Inlet upgrade?

Personally, if I were removing the stock TBs, I’d definitely go the FCR route as it would also remove a lot of other known 961 foibles.
This is my fantasy.
Love to see someone develop this into reality.
Ollie was supposed to be working on it, Dave Coote too.
I dream about it frequently.
 
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I also had fantasies about fitting FCRs, but now that I've got the EFI sorted out, it works so well that I've lost my motivation to change to carbs. But I do like the idea of trying to get some more power out of the engine, if I could ever get around to it :rolleyes:. In that case, larger throttle bodies might be worthwhile to go along with more displacement and a cam update. But that's pretty low on my priority list at the moment.

Ken
 
On the Triumphrat forum a member actually adapted 2 Keihin throttle bodies from a Street Triple and cut down the linkages to work on a Bonneville 903. He also went the Hi Compression piston, and cam route and the results were tremendous. The intake manifolds were port matched with the head, but no major porting work was done. I think the TBs were 44mm, or 46, can't remember.

I'm sure the Keihin TBs and injectors can be controlled by the SC Delta ECU, and TBs can be sourced off ebay.
Nice project for a bored 961 owner, no?
 
Sorry to pollute this thread but:

One reason I machined new manifolds to fit 54 mm (iirc) SP-1 TB's to one of my TL1000S's.
Later getting 61 mm SP-2 TB's.

DSC02120 (Small).JPG


DSC02147Small.JPG


Prior to that I had cut down and over bored stock TB's with custom titanium butterflies with an altered seated angle.

DSC0TB9.JPG


Anything would be possible with the Norton 961 if you were so inclined.
 
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There is somebody selling new 961 Jenvey bodies and injectors complete for £225 (or offers)

I bought one of these. I will post when it come in.
 
I bought one of these. I will post when it come in.
Here we go finally ! After having found air filters that fit and can flow enough air for a 961 , I have the beginnings of a plan :

Inlet upgrade?


Inlet upgrade?


After approximating the head angle in the frame , it is obvious that a straight shot is not possible . So , as others have shown a curved intake is necessary : More like this , Naturally , some trimming is in order .
Inlet upgrade?

There is also the Harley Davidson curved into the wind approach like Free Spirits of Italy does for the XR1200 or the Triumph Thruxton Intake :

Inlet upgrade?


Again some trimming is in order :

Inlet upgrade?


I think there really needs to be a Thread dedicated to the Norton 961 performance upgrades.

From the Free Spirits Italy Website :

Inlet upgrade?
 
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Here we go finally ! After having found air filters that fit and can flow enough air for a 961 , I have the beginnings of a plan :

From the Free Spirits Italy Website :

Inlet upgrade?
Tony,

Are you telling us you're buying a SpeedTwin?:p
 
Here we go finally ! After having found air filters that fit and can flow enough air for a 961 , I have the beginnings of a plan :

Inlet upgrade?


Inlet upgrade?


After approximating the head angle in the frame , it is obvious that a straight shot is not possible . So , as others have shown a curved intake is necessary : More like this , Naturally , some trimming is in order .
Inlet upgrade?

There is also the Harley Davidson curved into the wind approach like Free Spirits of Italy does for the XR1200 or the Triumph Thruxton Intake :

Inlet upgrade?


Again some trimming is in order :

Inlet upgrade?


I think there really needs to be a Thread dedicated to the Norton 961 performance upgrades.

From the Free Spirits Italy Website :

Inlet upgrade?
Positioning wrt getting wet needs to be considered, especially if ditching the airbox.
 
Tony,

Are you telling us you're buying a SpeedTwin?:p
I would never say you couldn't give me one ! BUT , I had a chance to buy one and you guys saw what I bought didn't you ? Not a Speed Twin . ;) :rolleyes:
 
Tony,

Good luck with the induction project.
Let us know what transpires.
 
Tony,

The XR1200 nice, but this is the one we want to see installed.

Inlet upgrade?
Hosted on Fotki
Hot Rod Norton 961 : PHASE 1 , not finished , more trimming and fitting needed.

Inlet upgrade?


Inlet upgrade?


Inlet upgrade?


So far so good. I was trying to form an intake runner with the black hose . I think this is going to work good ! Making it look nice will come later , once I know its worth the effort .
 
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Tony
Please don’t be offended by me asking this.
but what’s the reasoning?
looks?
performance?
both?
 
I did this three years ago when I was fixing the idle issues. Ran fine, although was just a temporary setup at the time with sensors dangling in thin air.



On the subject of increasing the throttle body size it's doubtful there are any gains to be made. If you increase the throttle body size you lose part throttle control as well as reducing the velocity of the air which leads to a loss of mid range torque where the engine spends most of its time. Also if any part of the inlet tract is smaller like the ports then it's a waste of time. But I'd be very interested to see the results of any experiments esp. with before and after dyno runs.

On a side note I got rid of that awful oil/air separator years ago, absolutely no issues now. My little pot only seems to collect water with a smudge of oil.

 
Hot Rod Norton 961 : PHASE 1 , not finished , more trimming and fitting needed.

Inlet upgrade?


Inlet upgrade?


Inlet upgrade?


So far so good. I was trying to form an intake runner with the black hose . I think this is going to work good ! Making it look nice will come later , once I know its worth the effort .
Looking good! Something to watch......now there's a clear path for water from the back wheel, above the hugger, in the wet the filters get soaked. Had to fit additional guard to stop this on one of mine.
 
Very interested to see how this performs Tony. The fact that you have long hoses between the injectors and filters is likely to effect things I suspect, and personally I’d be surprised if it was for the better. You have effectively increased the length of the inlet tract, doing this on a carbureted engine definitely effects things, sometimes for the better, sometimes not.
 
Looking good! Something to watch......now there's a clear path for water from the back wheel, above the hugger, in the wet the filters get soaked. Had to fit additional guard to stop this on one of mine.
I am working on a plate to cover this area , coming soon.
 
I did this three years ago when I was fixing the idle issues. Ran fine, although was just a temporary setup at the time with sensors dangling in thin air.



On the subject of increasing the throttle body size it's doubtful there are any gains to be made. If you increase the throttle body size you lose part throttle control as well as reducing the velocity of the air which leads to a loss of mid range torque where the engine spends most of its time. Also if any part of the inlet tract is smaller like the ports then it's a waste of time. But I'd be very interested to see the results of any experiments esp. with before and after dyno runs.

On a side note I got rid of that awful oil/air separator years ago, absolutely no issues now. My little pot only seems to collect water with a smudge of oil.


Hello Iwilson , Your work inspired me so to speak. I have ordered a oil breather like the one you fitted and will give it a try.
 
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