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Gpx250 problems - help :(

Discussion in 'Bling and Appearance' at netrider.net.au started by sparz, Oct 28, 2009.

  1. Hey guys,

    Iv got a 2005 gpx250. I've had a couple of little weird problems with it. My first problem (happened a few months ago) was the bike was sometimes losing power. Id be happily doing 80km/hr, then all of a sudden id just fall to about 40km. Id wait a few seconds and then itd be back to normal again. I took my bike to a mates house and we pulled the bike apart and emptied the fuel. It was fine for about another month, then happened again. We pulled it apart again and cleaned out the fuel ?float? (i think). Since then iv put only premium fuel, and i refill the tank at about 250km - just in case (seemed to happen when i had about 1/4 tank left)

    So...since then i havnt had any problems with loss of power - but do u think its to do with a fuel line or there needs to be enough fuel in the tank for some kinda vacuum system to work? Or problems with the carbys?

    The first time we pulled the bike apart one of the spark plugs was pretty wrecked... the tip was chipped.

    Anyways, now iv got this clunking noise. I can hear it in first and second gear while im accelerating. Its an on-going clunking sound with regular intervals. Im really thinking about taking it to a mechanic, although all of this happened a few weeks after i spent $500 getting a 'major service'

    any ideas would be great - thanks
  2. Should get at least 300km until reserve, 350 - 400km average. When it's starved of fuel it will act the way you describe. Maybe the main feed is sitting too high or is clogged somehow - does it continue to lose power when you flick it over to reserve?

    The clunking might be the clutch basket.
  3. Yo;

    Was it raining when you lost power??

    Remove the tank and before you touch anything underneath, look at where the spark leads sit on the head. Mine had rubbed through and when wet would lower the resistance just enough to divert the spark of one cylinder to the head = minor but noticeable loss in power.

    I just attacked mine with duct tape after that.

    Good luck.

    Edit: when I say rubbed through, it had rubbed, not right through, piss all was actually taken off the spark lead insulation itself.
  4. thanks for the replies

    that clutch basket may be the problem. My bike is alot louder at idle than it used to be (when i take my hand off the clutch) ANd it makes those knocking sounds that the article talks about.