My Cool 750 Commando

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ok tx!

ludwig said:
I put the flange nut on the mainshaft in my lathe and then cut it straight , so that it will hold the clutch centre square .
Is that clear ?
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needing said:
Tuning my Norton carburettors - low cost and still reasonably low tech - better than plug chop.
Using an old header pipe, I fitted bungs for a k-type thermocouple and an oxygen sensor.
These connect to exhaust gas temperature and air:fuel ratio gauges respectively that mount at the handlebars. The other demountable gauge at handlebars is a vacuum gauge (a permanent oil pressure gauge is fitted through the yoke shaft).

The balance tube is blocked so only the LH cylinder is assessed for carby tuning.
Assessing the carbys is done on-road under real conditions and adjustments to jetting, needle heights, etc is done in-shed (although idle mixture can be reset at any static moment). When tuning is completed the RH carby is balanced and settings matched to LH carby.

Tuning completed, the shiny pipe replaced, the gauges removed, and the bike reverts to a standard looking Norton (to meet state 'historic' registration requirements - about 1/3 the fees)
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Do remember to look where your going in between looking at yer gauges old chap!

I notice you have an oil cooler too, how have you plumbed it in? I'm currently toying with the idea of fitting one in the rocker feed circuit, thinking it will help cool the head.

I'm thinking the head on my 10.5:1 CR, 850cc, which is essentially the same design as that on a low CR 500, might appreciate the help in expelling heat...
 
needing said:
Hi.
I found inspiration from Jim Comstock's use of the frame tube as a fuel tank for his fuel injected bike.
The attached sketches are for use on my standard Roadster set-up using twin Amal carburettors - RH saddle is first consumed until empty, then the LH saddle is used and the tube fuel then gravity feeds to the carbys until gone. Total fuel load will now be 11 litre in my Roadster tank with about 2 litre extra in the tube (18% fuel increase).
However, if tank and tube are both empty, a problem that I perceive is how to fill the frame tube without engine vacuum to drive the fuel pump (unsafe to have the bike running while filling at the servo). I also ponder having the tube fuel shut-off valve manually switchable so I can provided pumped tank fuel to the carbys at wide open throttle.
Please analyse the sketches and provide constructive feedback if I have overlooked anything. Thanks.
This is conceptual drawing so I have not drawn filters so as to improve clarity.

My Cool 750 Commando


My Cool 750 Commando
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An Interstate tank is about 20ltrs.. Seems a lot easier to me!!
My Cool 750 Commando
 
Not sure I follow why you feel you need a fuel pump and all that extra switching. Maybe I'm stupid or missing something but the tube is low enough that you should be able to tie it directly to the main tank and feed fuel through the tube for both it and the main tank. Maybe air venting is the issue...but wouldn't the tube vent through the tank if they are tied together? Otherwise what you have drawn should work...just seems more complicated than it needs to be.
 
needing said:
dennisgb said:
Not sure I follow why you feel you need a fuel pump and all that extra switching. Maybe I'm stupid or missing something but the tube is low enough that you should be able to tie it directly to the main tank and feed fuel through the tube for both it and the main tank. Maybe air venting is the issue...but wouldn't the tube vent through the tank if they are tied together? Otherwise what you have drawn should work...just seems more complicated than it needs to be.
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Good point Dennis. I based this design on comnoz stating that he had in-tube fuel heat problems but now I think about it - why/how? and why more than the tank itself.
Also, gravity fill problems? Time for a review and maybe back to the drawing board! I'll protect for this design just in case. :idea: Thanks.
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I think part of what Jim is dealing with is the high pressure pump to feed the fuel injection...but I might be wrong. On a carburetor bike you wouldn't have that and gravity should work...it fills the float bowls...why not the tube? But maybe I'm missing something...thought about air lock in the tube but think that would just bubble back.
 
hobot said:
Due too comnoz FI needing hi pressure he rigged a low pressure pump to feed spinal tank the high pressure pump mounts to and draws from with bypass return line to main tank for the pressure flow the injectors reject. Not applicable w/o FI and therefore better to use frame for OIF to free space to tuck an air separator out of sight or put in air power submarine in like Peel.
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:D :D :D :D
 
A lot of very clever people on here...my brain is frazzled trying to make it
make sense. Glad I am in low tech chain.

Have a good new year all of you

Andy
 
Perhaps the ultra low tech Bunsen valve would be applicable? Although the image shows an open slit, in reality it is simply a slit in the tube that remains essentially closed until a pressure differential exists causing minor flexure of the slit area.

My Cool 750 Commando
 
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