No that's not right and probably the cause of your issue. The breather on top of the tank sounds faulty, which will stop fuel from entering the carbs.

So i tested the tank by putting it on a few bits of wood to raise it up and collect the fuel in a tub underneath. Got a long vacuum hose and positioned myself so i could suck on the hose, operate the tap and open the fuel cap whilst watching the flow rate.

If the tap is open and the fuel tank cap is closed, eventually the flow stops.

If you re-open the tap at any point the fuel flow starts again.

Keep it open and it just keeps flowing.

So, looks like the breather system. However, i have poked stuff down the holes, sprayed brake cleaner down there and blown through them. The pipes don't appear to be blocked.

Now the seal on the fuel cap seals on the rim inside the tank itself so the fuel cant escape. the breather hole and the over flow are external to this seal. So how does the breather holes work?

It's a one way valve.

You should be able to blow air into the tank via the breather but not suck air back through it.

If you can't blow air into the tank then it's knackered.

I think I have a spare somewhere if you need/want it

I win!

vfrman wrote:I win!

Haha

bikemonkey wrote:It's a one way valve.

You should be able to blow air into the tank via the breather but not suck air back through it.

If you can't blow air into the tank then it's knackered.

I think I have a spare somewhere if you need/want it

Where would i find the original one to get it out? Does the tank come apart? (opens search function)

It's the silver thing at the part of the tank closest to the throttle, has a tube coming out of it going to nothing.

This is an NC35, not an NC30. This tank doesn't have that feature, at least not externally.

This is my tank.

Wheres the valve?

Forgive my shit ability to read thread titles....

Here's the parts fiche, no idea where it is though.

http://www.cmsnl.com/honda-rvf400rr-nc3 ... ml#results