Do I have to take up stock in NGK?

First off, my 426 since I have it jetted correctly starts first or second kick everytime cold or hot...

I recently went to change out my Magura hydo line for a ASV lever/cable assembly...had to take off the tank to feed the Magura through and the tank sat off the bike for about a week before I could install the lever and cable. Once I got it all back together...the bike started like usual, and then died as soon as I touched the throttle...then it wouldn't start.

I went through and checked everything...

-took off filter in fuel line

-valves (exhaust was tight but still in specs)

-inspected and cleaned jets

-tried with different fuel screw settings

-inspected spark plug...good color and had spark

When I put it all back together it still wouldn't start...so I threw in a new spark plug and *poof* started first kick!

This is the 2nd spark plug in 6 months since I have owned it...is that normal, or are these thing that delicate?

I can't imagine a plug going bad for no reason. I would put the plug, that you took out, back in and see if you have trouble with it again. If it works fine, then your problem lies elsewhere. You may have a faulty electrical connection somewhere in the harness under the tank. When you routed the line for the magura, you might have caused a connection to loosen. Maybe a wire's insulation has worn through and it moved enough to ground out the electricals. You may want to check the connection between the plug wire to spark plug (loose or corroded) or the plug wire to coil. Even a killswitch going bad could be the problem. How old is your fuel line? Could be that the inside has started to come apart and caused a blockage. Just a few ideas to look at since, other than becoming fouled, plugs are pretty much reliable, at least on thumpers. Hope one of these ideas helps!:prof:

6 month plug life isn't altogether unusual for a 426. The ignition isn't as strong as it could be at cranking speed, and they can be fussy about plugs because of it. This is especially true if you are in the habit of starting your bike once in a while just to hear it run, and not letting it warm completely up. When this is done, the plug never gets hot enough to clear the fouling deposits off of it.

This is especially true if you are in the habit of starting your bike once in a while just to hear it run, and not letting it warm completely up. When this is done, the plug never gets hot enough to clear the fouling deposits off of it.

This could be it Gray...I did start it up to warm up the chain for re-lubing when the magura broke on me. Later that night after thinking about it I went out and started it again to make sure something in the engine didn't lock up at the same time the clutch broke. :prof: Either time never got more than 1 minute of run time before I shut it down.

mine does that on occasion, plug has spark but still wonr start, i either pull it out and sand it a bit, and that usually works or just throw a new one in.

I know it is not a Yamaha but my Buell lightning runs like crap if I don't let it warm up every time I ride it. Pull the plugs and they are fouled. Clean them and let it get hot every time before running and she runs perfect.

Just underlining the point that some bikes will foul the plugs if they are not warmed up properly..

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