Manx Norton’s have more in common with Moto GP bikes than we might think…

My point is that with rider weight added to the equation, the numbers change a lot.
And to date, you always need a rider!

Almost all power to weight ratios are given as weight of riderless bike ÷power. I'm guessing that is how you calculated the 110 rwhp figure?

Glen
 
Fast Eddie said:
Correct. For both. So a fair comparison IMHO.
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The power to weight ratios change quite dramatically when you add in the rider.
The lighter bike's ratio moves toward the heavier bike by quite a chunk.
The chunkier the rider, the greater the reduction in advantage for the light bike.


So you have the right idea with the 920 Maney, get more bhp!
Weight reduction is wonderful, but that common number of 6 lbs= 1 bhp isn't reality with the rider added to an old 50-60 bhp bike. More like 12 or 14 lbs= 1bhp.





Glen
 
Yes I think your right there, but when there is such a large margin of difference to begin with, even adding my 95kg into the equation, the Manx still wins.

However, if we were talking a road going Manx with more weight and less power, they‘d probably be neck and neck.

On the road there’s no doubt (in my mind) the Commando would be, by far, the nicer bike to ride. In fact I could easily imagine a Manx would be quite horrid on the road.

But on the track, the light weight of the Manx must give huge dividends in terms of handling and braking even if you ignore the power to weight ratio!

When I first started racing, a chap called Doug Jones (RIP) was racing one of the first Molnar Manxes (stock bore and stroke too). He’d enter it in all sorts of classes just for fun. The lads in the Pre 72 unlimited class even complained about him “it’s not fair, it’s a GP bike” even though they were on Tritons, Nourish engines, Commandos, Tridents, Rob Norths, etc !

As a mate of mine who’s spent decades racing Commandos, but recently added a Manx to the stable said “it’s just a marvellous thing to ride. It makes me a better rider”!

As you can tell, I’m quite smitten !!
 
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When I was 14 years old my older Brother and I went out to Westwood.
This was 1968, the 750 Nortons were there along with the hot 2 stroke Yamaha and Suzukis of the day.
Pete Kellond on his 59 Manx held them all off for the win.
Every race.
Yeah, I would love to own and ride one too.

Glen
 
Well I had a very interesting event yesterday…

At Cadwell Park with my 920 Commando, which really doesn’t hang about.

I accidentally had the gearing just about perfect, hitting peak rpm in top at the end of the straight (on a good lap).

I rode behind a friend on his 4 valve Manx for a bit. On the straight, starting from right behind him, I could just about get my front wheel along side him, no chance of getting past him.

And that’s on my 920 with the gearing cock on for max speed down the straight.

I was amazed. Yes the Manx is perhaps 100lbs lighter and yes it’s fully faired, but still, I really wasn’t expecting it to be that quick.

Then it turns out his bike was running rich and not even revving out fully FFS !

And then… he let me have a go on it... oh my word… suddenly my Commando felt like a Transit van !!
 
Fast Eddie said:
Well I had a very interesting event yesterday…

At Cadwell Park with my 920 Commando, which really doesn’t hang about.

I accidentally had the gearing just about perfect, hitting peak rpm in top at the end of the straight (on a good lap).

I rode behind a friend on his 4 valve Manx for a bit. On the straight, starting from right behind him, I could just about get my front wheel along side him, no chance of getting past him.

And that’s on my 920 with the gearing cock on for max speed down the straight.

I was amazed. Yes the Manx is perhaps 100lbs lighter and yes it’s fully faired, but still, I really wasn’t expecting it to be that quick.

Then it turns out his bike was running rich and not even revving out fully FFS !

And then… he let me have a go on it... oh my word… suddenly my Commando felt like a Transit van !!
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Sounds like a go on that bike may have gotten expensive for you.
 
worntorn said:
I recently watched a tuned Black Shadow racing against Manx Nortons at Donnington.
The Black Shadow did not win.
The surprising thing was the Manx acceleration out of the corners.
You would think that a 1000 cc Vincent would at least have them there.
Nope.



Glen
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That looks like the Lansdowne series Glen.

Some very quick lads up front in that series.

But, they’re the less trick Manxes, no short strokes and certainly no 4 valvers.
 
In my garage is a 2019 Husqvarna 701 Vitpilen- a bike I became enamored with because of its vague resemblance to a proper Manx and it’s shared single cylinder engine.

Mine has had its exhaust changed and a power commander fitted- its a very strong running bike, and weighs in at about 345lbs all up. It is a terrific ride, and only makes me want a Manx more.
 
Elfix said:
In my garage is a 2019 Husqvarna 701 Vitpilen- a bike I became enamored with because of its vague resemblance to a proper Manx and it’s shared single cylinder engine.

Mine has had its exhaust changed and a power commander fitted- its a very strong running bike, and weighs in at about 345lbs all up. It is a terrific ride, and only makes me want a Manx more.
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I have long admired the Manx too but had never actually ridden one until earlier this year when I had a ride on a top spec 4 valve Molnar Manx, exquisitely built and prepared by Martin Page at Minnovation Racing.

It was like stepping into another universe vs my own bikes I’ve been riding on the track…
 
It’s a bucket list ride for me, to be sure. I’ve raced a Honda RS250, and ridden TZ250, 350, and 750’s on the track- but the Manx still has an inescapable lure.
 
Fast Eddie said:
Yes I think your right there, but when there is such a large margin of difference to begin with, even adding my 95kg into the equation, the Manx still wins.

However, if we were talking a road going Manx with more weight and less power, they‘d probably be neck and neck.

On the road there’s no doubt (in my mind) the Commando would be, by far, the nicer bike to ride. In fact I could easily imagine a Manx would be quite horrid on the road.

But on the track, the light weight of the Manx must give huge dividends in terms of handling and braking even if you ignore the power to weight ratio!

When I first started racing, a chap called Doug Jones (RIP) was racing one of the first Molnar Manxes (stock bore and stroke too). He’d enter it in all sorts of classes just for fun. The lads in the Pre 72 unlimited class even complained about him “it’s not fair, it’s a GP bike” even though they were on Tritons, Nourish engines, Commandos, Tridents, Rob Norths, etc !

As a mate of mine who’s spent decades racing Commandos, but recently added a Manx to the stable said “it’s just a marvellous thing to ride. It makes me a better rider”!

As you can tell, I’m quite smitten !!
Click to expand...
The bike trains the rider . Manx Norton's overseer as they accelerate
Can be ridden faster.
 
What I like about riding the Manx is that it is so forgiving of rider mistakes. Even when going a completely wrong line it sorts it out and exits the bend in the right spot.
Even more than on Dommies. Which has an overweight problem.
 
The Manx was the first bike I rode which oversteered except for my T110 when I carried a pillion passenger. In that case it was unsafe. But with a slow race bike it is important that you do not run wide in corners as you accelerate through them.
 
acotrel said:
The Manx was the first bike I rode which oversteered except for my T110 when I carried a pillion passenger. In that case it was unsafe. But with a slow race bike it is important that you do not run wide in corners as you accelerate through them.
Click to expand...
With a fast bike it is OK to join the procession out wide then blast down the straight.
 
There was once a video of Wayne Gardner riding a Manx. he cried and said he never knew what they were racing
 
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