If I take a bike carb and remove the slider and the Fuel side of the carb does it become a "thorttle body" in principle?

Surely a throttle body is a Tube with a butterfly at one end....

as per Linky to Flea Bay

You will have to fit the injectors somewhere...

Its a zetec head so I still have the sandwich plate for the injectors.

if you fit injectors into your manifold, then i don't see why not.

In theory yes but you wont have a smooth body all the way through as youl have the gap where the slide goes. And as David says you will need a manifold with injector holes.

don't want to take this down the wrong way, but on a bike carb, what does the slide actually do?

like this but the slide is generally operated by the engine vacuum in our carbs with the throttle cable controlling the vacuum via the butterflies.

[Edited on 19/2/10 by cd.thomson]

You can mount the bodies onto a ST170 manifold like this and use the injector pockets in the manifold.

The slide controls the effective venturi size to maximise air velocity across the rev range, i.e.

low revs, small venturi = high gas speed

As revs rise the decrease in pressure in the manifold, allows air pressure under the diaphragm to lift the slide and allow more air in. The drilling to the engine side of the diaphragm seal is connects to the venturi, hence at manifold pressure, the holes at the inlet side of the carb are to keep the underside of the diaphragm at atmosphere.

Stripped carbs have been used as TB's before though, so perfectly possible.

[Edited on 19/2/10 by r1_pete]

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If I take a bike carb and remove the slider and the Fuel side of the carb does it become a "thorttle body" in principle?

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why not just buy these?
linky

perfect for the job.

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Originally posted by r1_pete
The slide controls the effective venturi size to maximise air velocity across the rev range, i.e.

low revs, small venturi = high gas speed

As revs rise the decrease in pressure in the manifold, allows air pressure under the diaphragm to lift the slide and allow more air in. The drilling to the engine side of the diaphragm seal is connects to the venturi, hence at manifold pressure, the holes at the inlet side of the carb are to keep the underside of the diaphragm at atmosphere.

Stripped carbs have been used as TB's before though, so perfectly possible.

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Ok first attempt will be to convert the Bike carbs into throttle bodies. I won;t remove the slider but lock it UP to give a smoother body... and plug some of the wholes......

Alternately what about leaving the the Slide active to the effective venturi size to maximise air velocity across the rev range... so EFI with variable Venturi.....

Yes! that is exactly what you should try to do. The 5PW (i think..) R1 uses exactly this setup, CV throttle bodies.

It should help better atomize the fuel and burn speed (by having a more homogeneous mixture), minimizing ignition advance needed for maximum torque at lower revs.

Could you post a picture of the inside of the carbs with throttle plate and slide held open so we can have some idea of what still protrudes into the airstream?