bought bike of a guy in Sydney 4 months ago with intention to convert it to a supermoto ran fine for the first 2 months not a beat skipped, then one day filled it with fuel (as tank was running low) then the bike proceeded to not run reliably. NOTE THE PROBLEM GOT WORSE AND WORSE AS I RAN IT MORE AND MORE engine cannot maintain idle and will eventually stall sometimes straight away after starting sometime 5 seconds after sometime need to blip throttle to get it started the only way to build revs is to blip/jerk the throttle constantly slowly gaining revs and cannot reach maximum revs most revs it seems to get is about half throttle then it backfires pop pop pop the first mechanic suggest it was a clogged injector so he did what he did and charged me ran fine when we started it the half way home about 5 km away form mechanic the same symptoms would occur...fml managed to barely get it home mechanic said he pick it up in the afternoon but never came called him multiple time throughout 2 weeks to see when he would come pick it up long story short he never picked it up so i ave up on him and called a husqvarna mechanic he told me it sounded like a efi fuel pump problem so i sent it too him to the other side of Sydney called me back a day later said it was fuel pump problem and that he ordered one from California and that the bike needed a major service and fork service and seal replacement all good service it change the seals and oil picked the bike up on a Thursday ran AMAZING for the whole weekend up until Tuesday afternoon lower tank was low so filled it up with fuel aaand again same symptoms as first breakdown have tried the TPS reset multiple times have tried draining fuel and fresh fuel twice will upload a picture of the invoice from the mechanic as hes done quite a few things to it and two YouTube video of me trying to start the bike and get it running thank you for any help. View: https://www.youtube.com/watch?v=nerXHIjR7dM View: https://www.youtube.com/watch?v=PAdzyRI2N7Q
update just found traces of dirt in both upper and lower tank how do I go about cleaning the fuel tanks out
When bike acts up unscrew gas cap and see if your vapor locking. You'll hear a loud sucking sound when removing the gas cap. Mine did this and I replaced one way valve and it solved the problem. Sometimes the one way valve failes causing bike to vapor lock especially after filling it up. As for dirt in fuel tank it's either pull em and clean em out or you can run a inline reusable fuel filter and clean it often until grime is gone. Also you could disconnect fuel line put some gas in bike slosh it around and drain to try and eliminate some of the foreign bodies. I thought Ziptyracing had inline filters but I'm sure others make them too
Yeah, i agree with Teambowles- it's probably your 1-way check valve on your tank vent line. In the US these things are green and white (and actually they're a 2-way valve... it takes a little tiny positive pressure to overcome the spring) they fail quite a bit. the gas cap test will tell you. A full tank will start acting up sooner then an emptier tank. good luck.
no water was found in the tank. what i did find was clumps of dirt/mud, no rocks. managed too clean both upper and lower tank by flushing them with A LOT of water, then flushing them with mentholated spirits to get the water out and dry them out. petcocks were jammed with mud/dirt too as before i cleaned them they were nearly impossible to fully open up, they fully open fine now(cleaned with water then mentholated spirits) this seemed to fix all the problems, as when i put the bike back together took a few turns to get some gas in her then it ran good, better than before. took it for a ride around the area and dint skip a beat. tried to start it the next morning (Monday) and bike was difficult to start or keep running and backfired, same symptoms as before. fast forward to today tried starting it without removing gas cap didn't start, removed the cap and heard a hiss noise. not sure if vacuum or pressure but the bike started and ran fine. will do more "experiments" with the gas cap over the week. will see how much a new 1-way valve is. thank you so much for the help guys. one of my friends kept repeating to me that it was some minor issue screwing me around hopefully its just the vacuum problem.
route your vent hose up to the neck area then down (yeah, it's a long run) and throw the check valve away; maybe put a loop in the hose even. If you do run the valve, make sure it's orientated in the right direction (easy air draw into the tank, slight hard air pressure out of the tank.) you should never hear a hiss really when you turn the cap on a dirt bike. but small positive pressure won't hurt too much; slight vacuum will screw things up. IF the bike's tank held (+/-) pressure for days- then started and ran fine when you released it: you found your problem. Your tank vent isn't right (it's likely the check valve) that is a lot of dirt. IIRC, there is a screen on the bottom of the main tank. The header tank should always be full. If it does it again, take a fast look at the header tank and see if the level is low (if yes: not filling fast enough from the main tank)
The vent hose should run briefly higher than the gas cap when not using the 2-way valve. Using the 2-way valve allows the vent hose routing to be lower than the filler neck along it's entire length without losing (much) liquid. It also allows a slight suction on the vapor canister (which you probably don't have) without drawing in liquid fuel. For a simple device they have a high failure rate, too. It may not be causing your current problems but it will someday.
update unscrewed the gas cap didn't hear a hissing noise, must be no vacuum. tried starting the bike and couldn't even get it started this time. and it threw a code on the dash "102" anyone got any ideas?
Don't know the 102 code probably gonna have to take it to someone who can read and reset code. Depending on what the code is it may help you solve your issue. Still sounds like a fuel issue to me but check all fuses and electrical connections for mud or dirt like what you found in your tank
yes. you've been working on the fuel system, so now make sure everything works (pressure, spray etc) and that you've purged the air. gas cap: i was referring to your previous observation: go slow, one thing at a time. Try spray starting fluid in the intake to confirm you have a fuel problem.
