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help again! droning engine

Discussion in 'Technical and Troubleshooting Torque' started by idontlikemondays, Sep 22, 2006.

  1. well my engine has had a droning noise since i put on a staintune exhaust. when i say droning, the engine when at cruising revs, at about 45-50 in 4th and at about 60-65 in 5th, ironcially this is where the bike sits on most happily on a lazy throttle, the noise a constant frequency, but a changing pitch. it stops if i give it any more throttle, or release the throttle. i checked other threads on the topic, which all seemed to say change the plugs. did that, nothing. took it in for its major service, again no change. its more noticable when i have the bung in the exhaust, when i can actually hear the engine. im starting to think its just something you dont notice with the factory baffle. but im also worried its a loss in back pressure, maybe resulting in engine damage. when i got the new exhaust fitted, i didnt get it rejetted on advice by the honda dealership. its got just over 24000ks on it. any help to put my mind to rest, or my hands to work to fix it would be greatly appreciated.

  2. All perfectly normal , what your hearing is all the bikes 'harmonics' working together.

    Personally I love it when I hear the "thrum thrum" of a well tuned machine running just the way god made it. :cool:
    The bigger the engine the better that sound / feeling is , try sitting in the cab of a 650hp truck when the harmonics all get in sinc! gives me a woody every time !

    :LOL: :LOL: :LOL: :LOL: :LOL: :LOL:
  3. I doubt a drop in back pressure for a 4 stoke would actualy hurt any parts, though yes, tuneing could be very affected. Stick the bike on a dyno if your that worried and let them sort it out.
  4. its good to know its all normal. thanks!
  5. Didnt rejet it :shock: well ok its a 250 and performance might not change that much but hey i always thought the best thing to do when you change exauhst would be stick it on a dyno and have it jetted to suit, but hey thats just me :grin: