Experiences - Comparison "new" Rotax spark plugs vs NGK

Sooo... Brand new 582 mod 17 with (obvs) new Rotax plugs. Whilst checking and adjusting for burn at 12 hours - massive mag drop! (The burn was ok!) Yep, after troubleshooting it was the (a) plug/s! I've been told they easily crack the ceramic whilst taking them out and in!  4 new warranty plugs later and its good. I ain't touching 'em now! I've not looked up the NGK equivalent 12mm plug. Can someone please enlighten me, please!

Dear David Alan,

which kind of Rotax spark plugs where installed at your 582 Engine? Are they branded with Rotax? I know the Rotax spark plugs which indroduced in  SI-912 i-013 / SI-912-027 / SI-914-028 for the 912 Series. Its the part No. 297656. Are there new Rotax spark plugs for the 582? If Yes have they the same part no.?

For Your Information: The Rotax spark plugs 297656 are produced by Bosch. Similar spark plugs from Bosch are made in Russia.

My informations are: NGK BR8ES (with resistor) or B8ES (without resistor) fits for the 582. Maybe this depends on the spark plug connectors which type (resistor or not) you need. Maybe there are specialists in the forum for the 582 - sorry not my field.

I an another forum a user told that the ROTAX spark plugs (297656) had unstable qualities - maybe this was a problem in the past.

A last word for ISO 9001: I was quality manager (also R&D) for 25 Years in a big company. ISO 9001 dont mean that this cerfified company produce quality products - this is a story for old woman. ISO 9001 means you have a quality system. You manage quality - bad or worse quality also as good quality. The quality standad is not defined in the system  - only warm words but not really specified. This was specified in the interal company standards. The auditor have a look at this internal standars but he cannot measure which quality level is setted. At the ISO 9001 certification process there is no specialist who knows what a good quality is - this is only in the hand of the company. The auditor looks at the system how you handle the quality issues in your company. At bad quality products and at a company philosopie that this bad quality is enough for the costumer, the most of complains are rejected. The auditor ask how many complains are accepted and handled. This is the reason why you get goodwill replacements - never you hear that there was a mistake or bad quality.

Interesting video here from NGK

https://www.youtube.com/watch?v=53yfHLdn41k 

In summary, although NGK make multi electrode plugs for legacy fits, their view is that their time has passed and modern single point plugs of conventional design but using materials such as platinum and iridium are a better solution to the problems that multi point plugs were supposed to address, particularly longevity. They mention heat abstraction from the initial flame as a drawback of multi electrode plugs.

If you look at Champion information, the only advantage they mention for multi earth electrode plugs is longevity, because there is more there to erode.

Bosch don't appear to offer multi earth electrode plugs now except their Platinum +4 which is a bit different.

As for that scientific paper referenced earlier, it looks poor quality work to me and I can't find anything in it to support the case for the new Rotax plug. It actually says the best is no discrete earth electrode (which I guess you could regard as an infinite number of them!)

The NGK DCPR8E is a basic standard plug with a nickel electrode but was apparently up to the job. I wonder if there would be advantages in longevity using an upgrade version - DCPR8EIX for example has an iridium centre electrode.

Incidentally on the question of why the new Rotax plug has a different torque figure, I don't think it really matters. For the DCPR8E, NGK give a range of 15-20Nm as being OK, it isn't critical!

Yes, except... I can't see how plug longevity is really any issue when you can replace all eight of them at a cost of less than about five gallons of fuel.

Tyler Hathaway wrote:

Yes, except... I can't see how plug longevity is really any issue when you can replace all eight of them at a cost of less than about five gallons of fuel.

Indeed, but longevity is presented as a major advantage of the new Rotax plug. I was responding to that.

The NGK Iridium plug is about twice the price of the basic one - I don't know the life factor.

More positively, if it's longevity is a lot better, it is probably also maintaining peak performance and reliability for longer too.