A Carbs a Carb, Dogma is Dogma but still wrong, and an impediment to knowledge Sorry I not educated like you, speak only ozstrlian Use more imagination or ask me? you got me pissed you got a bike runs like shit, because you dont know what you doing you dont understand how shit your ideas are?? And I who had a bike amazing, got no clues??? ok look the challange? put your money where your mouth is? cut your broken valve up? bet is an FCR kehien 41 photos later
great idea? and see if it stops carbs overflowing? its either a fuel pressure problem possibly caused by a vent problem (charcol canister, i didnt have them), or a float valve problem?/ vent the tank? if fuel continues to rum ; has to be float valve problem? either dirty valves or damaged valves, flush them as described? if still leaking, inspect them, and replace, after correcting any float height issues as a cause
But I'll try: Firstly the breather valve is a two part aluminium case hence the joint line around it (When badly made the two parts can come apart fairly easily for a couple of reasons, especially if it gets blocked - internal tank pressure is usually the cause) The valve has a two-way function because inside is a light spring and a small disc. The valve will allow air easily into the tank but will not release tank pressure as easily (hence the hiss as fumes escape when opening the filler cap). The disc is what prevents fuel from surging out of the valve when the bike is being ridden, particularly under braking. The tank pressure should release via the valve at around 4psi - 5psi. There is an arrow on the case to show which way the valve should be installed (pointing away from the tank breather stub pipe). The genuine Ducati one will cost over £50 - that is not the price of a cheap one way air inlet breather valve. If you really need to know, email Ducati in Italy and ask the bloody question like I did. When it comes to siphonic action; someone has obviously never understood how a siphon works. The carb float bowls on the SS are well below the bottom of the fuel tank - the overflow pipes are even lower. The electric pump (3psi - 4psi) inside the tank does not stop fuel from running through it when the ignition is switched off; all that happens is that fuel is not actually pumped. With the tank brimmed or very full there is a substantial head on the delivery fuel line (look at a diagram of what is inside the tank) - that in itself might be enough to start a siphon because the level of fuel is well above the bag filter at the bottom of the tank - all it would take for the siphon to start in that instance is leaking float valves. But when the tank pressure builds for whatever reason ie agitation; atmospheric pressure or temperature and the breather valve doesn't release that pressure at 4psi - 5psi; then the whole fuel system become pressurised; enough to push fuel up the line to the pump and all the way through to the petcock which if open allows pressurised fuel down to the float valves - equally that same pressure in the tank is going back through the return line down to the delivery line. Once the fuel line pressure is on the float valves, if it exceeds 12psi (which isn't much at all) then the float valves can be forced open and the siphon starts. You can easily test at what pressure the float valves will open, by mounting the carbs at the correct angle in a vice; then attach a 300mm hose to the carb inlet tee-piece. Fill the carbs and the hose; then attach a footpump with a gauge to the hose. Push the pump down and watch the gauge so you can see at what pressure fuel starts to piss out of the carbs - because it will; in fact you don't have to see it piss out because you will feel and hear when the float valves open. There's a good reason why Ducati fitted a petcock on the tanks - it's just a pity they didn't fit a proper tap that could be got at without lifting the tank.
Got a bit heated there,by the way I've got an ie but have been working on my lad's '94 monster and wondered why it kept cutting out on me. later I remembered carbys have fuel taps.
Not heated at all by me - more likely despair..... ... just trying to help the OP and educate the Man From Downunder (Men with Hats)
???? lets drop this please, suggest you dont confuse the world any more, or me? OR I going to NUK YOU Ducati fitted the valve for taking the tank off, and the fuel pump to compensate for inadequate fuel height in a 3/4 empty tank?? WHAT DO YOU THINK note the height of the bottom LHS of fuel tank relative to float bowls needed a pump? I have provided a illustration to help you understand what a siphon is
look at my full reply, and clean your vent valve and dont install it the way he suggests hes wrong on that and every other bit of bad advise hope you fix the bike but sadly, taking it to a ducati shop may be a solution, rather tha listening to stuff that will cause more problems. This is so simple good luck
you cant educate me because in my posts I have demonstrated you are; needing help, or work for yamaha, either way I leave my posts standing, but wont reply to anymore of contentions which are not based in fact and are about 90% wrong look my posts, use your brain and apologize for being totally misguided, and I might help you reclaim your gummed tank vent valves, or send them to me and I will consider that attrition for the harm your dangerous misconceptions may cause to our friends with their farting gas tanks, and overflowing carbs and fuel lean farting around SSs caused by your disinformation Believe me best you dont try to educate people with these problems dontttttttttttttttttt stoppppppppppppppp dont dooooooooooooooooooo go turn your vent valve the right way round.
put the vent valve with the arrow pointing to the tank, and stop listening to "old mate" hes not quite right, nor am I, but there no hope for "old mate" he doesnt know anything about Ducatis apparently gets his knowledge directly from the factory race department?
I must say havent stopped laughing all day, this is funny, but in a world where science is wrong because "it doesnt work that way" i genuinely fear for the future,where Ducatis run better with secret pressurized fuel systems enabled by putting the tank vents on BTF
I respectfully suggest that the OP and others with sense ignore The Man from Downunder - he obviously hasn't got a clue and he hasn't even bothered to talk to Ducati Italy about the tank breather valve (among other things). He certainly hasn't consulted other Ducati forums on that subject or a Ducati Trained Technician. I reckon he thinks the tank breather valve faces inwards simply because in the Southern Hemisphere everything is the other way around - including brain wiring.
Al, it is obvious where the considered and sensible advice is on this thread. Breakout's advice comes over as the rantings of someone who has had too much to drink for many of his posts and he seems to delight in winding people up. We should not feed the trolls, no matter how difficult it proves to be
We should feed the trolls IMO - I lke seeing the crap they come out with when it gets too much for them and what dickheads they show themselves up as. I'll bet he has never even seen the pic below or at least bothered to look at it properly.........it is from the parts handbook. See the breather valve? See the join in the case which is nearest to the tank? Well, the little arrow faces the other way from the join, doesn't it?
flow direction has to be toward the tank, test it, after you un-gummed it? The arrow direction doesn't matter, flow direction does. convention is arrow points in direction of free flow. me I wouldnt even look a all this baby stuff, would just test valve and put on right way three weeks ago. maybe according to you Ducati got the arrows on back to front?? https://www.google.com.au/search?q=...x-b&gfe_rd=cr&dcr=0&ei=JcnZWcCJHo3r8wfa0KH4DQ Yes you are right, arrow point wrong way away from tank according to the majority of votes Ducati is wrong according to check convention And I would never have or had these problems because it is all simple shit and I dont invent explainations link http://www.ducati.ms/forums/57-supersport/60881-vent-direction.html
