Octane rating for Nortons?

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The one positive thing I got from the cheap O'Reilly boost juice and whatever little bit of octane it added to the pump gas is that the motor actually did run a little cooler with some boost juice in the tank. No flakes at all after a 100 mile test ride today. Plugs are still a very light tan, and I can't see the little end of the connecting rods through big holes in the top of my pistons. I only hit 85 MPH today, but 70 MPH a couple of times in 3rd, so it was wound up enough to make it warm in the combustion chamber. Maybe it's tuned right.

There is a Triumph dealer not too far from where I reside, but that is not doing me any good. I called once, and confused them asking about British standard nuts. What? We don't carry that old stuff.
 
illf8ed said:
Speaking of shops in Seattle….Deweys was just north of Poke’s. All gone now.
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Marcia moved Dewey's down to Georgetown in the 90s, next to MSI. She was real sick with emphysema from chain smoking so long, and had an O2 bottle and nose clip she would drag around. She still smoked with that in.

I had Steve heliarc the exhaust thread repair inserts while at the old shop on 12th. I also bought a Hurricane from them at the old shop.
 
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The best I can get here in Sweden is 98 octane, this has max 5% ethanol in it. Shell have something called V-Power but I don´t think that has a higher octane level than 98 as well. There´s no petrol/gas here that is totally free of ethanol, I run my bikes and old cars on the 98, works fine.
 
Schwany said:
The one positive thing I got from the cheap O'Reilly boost juice and whatever little bit of octane it added to the pump gas is that the motor actually did run a little cooler with some boost juice in the tank. No flakes at all after a 100 mile test ride today. Plugs are still a very light tan, and I can't see the little end of the connecting rods through big holes in the top of my pistons. I only hit 85 MPH today, but 70 MPH a couple of times in 3rd, so it was wound up enough to make it warm in the combustion chamber. Maybe it's tuned right.

There is a Triumph dealer not too far from where I reside, but that is not doing me any good. I called once, and confused them asking about British standard nuts. What? We don't carry that old stuff.
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Slightly too rich is probably 'tuned right' for a road bike. The bit slower it goes is probably insignificant unless you are having a thrash with your mates.
 
acotrel said:
Slightly too rich is probably 'tuned right' for a road bike. The bit slower it goes is probably insignificant unless you are having a thrash with your mates.
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Road bike/Race bike makes no difference as far as how I would tune is concerned. Stuck in my ways. I might even know what I'm doing. It's possible. Richer would run a little cooler than my current tune does, but I would never tune too rich if I could avoid it myself. That reminds me I need to go pick up a pair of cooler running plugs.
 
I would not tune a road bike differently from a race bike, but I am prepared to raise the needles in the carbs when the weather gets cold. With methanol fuel, half a thou of an inch in needle jet internal diameter makes a significant difference - petrol is twice as critical. But for a road bike, you would never know the difference. Most guys would be able to run either of the two Amal needle jets which are specified for the Commando and probably never detect the difference in performance. With most road bikes, you do not ride them around in circles, changing the carb settings. How many guys try different taper needles in their Commando's carbs ?
 
My carbs are jetted for methanol. I use the slowest taper Mikuni needles - 6D . If I lower them one notch, I get the cough in the motor when I ride the bike. The jetting is so lean, I have to ride the bike like a two stroke - feed the throttle on. If I whacked the throttle open, the motor would just gasp and accelerate the bike slower - 'There is a fine line between pleasure and pain' ?
I never race using petrol as fuel, it is too difficult. You can get the motor going just as fast, but it is a lot of work.
 
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