spark plugs

[rocket23]

 welp Glad too be here, first off. second, the dimwit at autozone/napa.......one of the two,Gave me 4164 sparkplugs for my 1988 k-100lt. The google seach has them as 4164. Lining them up with the ngk's that were in there when I bought the bike, the thread/electrode depth on the autolite are 1/64th longer than the ngk. Trouble is most places have no listing for the bike.....being an '88. Should I replace with the 4163's or go iridium bosch? Which bosch plug would that be btw. Thanks in advance

[Scott_]

Read this thread in the Lieberry.
http://www.motobrick.com/index.php/topic,1563.0.html

The only thing to be aware of is that some plugs do NOT come with the top caps. You will have to source them separately.

[JamesInCA]

AutoLite's web site lists the 4164 as compatible with the Bosch X5DC, which is what comes in your bike. Both have 3/4" reach.

I suspect the 1/64" you're seeing is just manufacturing variance. I'd go ahead and stick it in.

Be sure it's gapped appropriately. I just got three 4163s that were wildly different. It's .6 - .7mm on the K75 (.024" - .028").