Reserve fuel tap

[b'knighted]

The right side holds more than left as it is not reduced by the front carb cutaway. A weir tube on the left tap can be used to increase the depth of reserve but will cause the fuel in below the tunnel height on the right to be inaccessible to either tap. When the main (left) runs out you go on to reserve (right). When that runs out laying the bike over to the right, or in extreme situations whipping the tank off to lay it on its right side gets the final few miles of fuel to the reserve tap. I will concede that flat out running on a twin may require both taps but fitting a big bore main tap to preserve the reserve would be worthwhile for road riding.

 

[roy the mechanic]

Both of my taps have had a 1/4 drill through them to ensure that my high speed running is not impeded, after all it was the "fastest standard motorcycle in the world". It is a rare day when a crotch rocket gets past me! The breather in the cap has also been opened-out to suit.

 

[bmetcalf]

I have Vinparts' leak-proof taps (gas valves) and I use the right side as my reserve.

 

[A-BCD]

I don't need no stinkin' reserve fuel tap.............

 

[clevtrev]

Both of my taps have had a 1/4 drill through them to ensure that my high speed running is not impeded, after all it was the "fastest standard motorcycle in the world". It is a rare day when a crotch rocket gets past me! The breather in the cap has also been opened-out to suit.

Did you open up the hole in the mainjet, as well ?

 

[A-BCD]

I've drained 2 gallons from the tank through 1 tap with the standard cap in place in about 2 minutes - seems the flow is quite adequate ??

 

[b'knighted]

I've seen your big carbs, What speed were you doing at the time?

 

[A-BCD]

I've seen your big carbs, What speed were you doing at the time?

That would be telling...................... ( by the way it was on the A twin which has smaller bore taps than the B )

 

[davidd]

I've drained 2 gallons from the tank through 1 tap with the standard cap in place in about 2 minutes - seems the flow is quite adequate ??

That's the way to do it! I did the test aslo on the racer. Once with the cap on and once with it off to see if there was a difference. There was not. 1.25 GPM, so I decided that was all I needed for one tap. The tank holds 1.54 gallons which at 38 mpg under full throttle at Daytona is enough to do any practice or race.

David