Forum

[albert]

Gazebo I did notice when changing the plug on my CGT 535 that both the original plug and cap were both resistor type as fitted from new.

[Biscuit Barrel]

NGK, Champion and ND recommend no anti seize compound is applied on plug threads. http://www.ngksparkplugs.com/about-ngk/ ... park-plugs apart from galvanic corrosion from copper grease on aluminium (cyl heads) and the fact the plug has to earth through the threads there is the point of over tightening. Having said that after 60k or 100k miles there is going to be very little lubricant on the threads. In fact none. I use NGK iridium plugs on all my bikes as a fit and forget, but even on my very modern efi 1050 Sprint harder cold starting is noticeable vs copper plugs. I do fit them dry as they'll be in the engine long after the engines are knackered. My Harley dealer fills the plug cap with dielectric grease before connecting to the plugs which is probably a good idea. Harley plug caps are very soft silicone and do seize on the plugs but the grease makes them easy to remove as well as keeping water out.

[Off to the shed again]

Strange. I have in front of me Champion Aviation Service Manual, V6-R. Page 11, Installation procedure of their spark plugs says to apply anti seize compound carefully to the firing end thread. This is also in the Aircraft Maintenance Manual and Lycoming Maintenance Manual. REgards, Chris.

[Presto]

It is incorrect to assume that a resistor plug especially an iridium plug must be used with non-resistor plug cap. This is contrary to NGK’s own advice.

The nominal loss of current when using a resistor cap and plug – about 10% - is more than offset by the efficiency of the iridium plug.


PS In my experience an iridium plug does help starting. I’d not use any other.

QUOTE FROM NGK website


All motorcycle manufacturers now comply with current legislation which demands a standard of noise suppression on every vehicle. This is achieved usually by fitting NGK resistor covers though in many cases a combination of NGK resistor covers and NGK resistor spark plugs (R type) is necessary to satisfy the ministry tests. It is emphasized that despite the use of both resistor covers and spark plugs in such engines, due to the unique and superior construction of NGK products there is no loss of performance or shortening of service life.

[ric]

Ironically because of the requirement of modern systems and their need to have the correct amount of suppression, NGK only guarantee that their iridium plugs (recommended for use in such applications) actually come fitted with 5kilo Ohm of suppression.
All their other plugs from the less than premium ranges vary in resistance.

[Gazbo]

Well - I bit the Bullet (No pun intended.)
Bought a champion WCX600 180 cap. ( 10KOhm). Coz they look right !
so I will have 15 kOhm total with the iridium in there too.
Had a look on some close ups on line. it doesn't appear to have the screwdriver slots for stripping to remove the resistor, so......
You know the best weather forecast - is to look out of the window ?
Well - I'm going to try it anyway. suck it n' see.
I'll eyeball the existing spark, and visually compare it to the new setup, with the plugs out of their nest, before proceeding.
As long as I'm not going to ruin any of the ignition components, I'm not over worried.
(Can always revert if it's a duff setup anyway !)
cap not yet arrived. I have a rubber booit (As they say in sunny Yorkshire) to fit betwixed cap and lead, to keep the wet stuff out.
Also bought some dielectric gloop for inside the cap.
if she runs ok I'll try the bucket o water test.(At the weekend - when she's not in demand !
If all is well - I'll report back here.

[John L]

All this, just to fit an iridium plug (which won't help cold starting, and which the bike certainly doesn't need ??
The mind boggles.......... (Sorry, just my jaded view....)

[Presto]

Different experiences here on iridium plugs. I have found that they definitely help starting - in 2 strokes and 4 strokes. I have used NGK and Denso iridium and would always fit them. They are cheap enough. Technically and in use they are in my view a far better product.

[Gazbo]

John L.
I never intended to bang on forever about it, it's more of an experiment than anything.
My bike is always 3 or 4 presses of the start button, before she fires. (Fine once running)
I bought an iridium after reading Hitchcocks bit.
Unfortunately - the horrible tin cap won't fit, as the nut is not removeable, so needed another cap (which I wanted to change anyway. Sorry if it gauls you, just asking for advice - thats all.

[John L]

Pay me no mind, Gazbo. It's your bike and you do what you like to it.........