Chipped valve guide

[ChowderV4]

Stripping a head on a motor I'm. Working on and have come across a chipped inlet valve guide.
Doesn't look to be cracked and I have no idea how long it's been like this, there are no marks on the pistons or bores from the missing peice.

The bike ran fine previous to taking it apart so what is anyone's thoughts.
Leave it or replace?
I'm Fitting new stem seals at the moment

[banner001]

I suppose that as long as the cracked bit doesn't extend up into the head, and as long as it's not scratching the valve stem that it's probably fine for a road bike, race bike I would change it...bit less stress in a road engine.

If you can change it I would still change it though...you will need a pressing and installation tool as well as a valve guide reamer

[ChowderV4]

Yeah that was my thoughts, no idea how long it's run like this. Its doubtful it's recent as there is no evidence of any marks on pistons or cylinder head of the broken peice.

I'm taking it to work to inspect it better, it doesn't look like there is a crack, the valve came out perfectly fine too just dt like any of the others too.