fireman fez Posted April 1, 2012 Posted April 1, 2012 have a 650 as you know, anyhow its developed a problem that has totally stumped me, starts and runs fine on tick over, give it a little throttle and it starts to miss, give full throttle and it cuts out, tried the coils, carbs (so its not the fuelling), cdi, plugs, off my other 650 to try and have some idea but still the same, would the coil pick up behind the generator cover cause this prob ??? and ideas would be of great help. many thanks Mike
gizmo666 Posted April 1, 2012 Posted April 1, 2012 my friends virago played the same game and it turned out to be the pick up coils test them first before trying anything else
Dickwad Posted April 3, 2012 Posted April 3, 2012 sounds like the main jets, or at least one of them is blocked, have you removed the main jets and jet tubes and blown them out? electrical components either work or they don't, there usually isn't any in between.
fireman fez Posted April 3, 2012 Author Posted April 3, 2012 sounds like the main jets, or at least one of them is blocked, have you removed the main jets and jet tubes and blown them out? electrical components either work or they don't, there usually isn't any in between. put the carbs off my other draggy which are good and still same checked resistance off pick up and thats spot on,
Dickwad Posted April 4, 2012 Posted April 4, 2012 I'm convinced its a fuel problem, not necessarily the carbs, check you have good flow from the tank, check the fuel filter, check the pump is working OK. just out of interest, have you fitted none standard pipes? I did, and had the very same problem, you may have read my last topic. If all else fails you can give the bike to me and i will love and cherish it :babyha:
Noise Posted April 4, 2012 Posted April 4, 2012 Dose it run better with the choke pulled out? fire her up and ride off with the choke pulled out................if this solves the problem them its fuel problems and you might have to re-jet her. Again as Dickwad has asked...have you fitted after market pipes? if so then your fuel/air mixture is out and your prob running too weak so best bet is to also take your spark plugs out and check the colour of them. Black soot is running too rich so you will need to down size the jets or adjust your diaphragm needles down a notch, if they are white then you are running too weak and need to up the main jets and the diaphragm needles. Try this and report back
fireman fez Posted May 5, 2012 Author Posted May 5, 2012 I'm convinced its a fuel problem, not necessarily the carbs, check you have good flow from the tank, check the fuel filter, check the pump is working OK. just out of interest, have you fitted none standard pipes? I did, and had the very same problem, you may have read my last topic. If all else fails you can give the bike to me and i will love and cherish it :babyha: tried that still the same
fireman fez Posted May 5, 2012 Author Posted May 5, 2012 Dose it run better with the choke pulled out? fire her up and ride off with the choke pulled out................if this solves the problem them its fuel problems and you might have to re-jet her. Again as Dickwad has asked...have you fitted after market pipes? if so then your fuel/air mixture is out and your prob running too weak so best bet is to also take your spark plugs out and check the colour of them. Black soot is running too rich so you will need to down size the jets or adjust your diaphragm needles down a notch, if they are white then you are running too weak and need to up the main jets and the diaphragm needles. Try this and report back tried that too, even put standard pipes on,
fireman fez Posted May 5, 2012 Author Posted May 5, 2012 replaced pick up coil with genuine yamaha, its deffo not the fueling, pump, carbs etc as i have taken the bits off a good one and it's still the same, even spraying fuel direct into the venturi's has no effect, i'm sure its electrical, swopped coils, cdi unit, pick up, plugs, kill switch, sidestand switch, clutch switch, this one has got me .
fireman fez Posted May 7, 2012 Author Posted May 7, 2012 guys thanks for your input, i've cured it, and you wont believe what it was, i could write a long list of things i tried, i replaced everything, was about to pull the heads off as a last resort, and thought i would put the air filter on just to humour myself, and FOOK ME it cured it i had cleaned all the jets and totally stripped the carbs as initially it was a blocked main jet, started it up and was still the same why didnt i do that 3 bloody weeks ago, so cards behind the bar guys fill ya boots
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