Well I have to say, that if the general appearance of the spark plugs has anything to do with it, the fuel pack is doin very well. Pulled my plugs after a 1k mile road trip, and much much HOT Va Beach summer riding (last season of course), you know... Like it owes you money. My plugs were only slightly gray in the electrode and the bar. Anywho, I want new ones, and can't for the life of me find the correct size. Also does anyone here know of a brand/style to stay away from or anything??? I was thinking some kind of Bosch. I like them in my truck... Any help would be great.

Thanks

 

You can take either of the 2 below and cross ref them to Bosch.

Champion - RA8HC
NGK - DCPR7E


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the harley number will cross reference.
Non are made in the usa anymore.
NGK seem to work best on my big twin.
A good parts person at NAPA will be able to look them up for you, based on year, model, engine size.

 

As far as brands go, I am partial to NGK.

 

Run down to the HD dealer and tell them what bike you have. The HD plugs are only a few bucks.

 

x2 had good luck with them on everything dirt bikes, sport bikes, boat, Harley ect.

 

Just curious. Since you mentioned that the original plugs worked great....why change?

The HD plugs that say Harley-Davidson on the side of them are made by Champion.

Champion - RA8HC, to be specific.

 

A regular old Autolite 4164 will last as long or longer than most and you can buy them at most auto parts stores.
Stay away from any of those fancy overpriced plugs they do nothing other than drain your wallet.

 

I replaced the plugs in my bike as soon as I bought it. Got HD plugs from my local Indy shop. They are still working great! Started up after sitting for 2 mos and no problem. Put around 10k on them so far.

 

The factory ones do work. However I need a hotter spark for the tune I have (damn efi, lol). I have black MSD wires waiting and the new ignition system on the way and need some plugs that can take the extra juice.

Thanks for all the references.