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Bike Carb Help
Dooey99 - 4/3/13 at 06:56 PM

im no expert on bike carbs so could someone please help me with these please...

SOMEONE HELP PLEASEEEEEEEEEEEEE


[img] bike carbs 1
bike carbs 1 [/img]

i believe the pipe running along all 4 carbs at the bottom of the picture is for the fuel to go in
and the pipe at the top of the first picture is something to do with the choke and also the pipe in the bottom picture is to do with the choke!!!

[img] Bike Carbs 2
Bike Carbs 2 [/img]

r1_pete - 4/3/13 at 07:34 PM

The pipe you say is fuel in, is the carb heater circuit.

The pipe at the top of the 1st picture is fuel in.

The pipe in the bottom picture is a vent.

[Edited on 4/3/13 by r1_pete]

myke pocock - 4/3/13 at 09:12 PM

Yep pipe in bottom picture is the vent. I have bike carbs on the Skoda trials car and have the small filter from the bike fitted. (little plastic box with a foam insert in my case)

Slimy38 - 4/3/13 at 09:36 PM

They look like the same carbs I have on my 600cc Yamaha?

The choke is a mechanical device rather than a pipe, if I remember rightly it's the bronze coloured bar on the bottom of the first picture (the bit with the spring on). You can just about see the brass coloured cable clamp between carbs 3 and 4 on picture 2.

For reference, I believe the last pipe that comes from dead centre on pic 1 and disappears off to the bottom right should be the idle control, with a small white plastic knob on the end.

[Edited on 4/3/13 by Slimy38]

Dooey99 - 4/3/13 at 10:23 PM

Told you I was no expert

So how do I plumb these in

Dooey99 - 4/3/13 at 10:28 PM

The heater circuit i mean, do I need it? And how does it get plumbed in?

Dooey99 - 4/3/13 at 10:37 PM

And here's another stupid question... The butterfly's are controlled by a cable or 2 cables depending on setup, but how do you control the plastic slider that moves up and down and controls the fuel? Or does that operate under like vacuum once the engines fire up?

Charlie_Zetec - 4/3/13 at 10:40 PM

Don't bother with the heater pipework, just block the ends off. These are only used on the bike for very cold mornings to stop "icing" of the fuel with air forced in. But I would advise on attaching the choke via manual cable for cold starts!

Dooey99 - 5/3/13 at 07:48 AM

Top lad! Is the choke the sliding bar that looks gold in the bottom of picture one? Or is it the short 8inch cable already attached?

Slimy38 - 5/3/13 at 07:56 AM

quote:
Originally posted by Dooey99
Top lad! Is the choke the sliding bar that looks gold in the bottom of picture one? Or is it the short 8inch cable already attached?


As I mentioned in my earlier post, the choke is the sliding bar (although I called it bronze rather than gold!). The short 8 inch cable is the idle control. Keep that one accessible, but you very rarely need to change it once you've set it right.

With regards to the heating circuit, it's useless even when used on a bike. You don't even need to block the ends off, it doesn't go anywhere.

puma931 - 5/3/13 at 08:39 AM

I used a classic mini choke cable cost £5 on Ebay

quote:
Originally posted by Dooey99
And here's another stupid question... The butterfly's are controlled by a cable or 2 cables depending on setup, but how do you control the plastic slider that moves up and down and controls the fuel? Or does that operate under like vacuum once the engines fire up?

Dooey99 - 10/3/13 at 03:29 PM

thanks for all your help sorry im a pain in the arse but does the vent pipe need to be connected to anything? should i put a small filter on it? and how do the plastic sliders work?

Dooey99 - 10/3/13 at 04:07 PM

and is there anyway to balance these carbs? or do i need to drill and tap the steel inlet manifold i am making?

puma931 - 10/3/13 at 04:43 PM

quote:
Originally posted by Dooey99
thanks for all your help sorry im a pain in the arse but does the vent pipe need to be connected to anything? should i put a small filter on it? and how do the plastic sliders work?


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