Yep, sounds like your plug is bad. You have original plugs from the era, but Bosch has changed their naming scheme since then. You're looking for W4AC. Vech has them, or you may be able to find them locally. Good luck!
I used Bosch plugs with great success for years. When they became difficult to find I switched to Champion 306 (L86C). They work fine for me, easy to find and cheap. These are the short reach plugs for the older heads, I am sure Champion has one for the newer long reach heads.................Comet
Greetings, I have a plug on my 65 R50 which is not sparking from the center of the electrode but around the base of the electrode next to the ceramic cone. I need to find a replacement plug but cannot find anyone with this plug or it's equivalent. What should I be asking for? The plugs I have are Bosch W240T1. I love the forum and read everything to keep my ride in shape. 30,000mi. and counting.
Thanx,GlennC biggbeers@hotmail.com
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