Cheaper spark plugs

[jchesshyre]

Anyone used these or know if they could be used?

https://www.opieoils.co.uk/p-63965-ngk- ... trode.aspx

I find I have to change the DPR9EIX-9 ones after about 8000 miles anyway, despite claims that they last way longer than this, so seems a waste of money when they're getting on for £10 each.

And any ideas why Honda specified the platinum ones they did rather than just standard plugs?

[Dickiebig]

You might just have to be your own guinea pig on this one. You would soon see if the initial performance is ok, any drop off in actual performance or fuel economy should be noticeable. I think the vast majority of people with stick with "standard" as in reality there mileages are low enough that the cost is not a driver. Perhsps MacV2 would be a better person to comment as he puts serious mileage on his comuter storm

[MacV2]

You might just have to be your own guinea pig on this one. You would soon see if the initial performance is ok, any drop off in actual performance or fuel economy should be noticeable. I think the vast majority of people with stick with "standard" as in reality there mileages are low enough that the cost is not a driver. Perhsps MacV2 would be a better person to comment as he puts serious mileage on his comuter storm

Yeah, I just stick the correct ones in...Despite the Scotish sounding name I'm not a tight butt...

[Dickiebig]

I'm not a tight butt...
[/quote]

No no no no

[jchesshyre]

LOL Mac. But, I want to know why the correct ones are correct...why did it need platinum (and now iridium) ones?

[8541Hawk]

https://www.championautoparts.com/Parts ... rials.html

This gives the basics though you need to remember that these bike use a WSS or wasted spark system. Which means the plug fires everytime the piston reaches TDC (well technically how ever many degrees before TDC the ignitions system is set for) which can be hard on plug and can be very sensitive to plug type.

So while you can run standard "copper" plugs, you my find that you could need to replace them at very short intervals making them actually more expensive to run.

[jchesshyre]

Interesting link, thanks. They say iridiums can last for 100,000 miles (though in a car I imagine) and also the service interval for the FI Varadero, which had iridiums as standard, is inspect at 16,000, replace at 32,000, yet I can feel a difference when I change them at 8000!!

My '97 CB500 also has a wasted spark ignition system yet has standard plugs specified as standard (which I use with no issues)...

So I'm still intrigued as to why platinums were specced by Honda. I wonder if it's because they run a bit hotter (according to that article) and so are better at burning off deposits from the perhaps not always complete combustion that we have with these carbs?

Think I'll try a pair and see how throttle response, starting, fuel economy are after 4 to 8000 miles.

[tony.mon]

With iridium's you can't re gap, but there's much less centre electrode wear, so you get longer between service intervals.
Using standard plugs should be ok, bug check the gap every so often.