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Losing Top End Power

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by nodz, May 3, 2005.

  1. I appear to be losing top end power on my bike.
    Admittedly not much top end anyway beng a CB250...:LOL:
    However, went on the organised ride on May 1st to Yarra Junction.
    At a couple of points bike was struggling to maintain 80kmph when wound out to throttle stops.
    I changed the spark plugs prior to this ride (exactly the same replacement) and thought this could be the problem but the bike was not misfiring at any point.
    When we got up to the top of the hill at Neerim Junction and started to go back down the other side, the bike would not speed up. I backed off the trottle and then wound it out again but still no improvement.
    Bike is due for 24000km service, so I will take it in as soon as I am able.

    Anyone got any ideas in the meantime?

  2. Nodz, thought comes to mind that it may be fuel related. I think the CB's use a single carbie with a manifold that feeds both cyclinders. It could be the carbie needs a going over. Of course it could be many things but that is one that sticks out in my mind. Could be float level, or main jet etc

  3. Taking a wild stab here nods...could the air filter could be blocked?? :wink:
  4. could be water in the fuel/carbuerretors

    i had the same problem on my old bike. no power at all, even with full throttle . there might be water in the carbies. bleed them inot a container, the fuel should be blue (i think) if u use regular (pink if premium) and u should see the water floating on top.
  5. have you checked that your throttle cable is proberly adjusted?
  6. Common words - "could be.........." :D I really wouldn't know what it "could be" since it "could be" anything. But when I said the similar thing to my mechanic "It seems that it is loosing power slowly" he goes "you're just getting used to it mate" And he is bloody right!!!!!

    Anyway, hope you get it sorted out real quick and cheap nodz so we can stroll around again. But true it is, caribies and vacuum hoses are biatch to fault find!

    If you were giving your bike a lot of hard work on that day, it might be temparature related as well. I had one vacuum hose leaking after intake manifold joint gets hot. Pissy little thing but it took me ages to find it!!!
  7. I agree with that! although (oddly enough) my bike has been feeling faster lately :p maybe it's trying to impress me coz i'm thinking of selling it
  8. Try some of this -> cleaner

    Apparently it does what is says on the tin ;)
  9. Sounds like fuel starvation (carbs/ fuel filter/ gunk in the fuel line).
    Could also be crap in the tank.
  10. buy a kawasaki they dont give it up lol