Author Topic: Iridium spark plug - Experience?  (Read 753 times)

Offline owain

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Iridium spark plug - Experience?
« on: 06.09. 2017 20:15 »
Righto, I've just bought a pair of standard Champion N3C spark plugs for a Triumph Trophy and thought about maybe 'upgrading' my A10 plunger to some iridium spark plugs. From what I understand and from the videos I've seen on youtube, they appear to provide a superior spark than standard plugs.

I should say that there is no problem with the NGK B7HS plugs that are fitted at the moment, but if I can fit a superior spark plug in there that will spark better/easier then why not? Any experiences with Iridium sparks?

The sparks I'm thinking of getting are Denso IWF22 spark plugs. Non-resistor type like the iridium NGK's ;)
Sweden & North Wales
'50 BSA A10
'69 BSA A75R
'29 Rudge Special

Online Triton Thrasher

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Re: Iridium spark plug - Experience?
« Reply #1 on: 06.09. 2017 20:32 »
They have lower voltage requirement for the same gap and probably resist fouling better.  You may not notice these differences at all, though.

They will last longer in an engine before becoming eroded though.

Online JulianS

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Re: Iridium spark plug - Experience?
« Reply #2 on: 06.09. 2017 21:04 »
I used Denso IW22 Iridium power on my A10SR for a number of years. It ran better and cleaner but plug life was low and at about £9 each expensive. I swopped to Denso W22ES-U which last much longer. Never cared for NGK.

I presume the irdium plugs did not like my magneto.

All the Iridium power plugs are resistor types and I know people say dont use resistors with magnetos but I have never had a problem. BSA of course, fitted our A7 and A10 with resistor plug caps.

Offline mikeb

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Re: Iridium spark plug - Experience?
« Reply #3 on: 07.09. 2017 04:32 »
when my b33 had a weak mag (condenser problem) i fitted an ngk irridium and i got a little better warm starting and running. eventually i still had to fix the mag (currently on bench)

but for my a10 it would be a solution without a problem.

if you do get one make sure no resistors built in... most of them have
New Zealand
'61 Super Rocket  - '47 B33 -  '21 Triumph Speed Triple RS