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Discussion Starter #1
Well the Norton finally came in. In my eyes she's a beauty, rough but still a beauty. Right now I think she needs a good detailing as I don't have the time to give it the attention it needs, this will give me time to source parts. Here's the short term plan.
1. Stripe the lights and wiring to them
2. Repair the front number plate, windscreen and seat
3. The tank. WTF was someone thinking with hot oil and fuel in the same tank. The tank has a number of bad paint jobs and the inside has a bunch of resin in it, I think the original paint is under there but first I'm going to try to dissolve the resin with low heat and ethanol trying to save the outside of the tank.
4. Start soaking everything with penetrating oil.
IMG_3687.JPG IMG_3688.JPG IMG_3689.JPG IMG_3690.JPG
 

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in would scope the bores and valves amomngst other things before fire or even crank revolution with a wrong fitting spanner
unless i knew recent history
 

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3. The tank. WTF was someone thinking with hot oil and fuel in the same tank. The tank has a number of bad paint jobs and the inside has a bunch of resin in it, I think the original paint is under there but first I'm going to try to dissolve the resin with low heat and ethanol trying to save the outside of the tank.
So that's a thing you see on a lot of older race bikes - 1950's (early 60's) and earlier. I think this is before oil coolers and one way to cool the oil in a racing environment was to put it next to fuel. being vaporous, fuel is actually a pretty good coolant despite being flammable, and it really doesn't get hot enough to instantly vaporize and the line to the carb is out in open air so it isn't a hot as you think. Plus you kinda want warm fuel because it atomizes easier and vaporizes faster which increases it's thermal efficiency, so long as it isn't boiling.
 

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that would be excellent with usable rear suspension and something to .well .straight pipes are just completely obnoxious
why do you want to ride around pissing off the public \?
 

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Discussion Starter #7 (Edited)
that would be excellent with usable rear suspension and something to .well .straight pipes are just completely obnoxious
why do you want to ride around pissing off the public \?
Because that bike was built around 1981 by Denver Choppers. It was in Easy Rider magazine, it is completely original as Mondo built it, It doesn't get out that often but then again if people don't like the sound fuck em! I like it!!! Yes it's loud, the motor is "built" and for a Panhead it moves. It's a fun bike to ride. Oh wait let me give you the "loud pipes save lives" BS line
And one more, I generally I don't like most people, so fuck em all, I put up with how they want to live their shitty lives, but they seem to want to fuck with whatever fun shit I like.
 

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let me know if you need some a lot nicer looking amal or doherty control levers for the norton(i can't tell which those are)
id be happy to donate to the project
i have not seen a brit bike with welded on lever perch ,they are welded on right ? like a cz
 

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The levers and clip-ons are Manx Norton. The perch is braised on, when prettied up they should look a bit like these!!

DSCF0224.JPG

The rear brake pedal is also manx, should be a forged steel chromed.

DSCF0180 (2).jpg
 

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By the way you want cool fuel not heated. Cool fuel make more power around 2-4% depending on the engine.

A few of the combined fuel and oil tanks in alloy I have seen have two closure plates separating the oil tanks or rather the plates create an air gap, unfortunately alloy conducts heat. BUT glass tanks do not conduct heat well and don't have the air gap separation.

Many early American V twins have combined fuel / oil tanks and have air separation.
 

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Gee, just a guess but if it's a British bike it's probably Lucas built and if it's American built and has Mallory red on it, is probably a Mallory part.
 

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Discussion Starter #12
By the way you want cool fuel not heated. Cool fuel make more power around 2-4% depending on the engine.
Thanks XB the plan is to use everything that's not falling apart. I have no intention to restore the bike, just preserve what's there, battle scars and all. But if I do get stuck for something I'll reach out.

I have done quite a bit of reading on fuel temps lately for my land speed bike, found a lot of information from NASCAR to F1 and a few universities. Biggest gains in cooled fuel are made when using forced induction, naturally aspirated you get minor gains like Steve posted. It's a little hard to see but in the cutout on the tail section is a old Mr. Gasket Cool Can, all the fuel lines and fuel rail are insulated on the Hayabusa IMG_3691.JPG
 

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HOT FUEL i have never read or heard about that being a good thing
except when the carburetor was a wick in a copper tube LOL
I THINK THE BRITS SCOFFED AT THE IDEA OF IT BEING A TERRIBLE THING
my XB33"goldstar"has the tank underside sculpted to clear ther rocker boxes
my buddies matchless singles it's even more extreme
heck the heat will help keep the water out of the gass wont it ? back to your twin
i sure love the look of the swept back pipes !! that design is a real shining example of taking a functioning part and for whatever reason settling on a design that pleases the eyes
these video game apple app device lobotomised, poisoned in the head kids, doing "builds" these days have an alarming penchant for sickeningly . butt ugly, motorcycles.... it is like they are from the planet hideous,
i liked the swept back so much so i put one on my xb and hung the large full radius unit in the rafters
 

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HOT FUEL i have never read or heard about that being a good thing
except when the carburetor was a wick in a copper tube LOL
I THINK THE BRITS SCOFFED AT THE IDEA OF IT BEING A TERRIBLE THING
my XB33"goldstar"has the tank underside sculpted to clear ther rocker boxes
my buddies matchless singles it's even more extreme
heck the heat will help keep the water out of the gass wont it ? back to your twin
i sure love the look of the swept back pipes !! that design is a real shining example of taking a functioning part and for whatever reason settling on a design that pleases the eyes
these video game apple app device lobotomised, poisoned in the head kids, doing "builds" these days have an alarming penchant for sickeningly . butt ugly, motorcycles.... it is like they are from the planet hideous,
i liked the swept back so much so i put one on my xb and hung the large full radius unit in the rafters
Pressurised induction on a 60's Brit!!!!

You are quite right about the engine heating the tank and therefore the fuel but race bikes don't hang around at traffic lights getting to boiling point like a road bike. In fact most of the hot air should be heading through the engine and out toward the rear. Fuel boiling off can be problematic though, rubber carb mounts serve two purposes by isolating the carbs from vibration reducing fuel frothing and secondly heat insulation. You often find a tufnol spacer on a lot of Brits which acts as a heat insulator. Both avoid overheating the carb and boiling off fuel.

When the fuel is cool it is more dense "fact" = a bigger charge, however there is also low temp point at which fuel changes and performance gains start to go the other way due to viscosity change and atomisation issues (I think but I haven't read that book for years). Many race fuels nowadays are blended to be stable across a wider temp range, so we don't worry so much today, that said some race fuels over 105 as used rallying and motoX are gone in a few moments if spilt.

All that said I was at Spa Francochamps last weekend at the ambient temp was 36c (tyres didn't last long about 5 or 6 laps) but whilst I opted for the comfort shade and a cold beer our bikes were covered with blankets to keep the sunshine off the tanks and the fuel cool.

To put fuel expansion into some sort of scale - I run a 42mm Gardiner carb on a 92bore Manx, compression is a fraction under 13:1. The Gardiner carb is flat slide with no pilot system just a wedge needle to meter fuel. The needle is usually set at 5 to 6 turns out ambient 20-22deg C but at ambient 34-36degC the needle is 8 to 10 turns any less and the bike coughs and bags on more than 1/2 throttle. The engine setting remain the same. Humidity plays a part also allowing approx. 1 less turn on the needle when humidity is around 70%.
 

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Discussion Starter #15
I have two good pics of the bike, one in 1965 when Bob Wier the original owner raced it and one from 1974 when Edward Bilton Smith owned it. Some time in the 11 years the oil in the fuel tank was added. After taking a good look trying to figure why the tank was so heavy at first I started to think it was a glass reproduction, Tapping it all over it sounded dull and thick but the sound lightened up as I went up the sides and parts of the top sounded metallic, also there were cracks along the perimeter of the tank on the bottom. On the longest crack 3" I used a small scraper to open it up and what looks to be bondo or some kind of filler started to separate, some of the filler is semi-soft and some is hard. Using a heat gun I start to remove it to see what's going on, the tank has been opened up so far in two places and then sealed with some kind of white sealer. So now I'm going to finish stripping the bottom then figure what the next move is. I'm seriously thinking about removing the oil filler cap, oil/fuel divider and oil vent and putting it back to the way it was (the divider is glassed in by pouring resin in the tank and rotating it). I did not want to go this far but the work done is horrible and the tank is really heavy IMG_20180705_102336872.jpg
 

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cool fuel = more dense fuel = more overall power because you are packing a lot of energy potential into a smaller package. Good for power bad for efficiency. However, if you read up on fuel efficiency technology a lot of the experiments focus on heating and pressurizing the fuel because it atomizes better and requires less fuel overall to cause the same amount of combustion force with less emissions byproduct. So heated fuel = better atomized fuel = more efficiency per charge. But it won't make more power - it just makes same power with less material.
 

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some engines crave and love raw fuel droplets while others want it finely atomized

smokey yunick's engine using very heated fuel and only vapors had internal geometry that didn't like big droplets

read smokey yunick and david vizard's stuff

that norton has no more problem with big chunks of fuel than many flathead engines as long as the ports haven't been opened up the size of a fist

the 'good for power bad for efficiency' mantra simply isn't a valid catch all

an engine that likes big chunks will never be efficient if fed vapors
 

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some engines crave and love raw fuel droplets while others want it finely atomized

smokey yunick's engine using very heated fuel and only vapors had internal geometry that didn't like big droplets

read smokey yunick and david vizard's stuff

that norton has no more problem with big chunks of fuel than many flathead engines as long as the ports haven't been opened up the size of a fist

the 'good for power bad for efficiency' mantra simply isn't a valid catch all

an engine that likes big chunks will never be efficient if fed vapors
All valid points - but the original jist of what I was saying is that a little "hot fuel" from a shared fuel/oil tank isn't harming anything.
 

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cool fuel = more dense fuel = more overall power because you are packing a lot of energy potential into a smaller package. Good for power bad for efficiency. However, if you read up on fuel efficiency technology a lot of the experiments focus on heating and pressurizing the fuel because it atomizes better and requires less fuel overall to cause the same amount of combustion force with less emissions byproduct. So heated fuel = better atomized fuel = more efficiency per charge. But it won't make more power - it just makes same power with less material.
When it comes to old Brit stuff you can theorise all you like. Hemi's like it low down and dirty with wet combustion chambers. And who said flag to flag racing was about efficiency, its about bigger bangs and getting ahead! And if you want to atomise fuel better you don't use Amal carbs.

Back to the top of the page this thread is about a period racing 650ss with gravity fed Amals not an Yamaha R1 with throttle bodies and mapped injection.
 

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some engines crave and love raw fuel droplets while others want it finely atomized

smokey yunick's engine using very heated fuel and only vapors had internal geometry that didn't like big droplets

read smokey yunick and david vizard's stuff

that norton has no more problem with big chunks of fuel than many flathead engines as long as the ports haven't been opened up the size of a fist

the 'good for power bad for efficiency' mantra simply isn't a valid catch all

an engine that likes big chunks will never be efficient if fed vapors
Spot on kiddo!
 
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