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I have a 2005 R1 5VY that has done 27,000 miles and was used on the track about 10 times. I decided to check the valve clearances last week and they were all in the approved range.
When I put everythng back together and started up it only ran on three cylinders. I had put new plugs in - Iridium and not the twin spark ones that I replaced. I cannot tell by looking at the new plugs which cylinder is not firing. I am fairly sure that I have put the leads back on the right plugs.

How can I test the ignition coils?
Rod

Not exactly a newbie post bud , this post is more for the 5vy section !

Welcome in anyway
If I remember correctly ( getting old & Alzheimer's doesn't help :p ) the 5vy's had individual coils on the ends of each lead ? Some times on the older models the ends of the leads deteriorate and the wire running through them breaks , unscrew the coil & check the lead ends , if knackered cutting 10mm usually sorts it but make sure they're long enough , as said that's on the older models , worth checking though .

You are correct mate.
Do you know which one isnt firing ?. Unclip each coil and try on another plug. The wires into the back of coil are very then and you might have tugged one out on install. Not much room on there as you already know

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Welcome in mate