Topic: Valve ID

[Tom R]

I received a “recently rebuilt” head today with little knowledge from seller what’s in it.
It has Ti retainers, aftermarket valve springs, presumably kibblewhite, and the valves pictured.
Cycle-x superflow valves? The exhaust valve looks different than pics on their website though.
Very little wear…. Intake is 0.2595 and tapers to 0.240, and exhaust is 0.2575 and tapers to 0.235 near the head.
They appear to be nice.
Also included in this buy was a cycle-x CX-2 camshaft with some oil starvation issues. Salvageable or garbage?

-Tom

[Tracksnblades1]

Is your .2595 consistent on the x y axis of the valve stem…?
The necked  down part is to increase flow in the port…

If your valve stems actually have .019 taper as you posted they’re junk…
I reread your post as the necked down area was what you were indicating “tapered down” to .240…?

[Tracksnblades1]

Looking at the bottom picture of you valve stem tip…..

Did it have lash caps for the valve stem tips..?

Or Is that the tip’s finish…? Or is my IPad making it look like a hack.saw finished the stem height…?

Wondering how long your rocker arm adjuster going to last .without lash caps…?

Cam looks ran dry…?

[Tom R]

It’s a consistent 0.2595… thinner in necked down area.

[Tracksnblades1]

It’s a consistent 0.2595… thinner in necked down area.

Yea, I see you edited your post after I had my junk out on the limb…

Is the valve stem tip that rough or is it my iPad.?

[Tom R]

No lash caps that I know of. The picture makes it look worse than it is, but agreed that it’s not as smooth as I’d expect.

[Tracksnblades1]

No lash caps that I know of. The picture makes it look worse than it is, but agreed that it’s not as smooth as I’d expect.

The old valve grinders had a provision for grinding the tip off for a particular installed height. (Ford Chrysler non adjustable stuff).  You could heat the tip red and quench if it was required…

I don’t think your chrome adjuster tip will like that finish.. Actually I’ve never seen a tip the didn’t look like a mirror if properly prepared…sure they just missed that one…

??

[newday777]

I received a “recently rebuilt” head today with little knowledge from seller what’s in it.
It has Ti retainers, aftermarket valve springs, presumably kibblewhite, and the valves pictured.
Cycle-x superflow valves? The exhaust valve looks different than pics on their website though.
Very little wear…. Intake is 0.2595 and tapers to 0.240, and exhaust is 0.2575 and tapers to 0.235 near the head.
They appear to be nice.
Also included in this buy was a cycle-x CX-2 camshaft with some oil starvation issues. Salvageable or garbage?

-Tom

Howdy Tom welcome to the forum
So was this an ebay purchase or from a local sale near you? I see you have your location as Chicago, you might want to drive up to see Kenny at CycleX or ship the head and cam up to have him look it over but my thoughts are also very questionable on the cam bearing surface, how are the cam tower bearing surfaces? It does look like it was starved for oil.
I've not seen valve ends serated like that one either.

BTW I looked through your posts(to try to see what you have for a bike) and see you haven't introduced yourself and your bike in the new members section.

http://forums.sohc4.net/index.php/board,58.0.html

Another good thing to do is to start a project thread on your bike in the Project Shop. It's a good way to keep all your questions and information on the build in one place.

http://forums.sohc4.net/index.php/board,103.0.html

[Tom R]

No lash caps that I know of. The picture makes it look worse than it is, but agreed that it’s not as smooth as I’d expect.

The old valve grinders had a provision for grinding the tip off for a particular installed height. (Ford Chrysler non adjustable stuff).  You could heat the tip red and quench if it was required…

I don’t think your chrome adjuster tip will like that finish.. Actually I’ve never seen a tip the didn’t look like a mirror if properly prepared…sure they just missed that one…

??

I have an old Sioux valve grinder in my garage that does this. I just acquired it a couple months ago and haven’t had time to play with it though. Fortunately I have plenty of old valves to practice on.

[Tom R]

[/quote]

Howdy Tom welcome to the forum
So was this an ebay purchase or from a local sale near you? I see you have your location as Chicago, you might want to drive up to see Kenny at CycleX or ship the head and cam up to have him look it over but my thoughts are also very questionable on the cam bearing surface, how are the cam tower bearing surfaces? It does look like it was starved for oil.
I've not seen valve ends serated like that one either.

[/quote]

It was a local buy of the take it or leave it variety. It was cheap, and springs and retainers alone made it worth it. The intake guides are in spec, the exhaust need to be replaced.
The carrier is junk. I have several good ones to pick through though.
The valves seem to have little wear, and the 4 I checked are straight…. But the wear and finish on the tips is odd.

I know cams are repairable, but can be expensive…. Just wondering if it’s worth even looking into it.

[Tracksnblades1]

No lash caps that I know of. The picture makes it look worse than it is, but agreed that it’s not as smooth as I’d expect.

The old valve grinders had a provision for grinding the tip off for a particular installed height. (Ford Chrysler non adjustable stuff).  You could heat the tip red and quench if it was required…

I don’t think your chrome adjuster tip will like that finish.. Actually I’ve never seen a tip the didn’t look like a mirror if properly prepared…sure they just missed that one…

??

I have an old Sioux valve grinder in my garage that does this. I just acquired it a couple months ago and haven’t had time to play with it though. Fortunately I have plenty of old valves to practice on.

Some of those old Sioux’s were decent.  I don’t think I’ve ever used one that liked worn valve stems or guides though..
I doubt if your seat grinder has small enough pilots for your guides unless someone purchased them back in the day…

One of the quickest way to check the guide wear was to try the standard, +0.001, or.002, etc pilots to see what fit snug in the old guide…the bore gauge was still the most accurate the the oversized pilot would let you know in a hurry whether your guides were junk…

The valve face grinder may have a fine stone included that will clean up your valve tips.. Hope your Sioux has the flood coolant option…if you knew if your tips were hardened and how deep would be a benefit.. it looks like yours are coated so that would be another learning curve..if they’re stainless they probably can’t be hardened anyway…some stainless valve used to come with stellite tips welded on for long life..

It looks like your valves only have a face angle. No back cut angle or top cut angles to promote flow. But maybe the sohc cylinder head ports don’t require that to get max flow…

Edit: I would dress the stone before using the side of it to polish your tips..

[PeWe]

I thought back cut valves was standard when porting heads.
My shop has always done that. A really cheap mod.

Here a set of new inlet valves a head will get when I'll get my thumbs out.  (CycleX SS valves).
It has today stock F2 in valves with very soft stems that was standard. Lash caps do not live long either but better to replace caps than the valves.

My shop made a back cut when I had other things there.

[Tracksnblades1]

Good looking valve PEWE.

What does the combustion chamber side of the exhaust valve look like?

[PeWe]

I hope this will not bring too much extra into this thread. Technical discussions are interesting.
CB750 Hemi !

This head has F2 in valves with lash caps.
Will get the valve on previous photo.
I need to measure assembly height on existing, test the shiny K valve and check if I need to change the shims under springs.
Not only to swap and wish for the best.
F valve might sit different with its different keepers and retainer.



[Head milled 0.50mm, MLS 72mm gasket]
#
#

Another head with same type of SS valves from CycleX, 34/28mm. They sell 33.5mm even cheaper today.

Chambers had to get some massage for 890cc piston domes, later milled 2mm when compression was too high and avoid double spark plug washers.
That engine need to be assembled to verify my guesses about OK compression.

[MRieck]

You are talking about the valve stem OD, not ID. As some one posted any real taper in the OD = junk. At first I thought you where talking about the guide bore. Those tips look like they were finished by dragging them down a sidewalk. I wonder about they're hardness too....they aren't Kibblewhite. You can grind them down .040 and put some lash caps on them. Like Per said the caps have a finite life but can be changed out. I always backcut the intake along with a slight undercut....it makes a difference.

[Tom R]

The Souix grinder sits on an oil pan and has an oil pump while running.
I was thinking of putting a back cut on the valves if I figure out my valve grinder. It may be old, but a new toy for me and in good shape. 
What angle is the back cut on your valves?
I do have a seat cutter as well… but you’re right that the pilots are all too big.
If I could find a 6.6mm pilot I might jump at it. It’s hard to justify spending too much though. I’ll prob only do one or two… three if if I’m lucky

[Tom R]

You are talking about the valve stem OD, not ID. As some one posted any real taper in the OD + junk. At first I thought you where talking about the guide bore. Those tips look like they were finished by dragging them down a sidewalk. I wonder about they're hardness too....they aren't Kibblewhite. You can grind them down .040 and put some lash caps on them. Like Per said the caps have a finite life but can be changed out. I always backcut the intake along with a slight undercut....it makes a difference.

7 of the valves have very little wear in the stem, but they all have that strange wear pattern on the tip. The stock valves I’ve seen have a round wear pattern from the valve spinning…. These have a straight line. Shouldn’t the valves spin?
Of course the last valve I took out was worse and had some galling. I polished the tip of that one pretty easily by hand with 1000 sand paper. Maybe too easily. How hard are the tip supposed to be?