Monoshock John Player??
- Thread starter jseng1
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When you have monoshock you only have one damper, with dual shocks you have two, so the single unit has to be more expensive to remain effective.
There was a change in lean angle when we got decent tyres in the late1960s. Previously Manx Nortons stayed more upright and were difficult to lean because of their geometry. A lot of guys changed the steering geometry and fitted 18 inch wheels to get good rubber. But a Manx is quicker with 19 inch wheels and good rubber, because it stays more upright and the rider can apply more power. Monoshock changes the equation because of the increased travel. To me the angle of lean on modern race bikes seems too extreme. In races they are all at the same lean angle and experience the same limitations. However a decrease in the lean angle might be more dangerous. The whole thing becomes a power game, not one you can win by changing the handling.
There was a change in lean angle when we got decent tyres in the late1960s. Previously Manx Nortons stayed more upright and were difficult to lean because of their geometry. A lot of guys changed the steering geometry and fitted 18 inch wheels to get good rubber. But a Manx is quicker with 19 inch wheels and good rubber, because it stays more upright and the rider can apply more power. Monoshock changes the equation because of the increased travel. To me the angle of lean on modern race bikes seems too extreme. In races they are all at the same lean angle and experience the same limitations. However a decrease in the lean angle might be more dangerous. The whole thing becomes a power game, not one you can win by changing the handling.
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My Seeley 850 is lighter than the Triton 500 I had before it. There is only so much you can do and still have decent power output. About the Cosworth - Car people cannot race motorcycles, but many motorcyclists have succeeded very well in car racing. I think Edward Turner was a car guy. His designs reflect that mentality. Also the guy who decided Commandos needed isolastics to compete with CB750s ? The crank balance factor is absurd. The balance factor of the Atlas 750 was almost 80 %. The isolastics don't stop you from pounding the crankcases with an out of balance crank..
Deckard
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Was that Yvon Duhamel in the background of the starting grid? Sure looks like him and he usually was #17
Yes, I'm quite sure that is YD, I know him quite well and have see many early pictures of him.
And yet,......you race a 850 Commando. ......
What's this statement, are you telling us you have never raced against a Manx Norton with a good rider on board who could ride like Geoff Duke?
Monocoque ?
corrected
By this context you are going to look as if you are sand bagging, when in the middle of a corner on a racetrack, a better designed bike overtakes you on the outside going some 10 miles an hour faster. . . . .
SteveA
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Not in the UK where replicas of one offs and specials are not allowed, only the original items...and pre '73 cut off dates for 'classics'
In France maybe, Belgium probably not because...pre '73
Or run as a post classic and lose the advantage you thought you had just bought!
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SteveA
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It's 'day' being the mid to late '80s, not the early '70s JPN period...the only thing like the 'P86' is the engine unit, and then, perhaps only the castings!
SteveA
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If we must go through the Cosworth again....no it didn't work....blame Cosworth? The car guys didn't know what they were doing!
Maybe not, but it is a matter or record that to some extent they did what the bike guys asked for, they designed an engine that could be used in a road bike! And someone put it in a race bike! Lots of stuff that the racer not only didn't need, but that made it a poor race solution. And they didn't add things it did need that would have made it a better racer, like a slipper clutch!
As for the monoshock? I have a BSA Fury/ Triumph Bandit framed race bike that was converted to monoshock. It handled really well, when it wasn't breaking the shock!!
It did that once too often (3 times) exiting a fast corner with me on it! And in France I can run it in a dedicated class if it has twin shocks, so I am in the progress of converting it back, at this stage I am not really expecting it to start handling like shit! But...eventually...we will see.
Maybe not, but it is a matter or record that to some extent they did what the bike guys asked for, they designed an engine that could be used in a road bike! And someone put it in a race bike! Lots of stuff that the racer not only didn't need, but that made it a poor race solution. And they didn't add things it did need that would have made it a better racer, like a slipper clutch!
As for the monoshock? I have a BSA Fury/ Triumph Bandit framed race bike that was converted to monoshock. It handled really well, when it wasn't breaking the shock!!
It did that once too often (3 times) exiting a fast corner with me on it! And in France I can run it in a dedicated class if it has twin shocks, so I am in the progress of converting it back, at this stage I am not really expecting it to start handling like shit! But...eventually...we will see.
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lcrken
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This is Dave on the bike at Daytona in 1974.
Pulled the picture off the internet from the sideburn magazine blogspot dated 2011. This is the heading for the photo:
"Dave Aldana at Daytona in '74 on a stainless-steel monocoque Norton (built in '73). One of my all-time fave bikes. BP"
That's all the info there was on the site about the picture.
This picture is also on Jamie Waters' site. Jamie is the current owner of the bike Dave was riding.
Ken
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I know you know, but for others that may not - monoshock is not same as monocoque.
Former is suspension, latter is chassis.
Dave was on a monocoque, not a monoshock bike in the pic, per quote and JW site.
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I found some more pics, none of the 74.
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Hard to tell which spaceframe this first pic is for?
It doesnt look like the geometry in this one?
It doesnt look like the geometry in this one?
cliffa
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As far as I can remember the NVT P86 "Challenge" never had a monoshock, but a conventional swinging arm pivoting off the rear of the engine which was a stressed member of the frame. It had dual vertical shocks mounted quite far forward and a strange outboard rear disc. By the time it eventually saw the light of day NVT were on their knees and there were appeals in MCN Or Motorcycle Weekly to the public to sponsor the team ( The Challenge fund I think) So I very much doubt it they had enough funds to create another frame.
Only later when it was used in the "Quantel" did it gain the monoshock and as can be seen in the pictures gortnipper posted there were at least two iterations.
I wonder whatever happened to the bike in the original post?
I had a brief email exchange with Peter Williams some years ago, and he said the Cosworth lump was incredibly heavy as Cosworth were car guys with no bike experience, so everything was massively overscale for a bike. Apparently interaction between NVT and Cosworth engineering teams was banned.
Only later when it was used in the "Quantel" did it gain the monoshock and as can be seen in the pictures gortnipper posted there were at least two iterations.
I wonder whatever happened to the bike in the original post?
I had a brief email exchange with Peter Williams some years ago, and he said the Cosworth lump was incredibly heavy as Cosworth were car guys with no bike experience, so everything was massively overscale for a bike. Apparently interaction between NVT and Cosworth engineering teams was banned.
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