I’ve got an 02 Cali Ev, it has one of those flush filler caps. I have a leak which appears to emmenate from the alloy surround that is retained by several small allen bolts. It started to leak when full and when left on the sidestand. I’ve taken it apart and sealed it with some fuel proof sealant from halfords. However, it is no better. I’ve re-checked the allen bolts which were pretty tight, and I’ve tweaked a couple of the bolts very slightly. They are certainly as tight as I dare. Hopefully, the problem is now resolved, but I wondered if anyone had similar experiences and/or solutions?
When you fill up a tank the fuel IS cold the engine warmth even the ambient temp does expand it morethan you would think also filling it then popping it on a side stand does allow fuel to get out through the breathers.
When on the V1000 IF I am going on a long run I will brim it and get out of the fuel station as quick as poss.
In normal use I pop it onto the sidestand and only fill it to the bottom of the tube in the fuel tank.
Yep, i had the same problem on my EV, especially noticeable if you have it on the centre stand to fill it completely and then push it away from the pumps and shove it on the sidestand. Mine used to pour out. It had nothing to do with the area that you have been working on. Mine was simply the rubber o ring on the cap. I took it off , cleaned everything underneath and then put it on reverse side up to give a different mating surface. Mine remained leak free after that. Darryl
Shouldn’t any excess/expelled fuel make it’s way down through the drain tube that runs through the tank and ends up behind the gearbox before it weeps through the filler seal?If it’s not then maybe the tube itself is blocked - usually the metal section through the tank - and needs a ream through with something suitable.
on warm days I get my nuts degreased if I brim it!!! thank god they are few and far between here. Its a guzzi, of course the overflow pipe doesn’t work.
if you look in the tank there is usually a metal slieve ( from the cap mount down) the bottom of that is the max level your supposed to fill to.My T5 is the same , brim it and it poors out on the side stand or worse the heat of the engine expands the fuel and it poors out 
I’ve only filled it to the bottom of the sleeve and unfortunately it still leaked. Incidentally, there’s some plumbers seal/exhaust putty type material around the top of the inside of the tank. I assume this wasn’t there when it left the factory, so perhaps this problem is not new and a previous owner had a problem?Anyway, I’ve tried DazGuzzi’s suggestion of iinverting the cap seal and then leant the bike over as far as I dare and it seems to have worked?? However before I tried this I discovered drops of condensation/petrol on top of the petrol cap and surround (this time the bike was level and on the centre stand and inside). I’ve never noticed this before and I couldn’t make up my mind whether it was condensation or petrol, so when there’s a little less fuel in the tank I’ll have it off a check the vent as also suggested.
test it with a match