- Joined
- Apr 13, 2021
- Messages
- 299
Hi all,
This is an interesting topic, apart from the practicality of the question, it naturally leads to the more complex issue of why we own and ride our bikes at all. Obviously almost every aspect of our bikes, particularly the carburettors are now obsolete and they do nothing that can’t fundamentally be done better by something newer. Yet here we are getting great enjoyment from our Nortons.
There are those amongst us who insist on absolute concourse originality, and good luck to them.
There are some, particularly those involved in various motor sports, who wildly modify their bikes and achieve stunning (if short lived) performance from our antiques.
And then there is the majority of us owners who wish to retain the appearance and heart and spirit of our bikes as they were sold and ridden half a century ago. And this is where I sit on the spectrum. I’m totally happy to make minor modifications that improve our bikes rather dubious reliability, safety and hopefully even lift their performance. The obvious mods that spring to mind are electronic ignition, master cylinder diameter, headlight bulbs and a some internal parts either better designed or manufactured than the bike was originally equipped with. So modified, for all intents and purposes our bikes largely represent what our bikes were like in their heyday.
So where do carburettors fit into all of this? They really seem to occupy a bit of a grey area, some would argue an unacceptable shift from originality, others a relatively minor upgrade. For me carbs are not only a vital major engine component but also strongly affect the visual appearance of the bike and it’s riding characteristics.
Few would disagree that the alternative carbs are superior to our Amals in almost all respects. The question is whether or not the gains in reliability and possibly performance are worth changing the appearance and character of the bike.
This is my opinion
Although primitive, rather poorly built and prone to wear, a well set up pair of Amals is capable of giving a very good performance. They will use more fuel and need a little fettling. I believe that modern Premiers largely get around much of these issues. I think Amals were way past their ‘use by date’ by the time our bikes went out of production. By 1975 the idea of flooding a carb (other than the one fitted to your Victor lawnmowe) was positively archaic but nevertheless that’s how they came.
No matter which way I think about it, fitting a single carb is a retrograde step. Dual carbs not only enhanced performance but we’re an iconic symbol that the bike was designed as a performance machine. Say the word ‘Triumph and the word Bonneville instantly springs to mind. Why, it’s twin carburettors proclaimed performance. As for balancing and tuning, I’m sure an E Type Jag would be easier to live with if we replaced the triple SUs with a single down-draft Stromberg but I’m think we would all agree that that would be missing the point
For me, I would definitely invest in a new pair of Premiums. On the plus side, if correctly tuned they should provide excellent starting (complete with the whiff of petrol and a fuel stain down the side of the bowl). Performance reasonably as good as any twin carb set up and better than a single and maintain the general feel of the bike and look correct.
Before committing to fit a Japanese carb I would ask whether the owner has done everything to ensure the original carbs are in the best possible condition and are correctly tuned. Otherwise they may well be living in a ‘fool’s paradise‘ of comparing badly tuned and worn out Amals with new and correctly tuned Mikunis believing the difference lies solely in the change of brand. Any of us who can afford a Commando as a toy can probably afford the purchase of new Amals if required, tuning and their replacement in thirty years or so, if still around to need it.
Philosophically our bikes eventually become our very own ‘Ship of Theseus’. What constitutes an original bike or eventually what constitutes a Norton at all. Like the ‘farmer’s 100 year old axe’ that has had the head and the handle changed several times, ultimately we could replace our frame with something superior then upgrade to a better engine to take advantage of our new found handling improvements and revel in our ‘modern’ superbike performance but is it a Norton?
Just a thought
regards
Alan
This is an interesting topic, apart from the practicality of the question, it naturally leads to the more complex issue of why we own and ride our bikes at all. Obviously almost every aspect of our bikes, particularly the carburettors are now obsolete and they do nothing that can’t fundamentally be done better by something newer. Yet here we are getting great enjoyment from our Nortons.
There are those amongst us who insist on absolute concourse originality, and good luck to them.
There are some, particularly those involved in various motor sports, who wildly modify their bikes and achieve stunning (if short lived) performance from our antiques.
And then there is the majority of us owners who wish to retain the appearance and heart and spirit of our bikes as they were sold and ridden half a century ago. And this is where I sit on the spectrum. I’m totally happy to make minor modifications that improve our bikes rather dubious reliability, safety and hopefully even lift their performance. The obvious mods that spring to mind are electronic ignition, master cylinder diameter, headlight bulbs and a some internal parts either better designed or manufactured than the bike was originally equipped with. So modified, for all intents and purposes our bikes largely represent what our bikes were like in their heyday.
So where do carburettors fit into all of this? They really seem to occupy a bit of a grey area, some would argue an unacceptable shift from originality, others a relatively minor upgrade. For me carbs are not only a vital major engine component but also strongly affect the visual appearance of the bike and it’s riding characteristics.
Few would disagree that the alternative carbs are superior to our Amals in almost all respects. The question is whether or not the gains in reliability and possibly performance are worth changing the appearance and character of the bike.
This is my opinion
Although primitive, rather poorly built and prone to wear, a well set up pair of Amals is capable of giving a very good performance. They will use more fuel and need a little fettling. I believe that modern Premiers largely get around much of these issues. I think Amals were way past their ‘use by date’ by the time our bikes went out of production. By 1975 the idea of flooding a carb (other than the one fitted to your Victor lawnmowe) was positively archaic but nevertheless that’s how they came.
No matter which way I think about it, fitting a single carb is a retrograde step. Dual carbs not only enhanced performance but we’re an iconic symbol that the bike was designed as a performance machine. Say the word ‘Triumph and the word Bonneville instantly springs to mind. Why, it’s twin carburettors proclaimed performance. As for balancing and tuning, I’m sure an E Type Jag would be easier to live with if we replaced the triple SUs with a single down-draft Stromberg but I’m think we would all agree that that would be missing the point
For me, I would definitely invest in a new pair of Premiums. On the plus side, if correctly tuned they should provide excellent starting (complete with the whiff of petrol and a fuel stain down the side of the bowl). Performance reasonably as good as any twin carb set up and better than a single and maintain the general feel of the bike and look correct.
Before committing to fit a Japanese carb I would ask whether the owner has done everything to ensure the original carbs are in the best possible condition and are correctly tuned. Otherwise they may well be living in a ‘fool’s paradise‘ of comparing badly tuned and worn out Amals with new and correctly tuned Mikunis believing the difference lies solely in the change of brand. Any of us who can afford a Commando as a toy can probably afford the purchase of new Amals if required, tuning and their replacement in thirty years or so, if still around to need it.
Philosophically our bikes eventually become our very own ‘Ship of Theseus’. What constitutes an original bike or eventually what constitutes a Norton at all. Like the ‘farmer’s 100 year old axe’ that has had the head and the handle changed several times, ultimately we could replace our frame with something superior then upgrade to a better engine to take advantage of our new found handling improvements and revel in our ‘modern’ superbike performance but is it a Norton?
Just a thought
regards
Alan
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