FZRSupport: the FZROnline Archive

So I popped out the spark plugs I bought with the bike to replace them. I looked at the old ones to compare them to the new ones and the old ones are course thread and the new ones are fine thread. Has anyone ever ran into anything like this? I went to a local shop n they said they have never heard of anything like it. Tried to post a pic but it says the file is to big.

What year FZR600 in what country?

91 fzr 600 USA

Someone probably stripped-out their plugs and threaded in coarse ones.

I assume the shop didn't have the same plug #'s as those you removed?

Yes cr9e. Same as the ones I bought to replace them

There is only one thread for that plug.

I would suggest the new plugs are snide copies and should be returned for refund.

Yeah something is not adding up. Weird.

Ya I took a pic of the top of the head so I could see down the spark plug holes and some1 must have stripped out so old plugs n put helicoils in them. I think I'm just gonna get a dye n try to re thread new plugs to course thread. Not sure what else to do at this point

Im pretty sure oem is supposed to be cr8....not cr9. I have a 92 of the same bike, so my guess is that theu ruined the plug ports on the head and had to tap them out themselves with a larger plug.

Ya that's what they did. Had to go buy a tap n dye set to get new plugs into it. But since then it runs great