What do you guys gap plugs at with the dual side ground straps (NGK) cant remember the # 08 R1 Yamaha? Thanks Dave

I've changed my kawasaki ninja 250r sparkplug from stock to a DENSO Irridium type. now once in a while when I start my bike a huge explosion comes out from the exhaust pipe. I never had that from the stock plugs. What could cause that? Air temp? buildup of gases overnight? This happens 3 out of 10 times and usually on early morning starts. Is this a bad thing?

This won't apply in your case, maybe, but the guy that builds my ignition systems for me, tells me NOT to use Iridium spark plugs, he says that they do their magic with the negative voltage, from a 2 out coil, so on a 2 out coil, one wire is positive, the other negative, so it kills itself, so he put me back on the economy priced plugs, and it does run a lot better, he also fixed me up with a 180* pickup, vs the std 120*, so now all 4 plugs fire at the same time, which works great, keeps the unburned alky from collecting, it sounds a bit different, but it sure is quicker on the get up and go end! Bob!