Carb valve things

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CPowell1994
Posts: 34
Joined: Wed Feb 14, 2018 8:51 am

Carb valve things

Postby CPowell1994 » Fri Feb 16, 2018 9:25 pm

Little nipples/valves on bottom of carbs. What are these for? I imagine there's a line that's supposed to come from these (mine doesn't have one). This might be rudimentary, but I'm new to carbs/new to older bikes. Any info is appreciated.
Loud pipes save lives. Pissing off everyone around you is just a bonus.

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GeorgeSweety
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Location: UK.

Re: Carb valve things

Postby GeorgeSweety » Sat Feb 17, 2018 3:54 am

Those little nipples are your float bowl overflows. If your carbs get too much fuel going in then this is where the excess fuel will come out, this is to prevent your engine filling up with fuel which can be very bad for your engine. Too much fuel in the carbs can be caused by a sticking float needle or your float levels are set wrong. The large screws on the bottom of your carbs (one on each carb) are your drain screws, if you want to drain the fuel from your carbs or check the fuel flow to your carbs then you undo this screw by a turn or two and the fuel will flow from the nipple.

CPowell1994
Posts: 34
Joined: Wed Feb 14, 2018 8:51 am

Re: Carb valve things

Postby CPowell1994 » Sat Feb 17, 2018 8:23 am

Awesome, thanks for the response. Are there supposed to be lines attached to these, or no? Or are they just designed that way to attach a line for checking fuel flow?
Loud pipes save lives. Pissing off everyone around you is just a bonus.

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GeorgeSweety
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Re: Carb valve things

Postby GeorgeSweety » Sat Feb 17, 2018 9:26 am

Yes there would have been pipes attached when new, this is where you would attach your clear tube when checking your fuel level with the clear tube method.

CPowell1994
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Joined: Wed Feb 14, 2018 8:51 am

Re: Carb valve things

Postby CPowell1994 » Sat Feb 17, 2018 9:54 am

Ok, so if I "T'd" them all together into one line in the middle (open ended) to keep dust/dirt out, would it hurt?
Loud pipes save lives. Pissing off everyone around you is just a bonus.

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GeorgeSweety
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Location: UK.

Re: Carb valve things

Postby GeorgeSweety » Sat Feb 17, 2018 1:23 pm

CPowell1994 wrote:Ok, so if I "T'd" them all together into one line in the middle (open ended) to keep dust/dirt out, would it hurt?


Why would you bother? If one of your carbs had an overflow problem then you wouldn't know which one it was until you pulled the T off. I think that is probably one of the reasons that people never bothered with the overflow pipes in the first place, they were tucked down behind the motor and hard to see if there was a leak. Far easier to see (and smell) if it was dripping over your engine instead of underneath your bike.

CPowell1994
Posts: 34
Joined: Wed Feb 14, 2018 8:51 am

Re: Carb valve things

Postby CPowell1994 » Sat Feb 17, 2018 5:34 pm

Yeah that makes sense. Thanks!
Loud pipes save lives. Pissing off everyone around you is just a bonus.


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