NOS cylinder head

[exvalvesetdabbler]

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 I have uncovered a NOS cylinder head that I had stowed in the loft 30 years ago.  Originally bought it  because mine had a few iffy threads for the rocker cover bolts.

What I'm not sure on is the valve seats. Valve guides are present.  Looking at the parts list it does show valve guides as being  included in the part number and available separately.  If it is a factory fresh head would the valve guides have been reamed to size an the seats ground concentric with the guide.

Taking a used ex valve it goes in quite easily, just the lightest of a push and gravity does the rest.

The reason for it being cheap at the time is the exhaust port stud holes are untapped.  M5 drill bit drops in M5.5 is a tight fit and only goes in a few mm.  So probably right for tapping.

Regards
Dave

[Bryanj]

Yes the guides and seats were done at factory and the exhauts studshave "self tapping" threads on the head end but personally would tap 6mm and fot m6x50 stainless studs from fleabay

[exvalvesetdabbler]

Thanks Bryan,   Already have some studs that I made from 316 stainless but I chickened out when it came to extracting the ones from the working engine.

Edit.  I tried removing studs from a scrap head, 4 came out, one snapped off - gave up but at least I had an old one for a pattern.

Thanks
Dave

[Laverda Dave]

Come on Dave, put me out of my misery......how much was that NOS head when you bought it 30 years ago?

[exvalvesetdabbler]

Come on Dave, put me out of my misery......how much was that NOS head when you bought it 30 years ago?

Probably around the 30 quid mark, cheaper than helicoiling a load of threads if the worst happened.  Was a lot of money in them days!

There's a rocker cover with tappet covers as well, think it was cheaper. This was  before DSS got going properly. Most stuff was the small ads in MCN.

Dealers were just about giving stuff away in the early 90s

Dave.

[TrickyMicky]

If you want to treat yourself for Christmas, Megazip are showing a new OE cylinder block for $2844 US.

[exvalvesetdabbler]

Seems that spare parts could be a better long term investment than complete bikes.

Just regret not getting a set of barrels and camshaft at the time,  had to feed the family and pay a mortgage (interest rate ca. 13%,) at the time.

Regards
Dave

[McCabe-Thiele (Ted)]

About 5 years ago my BiL started buying old Japanese bikes, he dismantled them selling the spares.
He would travel to the likes of Wales for bargains.
He gave the business to his son a couple of years ago, it's morphed into sales of bike spares for somewhat newer bikes as a sideline to his day job.