Mis firing help Please.

Ammoman · Nitrous Nuisance Joined: 04 Nov 2012 Karma :

The wife's 2012 Yamaha Fazer8 has been unused for 9 months in the Garage. Apart from starting it every couple of months it ain't moved.
It now Mis fires and splutters when below 2.5k revs, over that it runs perfect. Fresh fuel and a 40 mile blast and still the same. Question

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2013 ZZR1400 & Honda CG125 1986..

MCN · Super Spammer Joined: 22 Jul 2015 Karma :

HT.

Coils/Coil, Lead/Leads.

Maybe not enough current at low RPM to drive the ignition.

Battery leads and battery condition too.

9 mths damp exposure. if carbon leads the moistuere creeps in.

Try skooting a load of WD-Fuckwit over all the HT system.
If you have a place to run it in dark
kness you may even see the HT current tracking to earth.
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Disclaimer: The comments above may be predicted text and not necessarily the opinion of MCN.

Robby · Dirty Old Man Joined: 16 May 2002 Karma :

40 miles should clear out the fuel system. See if it is still misbehaving tomorrow, after everything has had a chance to soak away in fresh fuel.

Otherwise as said, electrical. Spray anything that looks electrical with WD40, and put the battery on charge overnight.

I would also hunt down and check the main earth strap from the battery to the frame, seeing as it should be fairly accessible. If there is any rust at either end, clean it up with some emery paper and give it a smear of vaseline.