SU CARB BOWL TO NOZZLE HOSE
 
One problem common to SU carburetors is the aging and cracking or leaking of the short flexible hoses between the fuel bowl and the nozzle of the SU carburetors.  When replacing these hoses you MUST be very careful to use a thin flexible hose that is fully tolerant of exposure to gasoline.  Failure to pay attention to this little detail can lead to disaster for your roadster.

One product that has worked well for this application is Vitube.  

Physical Properties Type A Type B
Hardness, Shore A 75 60
Tensile Strength, psi  1600 1450
Elongation at Break, % 150 350
Brittle Temperature -30°F -40°F
Max. Operating Temperature 400°F 400°F

APPLICATIONS

Appliances • Automotive Fluids • Cable Jacketing • Chemical Lines • Fuel & Oil Lines • Hot Lubrication • Model Engine Exhaust • Peristaltic Pumps • Seals & 'O'-Rings • Solvents

Information taken from the Vitube web site

Vitube may be found at industrial supply houses and probably through custom hose manufacturers.  I am working on finding a list of places you can order it if you don't have a local source. 

I notice that it is also listed for for use with model engine exhaust.  It is possible that a hobby shop dealing in gasoline engines could carry this product for their customers.

This tubing was available by the foot from

www.mscdirect.com
1-800-645-7270

Product Ref # 7981 4828

I had trouble locating this product on their web site, but Greg Chirpich reported to the Roadster List that the following search sequence will produce what you are looking for:

To find the Vitube on the MSC site, search for:

Gasoline tubing
Then select Hose, Tubing & Fittings (not automotive)
Then select Tubing
Then select Rubber
Then I had to refine the search by specifying maker/brand as "New Age Industries" and specifying material as "Viton".

Usage Note:

Vitube is thinner than the original float bowl hose, so it will kink easier. Cut it a little longer rather than shorter.  You can use your old line clamps or go to Home Depot and get some springy things that they sell in 'plumbing'.
 
Thanks to Datsunmike for this information