So I bought my bike with 16k miles and am doing the 16k maint on it but I think the prev owner did all of it as the oil was good, coolant looked great (changed anyway), found out I have a K&N filter which looked brand spankin new and the plugs look like they have low miles on them (they look good), I did a gap check and they were at .021 and I know the spec is .031-.035 per the service manual. My question is how many of you guys juet threw them in your bike straight from the box w/o checking the gap? I re-gapped them the proper way as not to damage them but I wonder if this will make it run any better/start up quicker now that its set right...

 

I did change my plugs from the stock ones to the Iridium spec plug (at about 42,000km) but I must say I don't remember checking the gap before installing them. I've had these new plugs on my shelf for over a year, so I guess I was just happy to finally put them in.

 

The F4i comes stock WITH iridium plugs, orags.

I don't recall changing the gap at all on my plugs. Some friends helped me with that one, though, so I may have missed them doing it. I want to say they didn't, though.

 

I hadn't even seen those specs in the manual (general information) when I put mine in. I thought it was no more than 1mm, but that's for used plugs. The 1mm gauge wouldn't fit so they were probably pretty close to the spec 0.80 - 0.90mm (0.031 - 0.035"), maybe less. I haven't had any issues with starting/running.

 

Hmmm, well my new ones came is and the used ones I pulled out look fine so I am putting them back in, if anyone wants brand new IMR9A-9H plugs I will get them out to you for $35 shipped.

 

are the imr9c-9h and imr9a-9h the same plugs?
cause i just ordered a set of 9c-9h for my 02 f4i

 

You may want to closely compare the new ones to the ones in your bike. The "Thread Reach" might be off.
Here's a chart: NGK.

 

there is a DIFFERENCE the end tip of it is different, and the cooling of the plug and thread length and stuff like that.

 

I read something in the owners manual that says to not mess around with the gap. Don't even touch it. I'm a fan of checking the gaps though. Just to be sure.

 

I did regap them carefully the proper way cause these arent like other plugs and it does start a TAD quicker but thats all I notice about the regapping.