Exhaust Flexible exhaust pipe



I have done my searches, but I can't find any info on the flexible pipe used in the Hornet:


Does anyone have any ideas on what kind of pipe to use?

I have thought about perhaps using the flexible ducting they use for electrical cables, but I am worried about exhaust leaks? Perhaps I could cut the exhaust after the downward bend put in the electical flex duct on with a clamp, then mount the rest of the exhaust pipe next to the sprocket?

Let me know if you have better ideas?
I believe that hornet made his pipe from conduit
it can be welded, but you need to grind off the galvinizing before heating or it will give off hazardous fumes
(bye-bye brain cells:rolleyes:)
I always thought using fexible copper to get the right config, and then transfering that shape to steel would work well
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FYI - Flex pipe adds restriction to the exhaust (as opposed to smooth exhaust pipe) but it does make exhaust routing easier..
I looked for flexible gas pipe, but the only size that I could find is 3/4" - with an inside diameter of about 1/2". The electrical conduit comes in larger sizes.

I guess I can weld it if I have to - I just liked the look of the flex pipe.

How much extra restriction would we be talking about? Enough that it would matter?
from several years of auto-exhaust experience: some flex tube can actually work to further "restrict" your exhaust...turbulance from the ridges hampers the flow.

i think "hornet" used more of a smooth-bore style of flex that prolly works ok...but if i needed an easy but nice-looking custom pipe, i'd go with conduit.
Flex pipe and.......Fishtail??

Hi gang, that looks to me like the traditional Whizzer flex-pipe, and fish tail used in the kits prior to 1965.