83 KZ1100 Ltd Spark plug port question

Hey all. New rider here with some questions. Recently bought an 83 kz1100 ltd and ran into a snag. The threading on the #4 spark plug hole is shot. Would a heli-coil be a good fix? If so, would I need to remove the cylinder head in order to fix it? Really hoping I don't have to.

Time-serts are better. You may want to read all the way through the link below as it contains related information. Ed

www.kzrider.com/forum/2-engine/594147-an...?limitstart=0#634081

www.timesert.com/

Thanks. Can you tell me exactly what size I would need?

rarewolf wrote: Hey all. New rider here with some questions. Recently bought an 83 kz1100 ltd and ran into a snag. The threading on the #4 spark plug hole is shot. Would a heli-coil be a good fix? If so, would I need to remove the cylinder head in order to fix it? Really hoping I don't have to.

Hello, rarewolf, and WELCOME to KZr!

Are the threads completely stripped out so that there's no possibility of re-tapping the existing hole?

Or is it more a matter of the hole being cross-threaded?

Where cross-threading makes it virtually impossible to align re-cutting from top of the hole, there's a "reverse tap" tool available that starts with the good threads at the bottom of the hole, whereby the tap remains aligned when re-cutting upward through the cross-threads.

The reverse tap tool may be used without removing the engine head.

With the engine head removed, a normal re-cutting tap may be used beginning at the deep end (piston side) of the hole.

Good Fortune!

The threads aren't quite completely stripped all the way through, but they're pretty badly stripped at the top of the hole. This bike sat unused and neglected for I don't know how many years. I'd wager the plugs that were in it when I bought it had been there for over 10 years. I've looked into Time-Serts and I think I'm going to go with that option.

Thanks for the reply!

Update.

Time-Serts are hella expensive. Went with the Auto-Zone equivalent (I know, I know...) and it worked like a charm. Thanks for all the help!!