YZ 426, using replacement threads in the oil filter cover bolt area.

So, it finaly happened. The oil drain bolt in my YZ 426 pulled it's threads out of the case. I knew it was coming as the guy I bought the bike off of told me they were "kinda loose" what ever that ment.

But anyway, what is the prevaling opinion on using a replacement thread kit in this area. I know the little prong off the thread coil will be importaint to find but will the threads hold well enough to do this or am I stuck with buying a case half?:D:worthy::prof:


Same thing happened to my '02...reported cause was user neglecting to flush out the threaded holes with WD (or the like) during oil changes.

I was able to 'heli-coil' all three holes back to the original size without removing cases and got all new bolts (OEM) and it's good as new. :worthy:

Helicoils will last longer and be stronger than the original thread was, as far as finding the little tang goes, I modifed a pair of small needle nose pliers to grab it with, work it back and forth and plull it out, I also installed magnetic drain plugs when I was done.


Same thing happened on my 02 426. Helicoil is the way to go!

Ok guys, sounds good. But what size should I look for? Also where did you buy your Helicoil sets?



If we are talking about the oil filter housing they are 6 mm.We just go to the local auto parts house and get them!Napa or the like will have them.

Here is what I used on my older 426's. I think a better design


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