Vf1000r Carb vent tube

Hi, I wonder if anyone can shed any light on this, the 1985 vf1000r project bike I’m currently building is dripping a few drops of petrol from the carb vent tube, it dosent do it when the bike is running, it does it about 5 mins after I’ve switched it off, occasionally you can see a heat haze coming out of the tube, all the float heights are set at 9mm as per the manual and the fuel pump switches off when the carbs are full.
At the moment I have the vent pipe hanging just below the swing arm, I have just noticed that there is a small plastic hose connector fitted into the top of the swing arm, should the vent tube be connected to that ?


I don’t know why but the gaiter on the bottom of the shock has a pipe that connects to that elbow on the swingarm.
Im still foxed by the fuel drops.

Pete,what are the ID numbers on your carbs?
There has to be some logical explanation for this.
Your float height is 1.5mm lower than most VFs so overflowing should never be a problem
Regards Bif

I can’t remember the carb id numbers off hand but when I bought the bike I checked them out through the data base on here, since my last post I’ve changed the petrol pump, the original was quite noisy, now from cold the pump clicks on a few more clicks than I would like, from warm I stops dead, as it should,
I still don’t think there is any real flooding issue, I’m pretty convinced now that it’s down to the internal diameter of the vent pipe. I fitted a 10mm hose on on it as that’s a snug fit over the breather tube, having looked at the boldor vent pipe, it’s tapered where it fits onto the breather tube so has a smaller internal diameter, which has less surface area for petrol fumes to condence on…

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