Question about 1991 Honda ST 1100 Pan European

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Flat spot /backfire

2002 ST1100. 43000 miles.back fired a few times when decelerating and has now developed a flat spot an first opening of throttle. over 2000rpm is normal

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  • Andrew Harman Jan 20, 2009

    I have a 2000 ST1100Y and I get a small misfire when cruising for about 5 minutes at about 2500 rpm in 5th gear on the open road, I have cleaned the carbs, replaced all the plugs and HT leads but still it is there, even the local Honda dealer is not sure what it could be all they can suggest is for them to replace half the electrices in the hope it finds the problem but i done have a bottomless pit of money, Any other Idea's !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


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Hi and welcome to FixYa,

Initially, pls check the airbox, air cleaner and how the assembly is fitted. Backfire on deceleration indicates lean mixture (too much air, too little fuel). A flatspot could be anything, let's try the air cleaner/box first and proceed from there. Might get lucky to solve both problems with 1 solution.

A favor, I would rather that you please do not rate this solution (yet) not unless it solves the problem. Due to my current rank and rating, even a Helpful would be detrimental to my standing.

Good luck and Thank you for using FixYa. Happy Holidays.

Posted on Dec 18, 2008

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