Breather pipe question

[oscarbadgerboy]

Hi Newbie to the site and to VFR 400's only had it 2 weeks and already done 800 miles, love it.

I have done all the usual service stuff and decided to do the valves. Upon re-assembling I have a breather pipe drain pipe which I can not recall disconnecting. I suspect it has been disconnected for a while but it could be me.

The fuel tank breather pipe runs under the inlet for the air filter and connects to a "T" piece roughly the same location as the choke lever. The pipe then runs down to the bottom of the bike as a drain.
My question is the other end seems to run across the back of the carbs in the little bendy clips and I have no idea as to the location for connecting this pipe.

On my fuel tap I have the main fuel pipe and two smaller spigots, one of these smaller spigots is next to the main fuel pipe which is where my vacuum pipe is connected and the one facing down to the ground has nothing on it. This is where I think it would go in case the vacuum stuck open so the tank would vent below the engine.

This pipe though is bigger than the spigot on the bottom of the fuel tap.

Any ideas or help would be appreciated.

Regards Dave

[Deviant400]

i think on mine the tank breather joins the T-peice, one end goes to the under side of the bike as a drain and the other end goes around the carbs and under and sits between the cylinders unconnected , thats how it was when i got my bike , remember having this problem ages ago, i just left it how i found it , never had any probs

[oscarbadgerboy]

Hi thanks for the reponse,
When I took the carbs off I do not recall disconecting this pipe so I feel it must have been left loose for some time, however I now do believe it is a drain from the fuel tap and I think that possibly my vacuum pipe is connected to the wrong spigot on my fuel tap.

There is a post called "numerous problems" which quotes this

One - leaking fuel tap. I had the fuel hose on the correct spigot from the tap, and the vacuum hose was attached to the spigot facing directly down from the tap assembly rather than the one facing to the front of the bike as suggested by the Haines manual

If this is correct then my vacuum pipe is on the wrong spigot which I would need to swap over, also can anyone confirm if the other spigot is a breather/drain for the fuel tap or just a not required

[arsey30]

NC30?
The tank drain hose connects to the bottom of the air box and terminates near the side stand mounting.
The tank breather runs under the airbox inlet and into a T piece near the coil, the outlets then run down by the generator cover.

The tap vacuum hose fits on the outer forward spigot, the inner [middle section] spigot pointing downwards is the breather and has no hose.

[oscarbadgerboy]

Thanks arsey30 for clarifying about the fuel tap, At least my set up is as it should be, I still have one question unanswered.
You said "The tank breather runs under the airbox inlet and into a T piece near the coil, the outlets then run down by the generator cover."

What I want to know is where does the other end of the pipe from the t piece go. Being a T piece there are three ends.
I know one goes to the tank breather (i have this)
One runs down to the side stand as a drain. (I have this)
I still have a pipe that I can not see what it connects to which is the third pipe from the T piece.

[lizard821000]

does it not connect to the small airbox sub filter?

[arsey30]

The 2 outlets from the T piece are open to atmosphere and do not connect to anything, they can both be run down the left hand side of the engine.
The top end goes on the tank breather valve spigot.

[arsey30]

Does this help.

[Neosophist]

The 2 outlets from the T piece are open to atmosphere and do not connect to anything, they can both be run down the left hand side of the engine.
The top end goes on the tank breather valve spigot.

^^ This! :)

I think the original routing has one running down each side of the bike but it doesn't really matter where you run them, my setup is just like the one arsey30 has suggest, they both run down to by the genny cover.

Bike runs like a swiss-watch too.

[oscarbadgerboy]

Just writing to say thanks for the help, after I saw the picture from aresy30 it all made sense what the others had said as well.

Much appreciated
Dave