Hi All,
Have researched iridium spark plugs on this site but have seen no mention of an applicable part number that might apply to it. Also, a good, best, favorite place to pick up such an item.
Any help would be appreciated. Thanks.

Dick,

I bought mine from Matt at scootertrap.com , but as we all know he closed. Here is one link that I looked up and they seem to be about what most charge.

http://www.scootertronics.com/hosi600irspp.html

I changed mine out to the iridium and I need to do some maintenance on my scoot this winter. I hear they last a lot longer but probably don't do much else than last longer.

Thanks JeffR. I'll giv'em a look-see. Also, one more question if you don't mind. When you switched over to the iridium plugs, did you have the problem (as one SWinger had) of a big jump in idle rpm's??

Dick,

I didn't have any problems at all. I kind of thought it may have smoothed it out some, but then it could have been just because I changed out to new plugs. But I really think they are just a plus since they last so long. Also, I have never bought from this place but they seem to sell many things so I wouldn't have a problem buying from them if I need something. It was just a search I did to try to find a place that sells them. I sure do miss Matt at scootertrap.com. I ordered quick a bit from him.

You might look for a crossover from NGK to Denso. A couple weeks ago I wanted to change iridium plugs on my car and at all local parts houses and some online ones they were $25 each: found Denso's for $12.

Edited to add: Looked it up and Denso is IU20 but price if anything appears higher than NGK which can be had for $9 each.

Thanks to everyone for all the information!!

DickO, I put Iridium plugs in at 8,000 mls. Now got 15400mls up. First thing i noticed revs dropped slightly at tickover(only slightly). Perfomance wise, very pleased with them never any missfire or overrun.Someone said they will last up to 50,000mls. Not sure about that, I'll be checking them out when i do the 16,000ml service. In the UK they cost the same as NGK ordinary plugs, about £8. Normal cruising speed for me is 60mph.

The ones I recently replaced in my car had 71,000 miles on them and looked practically like new....they would have gone on for another 30K most likely. I had a slightly rough idle (tickover....I like that word) and thought new plugs would help. They didn't. I'm told the throttle body needs cleaning.

I would expect them to last 50K in the SW, at least.

What would tell you they need replacing, honda silver?

I haven't looked at these plugs since i fitted them, i presume they should look as the ordinary plugs should IE: brick red tip, and no sign of oiling or weak mixture. The other point was, as the gap was set at manufacturer, would it be safe to regap ,if needed, as i was told they are quite fragile(or at least the centre electrode is). I'm a tightwad so would not buy a new set unless i was sure i needed them.

Unless you are very careful, I wouldn't touch the gap on an Iridium plug. The centre electrode is a thin Iridium wire which can snap very easily. The Iridum electrode has negligible wear.
It's the ground (side) electrode, made of nickel plated steel or sometimes platinum tipped, that wears.
If you insist on regapping Iridum plugs, use the correct spark plug adjustment tool to bend the ground electrode away from the centre electrode if the gap is too small, or tap the ground electrode on a block of wood to narrow the gap if it is too large. Spark plug gap naturally widens as the ground electrode wears.

Thanks Bigbird

So... if a person purchases iridium plugs, then they just stick them straight into the engine?? Do they come already pre-gapped??

Just my two cents worth, but the best thing that happened to spark plugs was taking the lead out of the fuel. Next was fuel injection.

Sparkplugs do come pre-gapped, but I always check them. Who knows, they might have a knucklehead like me drop them somewhere along the line.