The changes I made on the sunburst

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Yves
Bring it up to 920cc again.
That should make you happy.
The changes I made on the sunburst
Hi Jim,
Is this a Maney?
Second hand or new?
81 bore?
Yves
 
There looks to be no springs so perhaps it is still threaded but more compact to the head and tightened at the front face.

If you right click on pictures, Search Google for image will find the source if it is online elsewhere.

What I think you will find is something similar to the solution that Norton used particularly for the space frame. They machined the head away around the port. Then they made stubs that were held on with 3 smallish allen screws. I had a ex-works short stroke head like that between late '75 and late '80, with a suitable exhaust. Norton also machined the side fins to clear the space frame on assembly.

Looking at the full set of pictures seems to confirm that. But this is a long stroke 750. However, Norton also used long stroke engines in the monocoque and space frame.
 
Hi Steve A
All I meant by the upright engines was that from my perspective they just look more 'right'. Just my view and highly subjective.
Thanks for the information about Rickman, I wondered why you don't see many Commando-engined ones. The pic I included therefore looks to be a customer bike with the engine inclined forward but not quite as inclined as a standard Commando.
This is the link that I grabbed the pick from https://www.classicsportbikesforsale.com/1968-rickman-metisse-roadracer-for-sale/
Not sure it helps with the exhaust ports.
Pics of some Triumphs with vertical engines here: https://www.classic-british-motorcycles.com/rickman-motorcycles.html
All imho
Andy
This photo shows the original Rickman Atlas style installation on my bike, which was built originally using a chassis from the last batch Rickman made for Norton engines. Don't forget the rear stand is quite tall here, imagine the top rails being horizontal.

The plates used were made to a pattern of one of my original '75 plates, entered into CAD and cut on a water jet machine at Aermacchi in Italy! (They were fun days!)

The '68 bike may not have originally been a Norton designated frame because it has the straight side tubes, used in '66 for the original 7R/G50s built for Tom Kirby. The 'kink' was introduced quite early for twins to accommodate twin carbs better. But that isn't conclusive. Also note this bike is missing a number of original Rickman items, and the Norton element is modified.
 

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Its a Maney cylinder. Sorry but its a photo of your old 920 cylinders before your crash with the woman who pulled out in front of you.
I have the 77mm bore Maney cylinders Yves used before the 920! I guess I better use them soon!
 
I
Right you are, use the Atlas cover!
It is a Commando cover with the original script welded up .
Reproducing the points cavity on an Atlas cover would be far more difficult.
(And then ift still needs to be engraved..)
 
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I

It is a Commando cover with the original script welded up .
Reproducing the points cavity on an Atlas cover would be far more difficult.
(And then ift still needs to be engraved..)
Shows how much I know about pre-Commandos, I thought the last ones had the Norton script...

That's some mighty fine welding, and engraving!
 
Its a Maney cylinder. Sorry but its a photo of your old 920 cylinders before your crash with the woman who pulled out in front of you.
I will not go to 920 anymore, at least not with a 81mm bore, maibe with a longer stroke.
It take to mutch work to avoid leaks on the head.
I agree that my 920 was crayzy fast, also with the big valves work made by Klaus Morning and the flow bench work from Werner, also with the solutions from Ludwig
The Sunburst is my first 750, so I dont know if I can put 850 sleeves in it and if I can still use my fullauto head on it??
To day I rode the Seeley from home to my workshop, not via my usual road, closed for works, but via downtown the city of Vivoorde, I tell you: a Seeley is not made for this and me to.
I am happy with the power made by Kenny Cumings, but it can be more for me.
Keep you posted
Yves
 
I hope the leak problem is history (even for 81mm bore) once the new STS cylinder barrels become available.



-Knut
 
... I dont know if I can put 850 sleeves in it and if I can still use my fullauto head on it??
...
Yves
You can adapt a 750 head to 850 cylinders by moving the 4 bolt holes in the 750 head outward but you can't machine 750 Maney cylinders out to 850 because those 4 bolt holes in the cylinders are too close to the bores and can't be moved.
 
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Yves, like Jim says, modifying the head is easy, not so the Maney barrels.

Andy Molnar (the Manx guy) is making Nickasil lined alloy barrels for 750 and 850 Commandos... I think the sunburst NEEDS these Yves...

The changes I made on the sunburst
 
Jus’ thinking out loud here...

With the ‘Big Spender’ not being a full cradle frame, I wonder if it stresses the head gasket joint more? Either through the engine acting as a stressed member and having various twisting forces applied, or through a lot of weight being ‘hung’ from the head joint, and then having vibration applied to it?
 
Jus’ thinking out loud here...

With the ‘Big Spender’ not being a full cradle frame, I wonder if it stresses the head gasket joint more? Either through the engine acting as a stressed member and having various twisting forces applied, or through a lot of weight being ‘hung’ from the head joint, and then having vibration applied to it?

Never had a problem in 30 years racing a very quick Mk3, but my head steady isn't rigid, I have 2 metalastic bushes in it as recommended by all who know
 
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