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    • #9575
      Steffan rees
      Participant

      Hi I just bought a  hyosung comet 125 2010 only done 4000 miles  I took it down the road it ride well for abit when going fast  around 50 mph it just no power  at full throttle if I let off on the throttle It goes again any idea what’s wrong with it? Thanks

    • #9578
      HyoSteve
      Participant

      Try new spark plugs 1st.

    • #9579
      Steffan rees
      Participant

      I have checked the park plus they have good spark

    • #9593
      ♠️ M77
      Keymaster

      Have a look at the spark plugs ,  because they may spark but what if they spark yellow  (meaning its time to change it or the electrical system is weakening = eg. Coils & Caps as a married pair)
      A bad cap makes a bad coil or vise versa that’s why we change them out anyways to better one. (can’t go wrong with NGK’s)

      If it has IX Iridiums  ,  put them to the side and try “NEW” stock CR8E and go for a ride or LASER Plugs (like these)
      The Hyosung 125cc twins don’t really like the “Blue Box IX Iridiums” that’s why henceforth.

      If woes continue, take a picture of your plugs so we can see how dark your threads are and what colour is the center.

      If we can sort the “Plugs , Coils,  Caps, ”  first , it becomes a lot easier to diagonose fuel system next   (if she is still in a mood)

      Worst case senario ?  =  Compression Low  or Valves Too Tight  (can’t escape this , as it will need doing for all hyosungs , if the last owner did not do it)

      Best case scenario ? =  Carb gets an ultra sonic clean  (no rattle cans) , has to be ultrasonic and or air compressor in the entire carb body as it has many holes,   change the ORINGS under the rubber intake pipes  (they cake with age, so we replace em , like these ones …)   and don’t play with mixtures ,  but do make sure float height is 7mm  (see this link and look for a picture of float height)   <– That thread is also a good read too 🙂

    • #9601
      Steffan rees
      Participant

      Okay thank you for the help I have ordered spark plugs and intake pipes and new fuel pipes and filter as it’s still got old ones on it and vacuum pipes I’ll let you know how I get on.

    • #9604
      ♠️ M77
      Keymaster

      Okay thank you for the help I have ordered spark plugs and intake pipes and new fuel pipes and filter as it’s still got old ones on it and vacuum pipes I’ll let you know how I get on.

      new Intake rubber pipes or just the O-Rings ?

      If your inlet-manifold pipes have split, send some pics and ill advise if its okay for you to send em to us (then myself & my cnc man will see how best we can save them/fix them) ,  they are very very valuable things now these rubber parts!
      So much so even MotoGB UK sells them for £140 each (the real Hyo UK,  not the FakeSpares website). Other places in Europe charge £110-200 a piece, plus there is the taxation rape to import them lol

      Look after them 🙂

    • #9605
      Steffan rees
      Participant

      I have ordered new intake pikes just in case gunna strip the bike when parts get here to have a proper look into them and I’ll let you know if the damaged or if there okay just handy to have spare parts on two engine in bits as well and carbs

    • #9606
      Steffan rees
      Participant

      I meant pipes auto correct 😂

    • #9611
      ♠️ M77
      Keymaster

      Whatever you do, don’t bin anything , if it can’t be fixed,  send to us up north and we will deal with it!

      Gotta to save these big beauties now,  not many left on road 🙁

    • #9615
      Steffan rees
      Participant

      Will do thank you

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