I haven't read thru this entire thread yet, but I did see mention of John McDougall's bike with its O2 sensors up close to the exhaust ports.
Those are narrow band sensors which rely on exhaust heat. They have no heating element of their own so must be up fairly close to the action.
When fabricating the pipes for my 1360 I included an O2 bung for a wide band sensor just after the 2 into 1 collector. John's info was that with all of the O2 related tuning he never found the need to use different jets on one cylinder vs the other.
So the single hidden bung should do the trick.
Now an admission.
Ive never gotten around to checking the AFR and I'm not sure that l will.
The jetting was as suggested by Terry Prince for that motor fitted with Dellorto 41 pumper carbs. It seems spot on, which is interesting because Terry also mentioned that at that time no one had assembled an engine at that spec.
I think he based the info on Vincent 1200s with the same Manx style combustion chambres which he or his customers had built and fitted with Dellortos.
Making the engine bigger actually meant reducing the mainjets a little from a 1200cc engine size, which I did.This makes sense if you wade through Bernoulli's work.
Somewhere in there he explains that the flow in a Venturi increases at the square of the flow thru the main body.
I thought that if anything the engine might still be a tad rich, however on an easy cruise it managed 60 mpg Imperial, just a shade better than my standard 998 Rapide.
That was a pleasant surprise. I had made an assumption that with the large displacement high performance carbeuretted engine, fuel mileage might not be great, maybe something similar to to Buick Wildcat numbers.
It's feels good to go Green!
Glen
Those are narrow band sensors which rely on exhaust heat. They have no heating element of their own so must be up fairly close to the action.
When fabricating the pipes for my 1360 I included an O2 bung for a wide band sensor just after the 2 into 1 collector. John's info was that with all of the O2 related tuning he never found the need to use different jets on one cylinder vs the other.
So the single hidden bung should do the trick.
Now an admission.
Ive never gotten around to checking the AFR and I'm not sure that l will.
The jetting was as suggested by Terry Prince for that motor fitted with Dellorto 41 pumper carbs. It seems spot on, which is interesting because Terry also mentioned that at that time no one had assembled an engine at that spec.
I think he based the info on Vincent 1200s with the same Manx style combustion chambres which he or his customers had built and fitted with Dellortos.
Making the engine bigger actually meant reducing the mainjets a little from a 1200cc engine size, which I did.This makes sense if you wade through Bernoulli's work.
Somewhere in there he explains that the flow in a Venturi increases at the square of the flow thru the main body.
I thought that if anything the engine might still be a tad rich, however on an easy cruise it managed 60 mpg Imperial, just a shade better than my standard 998 Rapide.
That was a pleasant surprise. I had made an assumption that with the large displacement high performance carbeuretted engine, fuel mileage might not be great, maybe something similar to to Buick Wildcat numbers.
It's feels good to go Green!
Glen
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