Tuning and modding » Spark plug gap

If this has been cover somewhere else on the forum, I couldn't find it. I'm getting ready to do 12,000 mile maintenance. I figured if I was going to go to the bother of pulling the plugs to inspect them, I'd just replace them. They don't cost that much, after all. I didn't see anything in the BMW maintenance manual about setting the gap. I've also never seen a plug like this. Looks to me like it would fire in two directions, not across one gap like a traditional plug. I've also never had to adjust a gap on a new plug for any of my Hondas unless I were clumsy and dropped it. So, do you have to set the gap somehow or are they pretty much good to go, pop 'em in and torque them?

Thanks,

Just screw the new ones in.

Copied from my RS manual

Spark plugs, manufacturer and designation NGK LMAR8D-J
Electrode gap of spark plug 0.8±0.1 mm, when new
1.0 mm, Wear limit

Page 182 0f uk/europe version - rtfm to confirm!

I see it now in the US manual, page 179. 0.03" +/-0.01". I went straight to the repair manual CD thinking it would be covered in the section on replacing the plugs. Thank you for pointing me to the place I should have looked first. I feel silly now.

Ignore this comment as I deleted it on re-reading the OP :)

Glad you found your own answer as I did have concerns my advice would be wrong due to different fuel used across world markets. Different octanes, unleaded, e 5 and e 10 etc.

My dad bought a set of surface-gap Fire Injector spark plugs (probably from an ad in the back of Popular Science magazine) during the early 1960's and installed them in his 1957 Ford sedan. They worked, but I doubt they worked any better than the original single electrode spark plugs. Royal Enfield uses Indian-made Bosch two electrode spark plugs in their 500 single bikes and they really suck. Almost everyone switches to single electrode NGK plugs to keep their Bullets running smoothly - well as smoothly as a Bullet will run.