Proper spark plug gap & Iridium?

[eakins]

New 2010 Yager owner here w/ only 800 miles. Loving it so far.
The manual I have says .9mm, but the sticker on the battery access panel says .6-7mm.

What is correct? The oem NGK in there was gapped to .8mm (it has only 800 miles on it)
The -9 is suppose to be .9mm and that agrees with the manual, but conflicts with the sticker.

I also tried a Autolite XS4164 Iridium (suppose to be a DRP6ea-9 cross) but the engine runs worse with it.
Idles rougher, but does rev out just fine.
Wondering if adjusting the Autolite to spec will help or are those not good in this motor?

I run Iridium (NGK or Denso) in every other motor I own and I so am a true fan.
There is no DPR6EIX-9 but there is a 7 (colder plug). Denso has nothing in the 6 range.
Local parts guy said NGK use to sell a 6 Iridium in this size but stopped for some reason.
Anyone use a DPR7EIX-9 successfully or do I just stick with the oem copper NGK?

Yager200i says use a Pulstar HE1HT9 spark plug. How about those? They are new to me.

Thanks, Bill

[eakins]

Is the connector near the battery a factory computer/diag connection? Are there any factory updates to the ecu?

[eakins]

Anyone on the proper gap?

[CROSSBOLT]

Use the sticker. Kymco manuals are filled with errors and conflicting information.

Karl

[eakins]

I did figure the sticker was correct.
I actually bought a dpr7eix-9 Iridium after reading yager200i maintenance thread. Left the gap at .8mm how it came in the box however. Runs great. Should I pull & decrease to .7mm? Changed the oil & rear fluid too. Will switch over to synthetic engine oil soon. When is it considered broken in?

[eakins]

been running that 7EIX at the gap it came with the past and the scoot is running like a champ!
starts fasts and idles well.

noticed with the factory copper plug when i pin it from start the rpm went to 8k and accelerated.
when I changed to this plug it only goes to 7k but then will hit 8K+ at speed.
this normal?

[KymcoRockr]

Try the Nippon Denso. It's a much better plug. They invented the Iridium plug and the electrode is smaller than the NGK.
Who still gaps plugs? They are fine right out of the box.

[eakins]

Try the Nippon Denso. It's a much better plug. They invented the Iridium plug and the electrode is smaller than the NGK.
Who still gaps plugs? They are fine right out of the box.

I've used the Denso Iridium many times in the past but on my Mp3 400 for some reason the NGK Iridium idled alot better than the Denso Iridium so I stuck with NGK this time. The Denso does has the patterned smaller .4mm end while everyone else had to go up to .6mm.

As for gapping yes they do come pre gapped but it's a universal plug in a world of specific machines.
I kept the gap the same from the box, but it is indeed out of spec from what Kymco has labled.
I figured since the spark is easier to jump on the Iridium, a .1mm additional wider gap will be ok.

[Stig / Major Tom]

I too had better experience with the NGK.
Stig

[Yager200i]

I'm running a Pulstar HE1HT9 spark plug. It fixed my rough cold idle and gives a bit more grunt at low engine speed, which I needed, since I've modded the clutch to engage at 2500 RPM.

In doing research on spark plugs, I found the Iridium plugs don't work as well for waste-spark systems like ours. In fact, any spark plug which has a tiny point won't work as well with a waste-spark system... a sharp point makes it easier for the charge to jump the gap, but the waste spark has to jump from the flat center post to that sharp point, which is harder to do, so it's unbalanced, which somehow makes for a weaker spark since the voltage of the waste spark isn't completely drained by the time the forward-spark is next initiated... that's likely why FrankenYager didn't like the Iridium plug as much as it likes the Pulstar.