tripping over the things you lot are! The tricky thing that adds to the cost of that pile of bits is those laser etched numbers pretending they're genuine factory corse parts, otherwise it's just an M10 hose spigot, a one way vent and a motion pro bottle and some tube. Granted, very nice spigot though
its a real pity Harris is gone as they used to do those one way fuel breather valves by the bucket load. If you want authentico Italiano they probably raided the parts bin and went for the SS/SL / 851/888 breather valve 59320041A.
i think when i did this with my carbon tank is used pn 59320041A from a 900ss and a spigot from another model that escapes me at the moment
It builds up quite a lot of pressure when the fuel warms up. My Beater tank made a proper bang when you opened the cap after a while. Ended up drilling through the valve to retain the original look.
Maybe I've got this wrong... but isn't that the point ? It lets out excess fuel vapour pressure ? Is your valve on backwards ? My 888 flowed OUT... not in
the OEM fuel tank uses the oem filler assembly to vent rather than the through a vent pipe and valve like the older bikes. The beater tank won't have those internal pathways, and the race filler caps don't have any contingency for bleed-off unlike the oem assemblies do. They're just a ring seal and a cap, which means that there's nowhere for anything to go unless you introduce an auxiliary venting system like on the 851/888/900ss etc. Its the mistake lots of people make when they go and buy a cheap and cheerful race filler and then wonder why the bike suddenly gets fuel starvation as the cheap race fillers do a great job of blanking off the pressure bleed-off port. Also, don't forget the '49r has it to homologate it's use on the WSS kit, which is why the regular xx9 didn't get it.
I guess it depends on the valve, mine definitely wasn't two way. If I were to put it the other way around there would be a vacuum in the tank when fuel is used.
