Dumb Question

[Guest Thundering Subash]

Should you replace them every 6,000 miles as the maintenance schedule recommends? This seems a bit often to me. I only have to replace them on my Chevy Truck every 100,000 miles (so far so good at 85,000-I hope they're not seized in there for good).

 

It's not the price, as they're cheap plugs, it just seems like a short interval for spark plug replacement.

 

-Chris

 

[al_roethlisberger]

Get yourself some of the newer iridium plugs from NGK or Denso, and they'll probably last the life of the bike, or thereabouts.....

 

al

[TX REDNECK (R.I.P.)]

Don't buy those Iridium plugs, it could cause the world economy to falter

[al_roethlisberger]

Don't buy those Iridium plugs, it could cause the world economy to falter

 

 

Bwahhh Haaa Haaa... yessssssssss

 

(...and other evil megalomaniacal laughter inserted here)

[Motomonster]

Al, o' performance guru:

 

Is there any performance advantage to the iridium plugs?

[al_roethlisberger]

Al, o' performance guru:

 

Is there any performance advantage to the iridium plugs?

 

 

 

... oh sure, probably 10hp per plug

 

 

Like most things, I doubt it. I have "heard" that they do give a better spark due to reduced resistance, and are more durable, yadda yadda yadda

 

 

When I was having various issues last year, a very reputable shop(Hare Racing) said they had luck with the iridium plugs cleaning up some rough running bikes, and seemed to last a long time. So I thought, what's the harm since I needed one step cooler(if I recall) plugs for the dual-plug conversion anyway.

 

I have no idea if in fact they made any real difference though, as other variables were in play at that time affecting the bike's not idling, etc...

 

I have them in the bike, and YMMV...

 

al

[twhitaker]

I once put 36,000 miles one set of NGK plugs. They looked to be still in good shape. Smear a little bit of antisieze paste on the threads unless you want to find a use for a "Time-sert."

[Guest rrbasso]

I replace Plugs at every 10000 service.

[roberto]

Awwwww, come on...

 

Change the plugs - they will deteriorate - and do it at the normal service intervals. The condition of the old plugs will give a good indication of any potential problems.

 

Older guzzis require oil, filter and plug change every 1500 miles!

 

I had an old Honda CB750 that would kill the plugs within 1000 miles - on inspection there was never anything visually wrong with them - they just wouldn't work any more.

 

Go on, change the plugs. It's one less thing to worry about.

[pete roper]

The reason plugs used to crap out early was due mainly to fouling, mainly caused by lead in the fuel. Since lead is no longer added plug intervals are greatly extended. The fact that many motor cars now go 100,000Km between plug changes is indicative of this, the environment inside a combustion chamber is not that much different be it in a car or an older style, air-cooled bike motor. It is possible that the average bike motor will be used harder than the average car motor but this in itself won't make that much difference to the life the plug leads.

 

By all means change plugs regularly, but it is unlikely that running a slightly older plug will make ay noticeable difference unless the old plug was faulty to start off with. In my experience playing around with the gap and ensuring that you have the right heat range is far more beneficial than simply sticking in new plugs. If you find a marked difference between performance with plus of duiffernet types it is most likely down to subtle differneces in heat range more than anything else and I'm afraid all the magic plugs are simply snake oil. Even the multi electrode/surface discharge types will, in the environment of the combustion chamber, rarely, if ever discharge through more than one route, ie, you get one spark!

 

Pete