More on carb swapping

[pggg]

Here's a cardboard box of trouble



there's one set of 38mm mikuni CV flatslide GSXR750 93' and some modern 2003 keihin 37mm CV flatslide downdraft R6's, the R6 airbox best stays used with the R6 carbs, I've already hacksawed down that airbox so that's the end of any RAMAIR system, just no way in hell will the whole shebang fit the XS11 without changing the whole bike, frame and all. Cut down, it'll fit as a conventional airbox, it has a large volume too

For manifold rubber, thick flexy commercial fuel hose is smooth inside and the right inside diameter - but is it heatproof enough? Radiator hose is of course not much use as it swells up in petrol, alloy pipe(curved) is another choice.

Those particular slingshot carbs have 117 main jets, the R6 carbs have 152.5 mains and 36 pilots, still haven't got any factual answers on whether the downdraft keihins will actually run as sidedrafts, although there seems to be TWO different float level lines on the carbs at different angles that co-inside with 45 deg lean, but I might be clutching at straws, but we'll see...

[Pat Kelly]

XS750 and 850 (triples) use rubber hose as carb holders. Probably too small diameter for your purposes.
Do you think they get that hot?

One thing that has always baffled me. Why is the intake at the rear of the head and the exhaust at the front? Seems like if it was reversed there would be a straight-through flow to the whole process. Hang the carbs out front, scooping in copious volumes of air, mix in some fuel, burn it, then send it out the back on it's merry way.

[pggg]

Here's the XS11 manifold, fits that hose snugly, for a perfect flow the alloy probably needs planing down to the first lip, and the second lip needs smoothing out with sandpaper too.

[pggg]

Pat, yeah the intake in the fairing nose, V-max has scoops too

[DiverRay]

pggg,
That looks like marine fuel line. It will work for the intake, as the heat won't bother it. It has been designed to NOT BURN in a marine environment.
Ray

[tjfisher30]

confused

ok pggg i get what your trying to do but im looking at you carb holders and they look metal not rubber is this true?

[skids]

Why would something burn in a marine environment? Enquiring minds want to know!

Originally posted by DiverRay
pggg,
That looks like marine fuel line. It will work for the intake, as the heat won't bother it. It has been designed to NOT BURN in a marine environment.
Ray

[DiverRay]

Skids,
ALL fuel lines in a boat MUST be flame proof for 20 minutes. That is why if you look at the picture, there are multiple layers of reinforcement in the hose. The rubber compund on the outside is designed NOT to burn easily, just in case the deck hand tosses his cig. butt into the bilge full of fuel from the leaky hose. The inside of the hose is the smooth, soft, seal against almost anything rubber.
Ray

[pggg]

Re: confused

Originally posted by tjfisher30
ok pggg i get what your trying to do but im looking at you carb holders and they look metal not rubber is this true?

tj, XS11 rubber boots are metal and rubber in one, the metal one's peeled. "...flameproof for twenty minutes..."Damn I'll only be able to ride for twenty minutes then... just jivin' - nah it's a serious chunk of industrial hose, 3 layers of fabric , 3 layers of rubber and spring steel coils thru it, bends without distorting inside.

[pggg]

that's the inside measurements, different from stock where the measurements are equal right thru, factory technicians would probably have a fit..

[GNEPIG]

.. the turbulance from the steps could cause the fuel/air to mix better and the ventury looking part, could cause the mixture to speed up and compress some what.
you wont know til you try.
you could get an idea of how it will look by setting up your carb in the vice and blowing smoke through the carb and manifold setup, like a wind tunnel. this will give you a look at what kind of vortex the step open will make and if it will choke the flow or not.

[pggg]

GNE with a bit of luck(err... make that a LOT of luck) - that funnel shape might equal the 34mm carbs' low torque effect - and still give the 37mm carbs' top end... but then again it might not...