Topic: Buying Valves

[DanJ]

I'm going to need new valves for my 73 K-3 are valves from Cycle-X a good choice?

Thanks

Dan

[DanJ]

Ok does any one have any suggestions on which valves to buy?

[70CB750]

I bought valves from CycleX for my F engine, they seem to be nice, did not install them yet.

Vintagecb750 carries valves too, if i needed valves for K I would likely go with those 

[HondaMan]

I just finished rebuilding an F2 head (twice) that has the "high performance" CycleX valves with a coating of some kind on them. After the engine was run a couple of hundred miles, this [thick] coating wore off the stems and left the valves very loose in their guides. The clearance had started at .0010" intake and .0020" exhaust: by the time the head came back to me they were nearly .0060" intake and even more on the exhaust side. I had to remove the valve guides, which had just been resized using bronze liners, and replace them with oversized CycleX guides because after I finished polishing off the REST of this coating, the valve stems were slightly below Honda's new-spec size.

Once all the rest of the coating was removed from the valves, they look like nice stainless-steel ones. I polished their stems and faces smooth, sized the new valve guides to fit appropriately, and will be sending the head back into service.

I don't know what the coating is/was, but it doesn't last long in the guides and it REALLY holds carbon tightly to the valve faces. It is about .0005" to .0008" thick on the surface, so when it wears off in the guides it adds about .0016" extra clearance, quick. 

[flybox1]

Glad I decided to go with a set of NOS guides for my F2 head.
Unfortunate to hear this as cyclex is usually a go-to vender.

[HondaMan]

Glad I decided to go with a set of NOS guides for my F2 head.
Unfortunate to hear this as cyclex is usually a go-to vender.

I don't usually have anything but good to say about Ken's stuff there at CycleX. I don't know what this was about, or the coating: it sure didn't do what I expected of it? So, I went back to the tried-and-true method, it just needed undersized guides to get there. But, CycleX had those, too, so it worked out OK except for taking the engine down twice and shipping it back & forth to the owner, poor guy.

[70CB750]

Thanks, Mark 

Now what should I do with the F2 valves I have on my bench, waiting to be installed in the head with APE guides?

Should I be proactive and polish the coating off?

[PeWe]

OK, so I can "look forward" to another repair when I used similar EX 28mm valves?
ENV-017
http://www.cyclexchange.net/Engine%20Parts%20Valve%20Trane.htm

I'll see blue smoke or just feel the smell of burned oil during deceleration, heavy throttle and sudden throttle off, when twisting the throttle again check the mirrors as when driving a German or even worse, British Ford from the 70's?

[DanJ]

I just finished rebuilding an F2 head (twice) that has the "high performance" CycleX valves with a coating of some kind on them. After the engine was run a couple of hundred miles, this [thick] coating wore off the stems and left the valves very loose in their guides. The clearance had started at .0010" intake and .0020" exhaust: by the time the head came back to me they were nearly .0060" intake and even more on the exhaust side. I had to remove the valve guides, which had just been resized using bronze liners, and replace them with oversized CycleX guides because after I finished polishing off the REST of this coating, the valve stems were slightly below Honda's new-spec size.

Once all the rest of the coating was removed from the valves, they look like nice stainless-steel ones. I polished their stems and faces smooth, sized the new valve guides to fit appropriately, and will be sending the head back into service.

I don't know what the coating is/was, but it doesn't last long in the guides and it REALLY holds carbon tightly to the valve faces. It is about .0005" to .0008" thick on the surface, so when it wears off in the guides it adds about .0016" extra clearance, quick. 

Good to know, the coating I believe is DLC (Diamond Like Coating) which if coated correctly should be hard as hell. I haven't ordered any yet so if anyone has had good luck with a particluar valve please let me know. I know there is Kibblewhite but they want like $40 a valve.

Dan

[70CB750]

Truth be told I noticed the coating coming of on the stem after short test lapping of the seat.

[70CB750]

I wish I had micrometer. This is out od the league for my vernier caliper and also the noname electronic caliper.

Anyway, I polished the coating off the end of the valve, but it still measures the same as the coated stem (within 0.01mm on the electronic caliper) I believe I will take my chances and install valves coated.

Actually it does look more like blacked than coated, maybe these valves are just surface finished without additional coats.

[Big Jay]

Check out this link;  http://forums.sohc4.net/index.php?topic=131154.0
Nothing else out there compares to these new valves, and the price is right at $24.95 ea.

[70CB750]

Nice pitch, but I am building F3 engine.

[tlbranth]

Not criticizing, just asking: since stainless is not as strong as carbon steel, and since valves don't rust, what's the point in making valves from stainless steel?

[HondaMan]

Thanks, Mark 

Now what should I do with the F2 valves I have on my bench, waiting to be installed in the head with APE guides?

Should I be proactive and polish the coating off?

Check the clearance, for sure. I had special inserts done for this head the first time (bored them, installed bronze liners, reamed to fit) because it was otherwise in good shape and the "F" guides are more completely supported than the earlier heads (read: stronger, longer fitting into the head, probably Honda hoping for better cooling), so it seemed like a good idea. When it was all assembled, the clearnace was .0010" on the intakes and .0016" to .0020" on the exhausts. This grew a LOT, which appeared to be from the grinding action of the stuff left in the valve guides after it came off the stems. It rather resembled lapping compound, in a way, because the top end bottom end of the old guides were worn in a bell-shape, wider toward the ends, by as much as .006". It was quite a shock!

The all-bronze APE guides are a more dense type of bronze than the liners I used the first time, although these liners are well known for their life (I have 160k on them in my Ford 200 CID and almost that much on them in my Ford FE 390 engines) and self-lubricating, low-friction nature. That's why this was such a surprise to me!

I don't know which type of bronze the CycleX undersize/oversize guides are made from, but I do know they are harder to ream to size than the APE, from experience. I end up reaming them undersize, then honing to final size, instead.

My biggest concern is the coating's loss in use: it came off unevenly, wearing off on the side opposite the rockers at the top (i.e. sideways pressure scrape) and on the opposite side at the bottom. This is also where the guides showed their wear, as shiny burnished (or polished) sites. I still have the old guides here, may end up cutting them open at some point for examination up close?

The other 'annoyance' of it was in how difficult it was to remove the burned-on oil and carbon. Usually I chuck up the valves in my lathe and spin it off with a pocketknife or utility blade, comes right off. On these, the carbon was so tightly bound to the coating that I had to cut it off with a carbide bit(!). This naturally disturbed the coating on the valve faces, so I ended up giving them all the mirror treatment afterward. Took me a whole Saturday, but I felt like it was my "fault" as I had built the head for the owner previously. He wanted to use these valves specifically (it's a higher-perf "F" bike build), and I was glad to oblige: next time I see these I'll start by removing the coating in the guides area, though.

[70CB750]

Thanks, Mark!  I still have time before they go in, I will invets into micrometer and go by that.

Tibrant: it is a known fact that shiny ammo shoots better - maybe that´s the reason for SS? 

[kmb69]

Not criticizing, just asking: since stainless is not as strong as carbon steel, and since valves don't rust, what's the point in making valves from stainless steel?

Jay advertises:  "APE stainless steel valves are precision manufactured from aircraft quality Inconel based stainless steel......All stainless steel valves feature hard chrome stems for extra long stem to guide life."

While he is calling them "stainless", Inconel is not your mother's soft stainless. It can be heat treated to 185,000 KSI tensile, 45Rc depending on the particular alloy/chemistry. I am curious why he has to "hard chrome" the stems. Galling? Stiction? Maybe not necessary in bronze guides but maybe necessary in some of the harder steel/stellite guides. Lots of "stainless" and titanium valves being used in performance autos.

Not hawking for Jay, just saying/asking.

[tlbranth]

Not criticizing, just asking: since stainless is not as strong as carbon steel, and since valves don't rust, what's the point in making valves from stainless steel?

Jay advertises:  "APE stainless steel valves are precision manufactured from aircraft quality Inconel based stainless steel......All stainless steel valves feature hard chrome stems for extra long stem to guide life."

While he is calling them "stainless", Inconel is not your mother's soft stainless. It can be heat treated to 185,000 KSI tensile, 45Rc depending on the particular alloy/chemistry. I am curious why he has to "hard chrome" the stems. Galling? Stiction? Maybe not necessary in bronze guides but maybe necessary in some of the harder steel/stellite guides. Lots of "stainless" and titanium valves being used in performance autos.

Not hawking for Jay, just saying/asking.

Oh

[timbo750]

Check out this link;  http://forums.sohc4.net/index.php?topic=131154.0
Nothing else out there compares to these new valves, and the price is right at $24.95 ea.

Jay
I had a look on the APE web site and the only valves I could find where $39.95 ea, is the price you mentioned right if so do you have a link for them?

[lrutt]

what about Kibblewhites?? I thought they were like the defacto standard to go with?? or do they not make SOHC valves?

[Jerry Rxman Griffin aka MuthaF'er]

Kibblewhite does make valves. 6.5mm stem standard size stainless, 6.5mm stem oversize stainless, 5mm stems oversize, Black Diamond, etc. Hoping my info is current. My Kibblewhites came with lash caps and Jay's does not need them??

Jay has raised the bar as far as options go. Thanks again Jay.

[timbo750]

I was under the impression that Kibblewhite made the valves for cycleX but I could be wrong here.

[MRieck]

I just finished rebuilding an F2 head (twice) that has the "high performance" CycleX valves with a coating of some kind on them. After the engine was run a couple of hundred miles, this [thick] coating wore off the stems and left the valves very loose in their guides. The clearance had started at .0010" intake and .0020" exhaust: by the time the head came back to me they were nearly .0060" intake and even more on the exhaust side. I had to remove the valve guides, which had just been resized using bronze liners, and replace them with oversized CycleX guides because after I finished polishing off the REST of this coating, the valve stems were slightly below Honda's new-spec size.

Once all the rest of the coating was removed from the valves, they look like nice stainless-steel ones. I polished their stems and faces smooth, sized the new valve guides to fit appropriately, and will be sending the head back into service.

I don't know what the coating is/was, but it doesn't last long in the guides and it REALLY holds carbon tightly to the valve faces. It is about .0005" to .0008" thick on the surface, so when it wears off in the guides it adds about .0016" extra clearance, quick. 

Mark...what springs were in that head and what was seat pressure? I am very curious about that.
  Mike

[Maraakate]

I just finished rebuilding an F2 head (twice) that has the "high performance" CycleX valves with a coating of some kind on them. After the engine was run a couple of hundred miles, this [thick] coating wore off the stems and left the valves very loose in their guides. The clearance had started at .0010" intake and .0020" exhaust: by the time the head came back to me they were nearly .0060" intake and even more on the exhaust side. I had to remove the valve guides, which had just been resized using bronze liners, and replace them with oversized CycleX guides because after I finished polishing off the REST of this coating, the valve stems were slightly below Honda's new-spec size.

Once all the rest of the coating was removed from the valves, they look like nice stainless-steel ones. I polished their stems and faces smooth, sized the new valve guides to fit appropriately, and will be sending the head back into service.

I don't know what the coating is/was, but it doesn't last long in the guides and it REALLY holds carbon tightly to the valve faces. It is about .0005" to .0008" thick on the surface, so when it wears off in the guides it adds about .0016" extra clearance, quick. 

You ever see that CycleX article that says you're wrong and the machine work you did was inferior?

http://cyclexchange.net/Fact%20or%20Fiction.htm

This cylinder head was sent to us to install on a customers motor.
Coincidentally, this cylinder head was done by the same person that questioned all valves with nitrite coatings or black diamond coatings. (Above mentioned forum gibberish)
If you look closely at the photos, you will see used valves that have been reground by a shop that needs a new valve grinder. Check out how choppy and uneven the lapping lines are.
Secondly, the valves seats have the same chatter, choppy and uneven finish.
Thirdly, these valves have clearly lead a hard life and should have been replaced.
Also, take a look at the dirt removed from the inside of the valve guide. So, this guy had a problem with some nitride valves? Maybe he should clean the engine components before assembly.
The exhaust guides are worn and should have been replaced.

Summary: The only new items in this cylinder head were the valve seals. this head was assembled with the 40+ year old valves, guides, springs and all should have been replaced.

Worst part, the customer was charged almost $700.00.

Curious your response.

[rotortiller]

New spec from a factory manual:
intake new valve guide/stem clearance     .0004-.0012"
exhaust new valve guide/stem clearance  .00016-0024"

Clearance Limits .0032" and .004" respectively

Two sides of a story, take with a grain of salt as feelings get hurt easily and a spanking happens lol. Truth is usually in the middle. lol Personally I like oil to do the valve guide/stem lubricating in the clearance space.