Iridium Spark Plug Life

[Rob]

Changed plugs at 12K miles as recommended. Also changed from Platinum to Iridium as Honda recommended.

Definite improvement - just new plugs or Iridium?

Now approaching 24K so have bought a new set to change as part of the service.

Would you change them? I have the plugs, cost £11ish so not expensive, but Iridium ones are supposed to last longer?

Slightly off topic - I've read that Iridium has a smaller tip so gives a more powerful spark which gives a more 'complete' burn of the fuel/air mixture. Sounds like baldrocks to me - a better spark maybe, but once the mixture has ignited then surely it will all go bang just the same??

Then again a lot of car manufacturers use twin-spark. Can't see why they would have the added expense for no gain unless it's marketing crap?

Maybe a bigger spark gives a bigger initial bang so helps timing? Too late and too many beers to think clearly but I'm sure some bright spark (see what I did there?) will put me right

[VTRDark]

a better spark maybe, but once the mixture has ignited then surely it will all go bang just the same??

I think you have answered your own question there. Once the mixture is ignited.

Think of a lighter and flint. You can flick the wheel on a lighter and sometimes there is not a clean enough spark to ignite the gas. So you flick it again and there is a cleaner bigger spark and the lighter has a flame. Just a thought!

Here's one of Mr Mons write ups on Iridium plugs http://www.vtr1000.org/phpBB3/viewtopic ... dium+plugs



(:-})

[Rob]

is Mr.Mon really suggesting changing Iridium plugs every 5K?

Did a bit of searching and NGK seem to suggest 20-30K for bikes for the Iridium IX range (Depending on application)

Maybe I'll just stick to 12K that Honda thought was fine for Platinum. As it's used for commuting and as a runaround my bike has a very easy life but does a fair few miles so don't want to be changing things too often. Then again if it affects MPG it might be money well spent

[seb421]

is Mr.Mon really suggesting changing Iridium plugs every 5K?

Did a bit of searching and NGK seem to suggest 20-30K for bikes for the Iridium IX range (Depending on application)

Maybe I'll just stick to 12K that Honda thought was fine for Platinum. As it's used for commuting and as a runaround my bike has a very easy life but does a fair few miles so don't want to be changing things too often. Then again if it affects MPG it might be money well spent

They ain't that expensive mate if you get them online, I do mine every 2 - 3k with an oil and filter change

Sent from the Bat Cave via Cup and String

[snakebitey]

Just got mine for £6 a plug on eBay, and a previous set lasted me around 10k on the CBR before it started lurching about.

I'd change them now if I were you!

The science is there for iridium plugs - the fuel's only got a split-second per cycle to ignite, and the stronger the spark the quicker it ignites, and the more force the explosion will have = more power! And therefore better fuel economy

[tony.mon]

Yes, I do.
Mainly because the gaps aren't meant to be changed, unlike normal plugs, and you can't clean them without special equipment.
At £6 a pop they're a consumable, think of them like petrol and it doesn't hurt as much.

But can you leave them in for 15,000 and still run the bike as normal?
Absolutely.

But when you change them at 5K you don't notice a difference in performance, meaning that they're still working as efficiently as they were when fitted.
When you change them after 15K you notice a difference, the engine's perkier, more responsive, fuel economy's better, and this tells you that the performance of the plugs has been less than optimal for a while.

How long the while is depends on too many factors to list, but why run an engine at less that it's best performance even for a short while?

[VTRDark]

you can't clean them without special equipment.

What would one need for that? It would be a useful addition to the tool collection.

Also with the Iridium's they are not as accurate for taking plug readings. Just something to be aware of.

(:-})

[tony.mon]

http://www.globaldenso.com/en/products/ ... qa_23.html

The little sandblaster boxes work ok, but as Denso say, use low pressure if connected to an air reservoir.

I've seen one that work by electrostatic means, but can't find it in t'internet at the moment.

[benny hedges]

I do mine every 2 - 3k with an oil and filter change

fook dat id be changing oil every mth lol!