Cylinder Head and Big Bore kit

[Andych]

Hi all
OK... a couple of questions.. looking at my cylinder head a number of the fins are corroded to the point of almost being powder. I can source a "rebuilt" head for A$270 but my 2 concerns are 1 - there is no valve cover with it... are they matched for cam bearing clearance.. and 2 - It looks like it has been blasted.. again main area of concern are the cam bearing surfaces. Pic in the ebay link.
https://www.ebay.com.au/itm/honda-cb-400f-head/222670986745?hash=item33d8399df9:g:pJgAAOSwrP9Z2ZEl

Second Question - Has anyone had any experience with these Big Bore kits from webike. they are more expensive than the CruisinImage kits but look to be better quality and are based on the Yoshimura 450 kit so they will be High Compression pistons.. most likely...lolhttps://www.ebay.com.au/itm/BRC-450cc-Bore-Up-Piston-Kit-HONDA-CB400F-2013/162943854098?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

I have my sights on another CB400.. just waiting for the price to become a little lower... it is a recent import from the USA with papers but the engine has been partially stripped.. they are forced to do this now in Aus du to "asbestos" gasket concerns...

Cheers

[Bryanj]

cover and head are not a matched pair and any blaster should know to only do the outside

[Andych]

Thanks for that... Problem is that too many people have home blasters and go at things like a bull at a gate..

Just realised the link for the Big Bore Kit didnt work..
Maybe try this one.
https://www.ebay.com.au/itm/BRC-450cc-Bore-Up-Piston-Kit-HONDA-CB400F-2013/162943854098?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

[Seabeowner]

The bearing surfaces of that head certainly look a bit dull. Abrasive blasting would surely be silly, but not sure about vapour blasting.