Hi all i bought a xt660x 2014 last year and been plagued with problems. Kept cutting out at first so took to yamaha dealers ,they removed the kev fuel mod and checked o2 settings and told me to run on shell v power ran fine rest of the year.
Three weeks ago cut out again ,will restart but cuts out before able to ride off. Put in bike shop again they found faults on dianostics electrical issues and relays so replaced relay and tested all ok went to pick bike up and it developed another fault and was unable to rideas cut out this time showing code 43.
They've been intouch with main yamaha technical and have been told to try something to do with injection unit test other than that they agree with bike shop that ecu has a problem which is mega expensive. Any body got any idea what else to look at have already spent�400 .thanks guys help!!!

At the risk of asking the obvious did they or you change the plug because while it does show all the signs of ECU mine had similar problems and i�ve Come across others the same they have a habit of eating plugs when they feel like it.

Hi many thanks but had plug changed along with front tyre and oil when first looked at but appreciate thought.

How much are they quoting you for a new ECU?

Does the garage actually know what they're doing?

the guys at the workshop are very expierenced but cause the problem has been intermitent been difficult to trace also yamaha only let you see bog standard faults in ecu and not really excessable .

�800 plus but have found a place in powys called motomatrix that have confirmed that its the ecu so going down the route of finding a second hand ecu and having it cleared back to factory settings as i have the master re key to use and reset it to the my ignition. �120 PLUS ECU ,told not to pay more than �75 for used ecu.
Guys seemend very helpful and will also contact their contacts to help me find one.

Sounds like a plan I see no end of duff ECU�s nothing unusual.