Hi guys just require a few pointers to my issue Bike cuts out after 15 mins spins over I can hear pump prime and stop I have changed both relays near ecu and main relay near battery. Battery is charging 14v when running 12.4 off standing battery when spins over Had new fuel filter/ seal last year No swirling in tank With tank off there is a good spark I have changed crank sensor and checked gap Last run out ran really well until it died then nothing spins over fine Bike has no cut out switch on sidestand Any ideas?
Does it have the quick-release fuel connectors in the tank? Asking because (some 748 don't), I replaced the connectors in my 916 for the metal versions which were fine for a few years and then one day the bike just stopped on me and I had to get breakdown/recovery to get me home. Then a few days later after disconnecting the tank and finding no fault then refitting everything it was OK again so I went out for a test ride and it stopped again, this time less than a mile from home so I pushed it back. This time I removed the fuel pump housing and found that the internal 'O' rings in the tank connectors had swollen - everybody knows about the external 'O' rings on the hose fittings and these are frequently changed if they leak but the internal 'O' rings are in the tank/female fittings rather than the male fitting on the hose. If these internal rings swell they can block the flow of fuel, more likely on the flow line (M) than the return line (R) due to the way it the fitting works, meaning a complete fuel cut-off which is what happened to me. Removing/refitting the fuel line may clear it temporarily by moving the 'O' ring slightly, at least it did on mine. Good news is that they are cheap enough to buy and easy to replace but the bad news is that you need to remove the fitting from the pump base to do this - and make sure you fit Viton 'O' rings for best resilience to fuel, in fact I think that was the problem with mine - that they were not Viton when I bought them. According to Tom Parkers (a UK supplier of these fittings) the standard versions do not have Viton 'O' rings in them and that, they didn't stock the Viton equipped versions so were special order. Actually when I removed mine, I ended up losing the spring from the release mechanism as it shot across the workshop when I removed the locking plate (removing the lock-plate means you can get a socket onto the fitting rather than struggling with an open-ended spanner which makes fitting them much easier) so I bought a new fitting which was the non-viton type but got some viton 'O' rings to replace before fitting. Of course, I later found said spring but couldn't find it when I needed it! The Viton version has the part number with a 'V' suffix, i.e. CPC-LCD10004V for the male, hose fitting and CPC-LCD23006V for the female, tank fitting or, if in any doubt get some Viton 'O' rings and swap them out - not really a problem for the male fittings as they are just a few seconds to swap but, given the female fittings need to be out of the tank, a little more involved. Can't tell if this is what has happened to yours but, it happened to me and it was tricky to diagnose at the time.
as you discovered, if they are non-standard and not Viton then that is the problem, and quite a simple one, I think most people will have standard O-rings internally although of course it can't be ruled out 100%. I often see people suggest cheap O-rings that say "fuel resistant"... not even Viton sometimes, and it's just a false economy to fit these anywhere on the bike, it really is. . i'm not sure how many things you've tried so far, but will get back with some suggestions if I think of any. The most difficult fault to solve is the intermittent one isn't it? Maybe you could start to prepare to test to work out if it's fuel or ignition to start with, I know there have been similar threads where we've all gone into detail about possibly the simplest way to achieve this, you could take a spare plug with you, and immediately it stops running plug it in and earth it and try churning, for starters. A slight risk involved here, but you could take a penetrating spray can with you, and spray into the air intake, but for no longer than three seconds, and turn immediately to see if you get a cough, for the fuel test. The propellant used on WD-40 et cetera is highly flammable, I don't use easy start or/start ya bastard anymore, because this is also a lubricant and so doesn't attack plastic and things, so perfect.
O/T but I needed a new gasket for the filler cap on my old Guzzi. I couldn't find a ready made one so I bought a sheet of 'rubber' to make a new one from, advertised as 'fuel resistant' but the first time I stopped to refill the tank, it had turned to 'snot' from the fuel splashing on it. Bought a sheet of Viton and it's been fine.
Well finally sorted after taking off tank found one of q/r disconnects not pushed fully home, and the bike seems to running fine just ran for an hour no issues On the plus side a have renewed all relays and a new crank sensor and I felt it to be running lovely Forgot to say it's an sps with 853 kit
Pfm calipers and rotors fantastic brakes The bike was originally rich at louigi_moto_personal bike Nothing left to do just move the regulator rectifier to back maybe The paint is by prokustom all airbrush no decals beyond good and reasonable price
