jprost98
XS400 New Member
Hello everyone, I just purchased a project Yamaha XS400 a couple of weeks ago and am going to turn it into a cafe racer. While going through it to get it started, I needed to replace the plug caps and figured I would replace the plugs while I was around that area. I ordered the NGK plugs off of MikesXS. When I compared them to the plugs that are in the bike now, the plugs I ordered are much smaller. The plugs that are in it are Champion N4C. Does that mean that my bike has a different top end on it? Or maybe it is a different year than what I am thinking it is? The VIN stamped on the neck starts with 4R5, which from what I looked up is a 1981 model. Any help and clarification would be appreciated, thank you!
EDIT: I think I figured it out. The NGK plugs I ordered were 10mm thread whereas the Champion ones are 14mm thread. Need to order the OG BP7ES and return the NGK ones I guess.
EDIT: I think I figured it out. The NGK plugs I ordered were 10mm thread whereas the Champion ones are 14mm thread. Need to order the OG BP7ES and return the NGK ones I guess.
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