YZ400f Timing chain tensioner??!!

I just recently bought a 1998 yz400f, its an awsome bike, runs great!

but i recently went to adjust the timing chain tension, and realized the cap bolt (the one that screws into the end of the tensioner) is broken off.

So basically my question is how do i wind the tensioner back up after i take it off? :thumbsup:

because to wind it, you have to take the cap bolt off.

(i dont want to take it off and not be able to wind it)

Thanks, Michael Cahill

I would remove the chain tensioner and then extract the screw from it with an "Ezy-Out". The screw does not bottom in the bore, so it should not be jammed in. In fact, you might even be able to pick it out of place with a scribe.

Be sure to put a copper washer on the new one.

Incidentally, one does not adjust the timing chain tension on a YZF.

what is a scribe?

well not adjust, but tighten it

A scribe is a sharp pointy device. A small pick or screw or anything sharp may work to turn it back out.

You do not tighten, loosen or adjust the cam chain, it is an automatic adjuster that is spring loaded. Or perhaps you have an aftermarket cam chain adjuster which is adjustable.

i see,

so the adjuster never will have to be adjusted?

(it never needs to be wound up occasinally?)

Absolutely never. It's as near a perfect design for a chain tensioner as I have ever seen in over 30 years as a professional mechanic.

Good to know... I was wondering that myself.

ah, got it!

thats good to know.

Thanks for the help, Michael Cahill

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