Topic: Cam chain adjuster bolt broke need HELP

[Gentlemanjim]

My CB400F with 10,000 miles had the cam chain adjuster bolt broken off flush with the recess in the block.  I attempted drill it for an easy out extractor, but the bold is so hardened that all drill bits cobalt failed to make even a small dent.
1. How can I get it out?
2. How did it brake off did the Previous owner brake while loosening?  I can't see how it would break while tightening as its just push against the spring mechanism.

HELP!!

[ekpent]

I am not a 400 guy but have seen threads about this problem. Here is a starter thread to read till the real Gurus arrive   http://forums.sohc4.net/index.php?topic=35331.0

[Bodi]

Well, it's a weird bolt - Google "cb400f cam adjuster bolt" and you'll see what I mean - but I have never found a hardened one. The thread that the lock nut is on is not the thread that tightens the bolt against the adjuster rod. Maybe if you can cut a slot in the end, a screwdriver or even an impact driver will get it out? A dremel should be able to cut a slot.
If it broke off flush, it's broken in the 8mm thread or where those threads end and the bolt gets thinner. Either way, it should be possible to convince it to come out. Unless someone has used some non-original bolt it should not be hardened to where it can't be drilled for an ez-out but I would go with the slot first - breaking off an ez-out off gives you definitely hardened steel to deal with. And the small ones are very easy to break.