On my beta evo 125 2012 one of my carb breather pipes goes vertically upwards and terminates near the fuel cap under a plastic shroud which houses electrics and the throttle cable. Should this be going in this direction or should it terminate near the swingarm like the other carb pipes. Or is this a breather pipe a d the others are overflow pipes. With the pipe running down to the carb it just seems like water could be drawn in when I wash it. Any ideas ? I've just had to strip the carb after washing the bike for the first time. Bike is new to me.

Regarding  the connection at the right hand side of the carb, the horizontal one goes downwards and the vertical one is the vent which on your bike is led up inside the side panel.  An easily available petrol cap vent can be fitted on the end to prevent the direct ingress of water. 

On later models, the vent pipe was run up the hollow frame section, so that the end is up above the highest opening so well protect from direct water.  I would route it that way. If your tube is rock hard, Splat Shop has Keihin bits including the overflow and vent pipes.

See attached pictures.

Carb vent tube routing.pdf

1 hour ago, overdale said:

Regarding  the connection at the right hand side of the carb, the horizontal one goes downwards and the vertical one is the vent which on your bike is led up inside the side panel.  An easily available petrol cap vent can be fitted on the end to prevent the direct ingress of water. 

On later models, the vent pipe was run up the hollow frame section, so that the end is up above the highest opening so well protect from direct water.  I would route it that way. If your tube is rock hard, Splat Shop has Keihin bits including the overflow and vent pipes.

See attached pictures.

Carb vent tube routing.pdf 571.14 kB · 5 downloads

Many thanks for your detailed response. Very helpful. I will have a look on my bike later and see if I can route it through the frame. Otherwise I will get a petrol cap vent.

Gaz

I had a look on the bike and I could feed the pipe inside the frame for s bit more protection. However I would have to shorten it quite a bit as the void doesn't go all the way up to the fuel cap. Shortening this shouldn't affect carburetion should it ?

Whatever length will not affect the carburetion and the up through the frame routing is the neatest solution and best protection. Make the run similar to the 2nd picture, push the tube up inside the frame until it stops, estimate how much to cut off the end and cut at an angle so that even if it comes up against a flat face, it cannot be blocked. Next time you remove the carb for cleaning, it comes out with the carb, and you just slide it back up the frame when refitting.

9 minutes ago, overdale said:

Whatever length will not affect the carburetion and the up through the frame routing is the neatest solution and best protection. Make the run similar to the 2nd picture, push the tube up inside the frame until it stops, estimate how much to cut off the end and cut at an angle so that even if it comes up against a flat face, it cannot be blocked. Next time you remove the carb for cleaning, it comes out with the carb, and you just slide it back up the frame when refitting.

Nice one. Will do just that