if you're thrown clear in any major accident?

BTW, I really like those old pen-and-ink technical drawings like the ones you posted - don't know why, but for some reason I prefer them to all the colourful, fancy 3D soild models and computer renderings we are presented with today - where half of the time it looks like the guy who steered the mouse and keyboard didn't really understand his subject, but sure made it look convincing anyway! Oh, well - I'm just an old f@rt that likes the human touch in an illustration, I guess...

Re the opening post: I suppose one could say that where cars and bikes are 'cross-bred', trikes and sidecar outfits have dominant bike genes, and such as the typical 500cc F3 car and other bike-engined cars have dominant car genes. And there were, of course, a few car-engined bikes - the name Münch comes to mind - and trikes, too.

(oie- fines beat me to it!)

#69 David Beard

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Posted 16 March 2005 - 21:32

Something I used to ponder about these wonderful wishboned outfits...

A three wheeler with a left hand chair corners better on a right hander, yes? So whereas a racing car has suspension geometry that pays more attention to camber change with roll on the outside wheels, would a sidecar outfit have suspension geometry on the " bike " wheels such that the camber change is controlled more on the inside?

(Hope that made sense : )

#70 Bonde

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Posted 16 March 2005 - 21:57

David,

If I understood you correctly, you do make sense!

This is pure speculation on my part - I've never studied the dynamics of sidecar outfits - but they appear to me to run on what looks like relatively wide, low profile car tyres, so camber change (and roll) is probably kept intentionally low by stiff springs and a low center of gravity (the wishbones I've seen are almost parrallel and equal length, which doesn't permit much roll), but then again with the pasenger moving about as he does, they have a solution to minimize the roll-induced camber/weight transfer problem that isn't available to us car folks!

#71 fines

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Posted 19 March 2005 - 12:57

Perhaps Éric Vuagnat and Louis Christen should join this thread, having successfully built racing cars and sidecars...

#72 Macca

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Posted 13 April 2005 - 12:45

While looking for something else in my albums, I found these two.........the first shows a professionally-built 500cc GP long-wheelbase hub-centre-steering 'worm' outfit from about 1990, the second an amateur attempt to copy the long-wheelbase aspect in a cheap way for club racing (I hope it was never finished!).

Paul M

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#73 Toypop

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Posted 13 August 2006 - 19:43

More info on Owen Greenwood. Any idea what became of this machine?

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#74 David Beard

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Posted 13 August 2006 - 20:04

Originally posted by Toypop
More info on Owen Greenwood. Any idea what became of this machine?


Toypop...thanks for those scans. I have no idea what happened to it, but I'm fascinated that your first post on TNF homes in on Owen Greenwood and his infamous Mini Special. Do you have a special interest?

#75 Toypop

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Posted 13 August 2006 - 20:25

Posting on behalf of my father (57) who doesn't know how to use a PC, his words:

"I saw it racing at Castle Combe in 66 or 67, it was a brilliant machine. It used to start from the back of the grid and then by the end of the first lap would be up in 3rd place and then win the race easily against top racers like Chris Vincent.

I used to see the rider working hard at the controls, it was stable but you could see him controlling the drifts.

I remember that he started off with drum brakes all round in the early days and then moved onto disks at the front. Later on he fitted a limited slip diff and special valve springs to obtain higher revs.

The body work had a polished aluminium look to it.

It was the start of a new generation of sidecar chassis which led to the worms and other riders experimenting with car engines.

I just want to know if it still exists today and if it is in a museum or something. I know Owen died a few years ago and also wonder if the passenger Terry is still alive."

He is very much into classic bikes, historic motorcycle racing and has many memories to tell. He is also very much interested in the engineering side of things. Alas his IT skills do not match his enthusiasm for the subject...

#76 David Beard

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Posted 14 August 2006 - 12:00

Originally posted by Toypop
Posting on behalf of my father (57) who doesn't know how to use a PC


He's the same age as me, and I'm a youngster here :eek:

Toypop, you need to sort him out ;)

#77 renzo

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Posted 14 August 2006 - 15:52

the greenwood mini was actually up for sale not so long ago,being sold by his son if i remember?
anyway it was in classic racer mag for sale dept.
wonder if it got sold?

#78 subh

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Posted 14 August 2006 - 20:32

Originally posted by philippe7
Rudi Kurth

......and by the way....he was also the first GP sidecar rider to put a lady ( and a nice looking british one ....) in the passenger basket . Dane Rowe, the lady was called


Here she is:

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#79 steve-e

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Posted 13 December 2006 - 12:51

The greenwood mini came up on ebay not all that long ago. Fetched an unremarkable sum as I recall for what seemed such a historic piece. All the guys on our forum that looked at it reckoned it was the real deal too, not a replica/copy/ripoff.


While looking for something else in my albums, I found these two.........the first shows a professionally-built 500cc GP long-wheelbase hub-centre-steering 'worm' outfit from about 1990, the second an amateur attempt to copy the long-wheelbase aspect in a cheap way for club racing (I hope it was never finished!).



That looks to me like a fairly common long tubular chassis and yes it does look finished to me. What do you think is missing?
They are still very popular to this day at club level (and would be at National level if we had one at this moment), very controllable to drive and more stable generally over bumps than the hub centre steered outfits.
In fact, I think the last time Sean and Mark Hegarty won the British F1 series it was on a very similar machine, not more than about 5 years ago (a bit vague, my apologies).

A three wheeler with a left hand chair corners better on a right hander, yes? So whereas a racing car has suspension geometry that pays more attention to camber change with roll on the outside wheels, would a sidecar outfit have suspension geometry on the " bike " wheels such that the camber change is controlled more on the inside?



The difference between left and right corner speeds is quite minimal on the latest outfits. We have no suspension on the 3rd wheel at all, them's the rules, but the rear geometry has always (when correctly fitted) adjusted for camber roll (although we have generally less than an inch of travel so it's hardly noticeable). The front suspension as shown in that early photo (the front end design is different now) used to move purely up and down, which moved the centre point of the tyre contact relative to the centre through the 'kingpins' with varying chassis height. This led to bump steer and the nickname 'worms'. This has largely been corrected in the latest versions.

hope this helps a touch

steve english

http://www.stevesplace.org

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#80 steve-e

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Posted 13 December 2006 - 13:00

For more info on Rudi Kurth and other outfits of the era, try on my forum here.
I've just altered the permissions so anyone can read that section of the forum.
I think you'll find some bits of interest :)

http://www.steveengl...wforum.php?f=26