A couple of weeks ago on two the bike had bit of trouble starting for the second time.
There power from the battery but it wouldnt catch…after some percistant pressing of the starter it came to life.
I think its the sparkplugs as ive repleced them 14k ago (iridium ones). So i ordered some.
Well since ive placed the order the bike has been fine and starts straight away…
So do i replace them? Could it have been somethig else.is 14k long enough and even tho they mightnot need it i should replace them anyway?
Can’t hurt to put new plugs in seeing as you’ve bought them…
Crikey this is exactly the same dilemma I’m in - sometimes it (my old Hornet) starts, other times it has trouble catching - it never used to be like this - the other day I was a few miles from home and it didn’t catch and the battery was a bit low because it had not been used for a few weeks and the starter being on for longer than usual meant it started running out of battery juice so I had to bump start it to get it going again.
Honda have strangely long service schedules on things like plugs - e.g. they say change em every 16,000 miles -whereas on other bikes it is usually half that - the plugs have been in the hornet for about 14k like yours Pan - mainly because I have been slack on maintenance recently - in the past I ignored the Honda schedule and changed them every 6 to 8k.
I haven’t ruled out a load of other things for it not catching - but in view of the fact that the plugs have been in there so long my first solution will be to change the plugs.
Hopefully this will improve the starting situation.
Spark plugs …
Swap em out every 12,000 miles, cheap as chips they are too 
funny thing is that it hasnt done it since… i wonder if it could be something else.
might go ahead and replace them anw tho you guys are right… no harm.
I wonder how many perfectly good spark plugs get thrown away each year? Is there anyone left that still cleans them?
A friend who runs an independent service garage always changes them on big services as it’s just not economic for the customer to have him spend half an hour cleaning the old ones. But if it’s a DIY job, why not?
Oh. My experience has been that you may get better starting after changing the plugs but that’s perhaps due to lower resistance from clean plugs (?) but that’s also treating the symptom rather than the real cause. Commonly a battery that’s only apparently good which is quite capable or turning the motor or giving a nice spark but not both at once.
Oldschool, Oldguy …
40,000+ miles between plug changes on the old Norton and Triumph, it was the points that wouldn’t last the pace, fitted both with Boyer ignition and sparking issues sorted.
The magic wipes of wire brush and emery paper a forgotten art 
Yeah - I agree with the two posts above - it seems really wasteful from a moral point of view just in terms of natural resources to throw a dirty but still perfectly good plug in the bin.
I’m gonna be cleaning mine from now on while maintaining a log of how many miles they’ve been in there.
What’s the best way to clean them?
Tell me if I’m wrong, but on a modern bike do you really need to be cleaning them at all?
Engines should be buring fuel cleanly enough so that you only need to watch out for erosion of the conductor thingy and maybe resetting the gap.
Saying that, arent iridium plugs meant to be good for far more miles than standard ones?
http://www.spark-plugs.co.uk/pages/technical/diagnosis.htm
Art “Old school” it may be, but that’s my point. Why? You are talking of 40,000 miles from (a guess?) old type plugs, and why not?
I just have a sneaky feeling we are all being suckered into throwing perfectly good spark plugs away for no particular reason.
Duncmac The received “wisdom” is that iridium plugs are supposed to last longer than standard plugs. So, if standard plugs can last 40,000 miles, an iridium plug should last most of the life of a modern motorcycle.
