Monoshock John Player??

Time Warp

.......back to the 70's.
VIP MEMBER
Joined
Dec 3, 2012
Messages
2,914
It might be dangerous to ride a prototype in a race without having it properly sorted.
Exactly, they should have got Burt Munro to have a look at it, with a bit of filing, hammer tapped water kettle pistons it might have been a 180 mph weapon.
#
The Cosworth engine might have been better if it was more motorcycle biased (not the end of a car engine) and had more magnesium.
Do not forget the benefits of later mono shock rising rate linkages.

The racing Norton's could have preceded the light weight cantilever TT2's.
 
Last edited:
Joined
Jun 30, 2012
Messages
10,625
Country flag
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.
 
Joined
Jun 30, 2012
Messages
10,625
Country flag
Exactly, they should have got Burt Munro to have a look at it, with a bit of filing, hammer tapped water kettle pistons it might have been a 180 mph weapon.
#
The Cosworth engine might have been better if it was more motorcycle biased (not the end of a car engine) and had more magnesium.
Do not forget the benefits of later mono shock rising rate linkages.

The racing Norton's could have preceded the light weight cantilever TT2's.
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..
 

Carl H

VIP MEMBER
Joined
Dec 13, 2017
Messages
130
Country flag
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.
 

Carl H

VIP MEMBER
Joined
Dec 13, 2017
Messages
130
Country flag
I just spoke with David Aldana #13, he said he rode the mono shock in Daytona ( If I got it right) and was wondering if there were any photos of him on it.
 
Joined
Apr 20, 2011
Messages
5,651
Country flag
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..
And yet,......you race a 850 Commando. ......
 
Joined
Apr 20, 2011
Messages
5,651
Country flag
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.
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?
 
Joined
Apr 20, 2011
Messages
5,651
Country flag
Re; 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.
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

VIP MEMBER
Joined
Dec 20, 2011
Messages
2,179
Country flag
If there were pics without the fairing and it was legal for classic racing it could be duplicated and would give the Norton an edge.
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!
 
Last edited:

SteveA

VIP MEMBER
Joined
Dec 20, 2011
Messages
2,179
Country flag
Dig the front brake anti-dive mechanism.

Trick stuff, for it's day...
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

VIP MEMBER
Joined
Dec 20, 2011
Messages
2,179
Country flag
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.
 
Last edited:

lcrken

VIP MEMBER
Joined
Mar 15, 2009
Messages
4,315
Country flag
I just spoke with David Aldana #13, he said he rode the mono shock in Daytona ( If I got it right) and was wondering if there were any photos of him on it.

This is Dave on the bike at Daytona in 1974.

Dave Aldano on the Monocoque.jpg


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
 
Last edited:

gortnipper

VIP MEMBER
Joined
Nov 11, 2013
Messages
4,077
Country flag
This is Dave on the bike at Daytona in 1974.

View attachment 79604

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
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.
 

gortnipper

VIP MEMBER
Joined
Nov 11, 2013
Messages
4,077
Country flag
Hard to tell which spaceframe this first pic is for?

peter_15.jpg


It doesnt look like the geometry in this one?

peter_17.jpg
 
Top