Topic: CycleX SuperFlow Valves

[74750k4]

Just starting a new thread, because the original (  http://forums.sohc4.net/index.php?topic=134463.75  )
drifted off topic.

Apparently the SuperFlows are a Super Blow.

[Nic]

Subscribed.

[Bailgang]

Subscribed. Not the news I wanted to hear because I have a new set of them here waiting to be installed. I guess now is the time to know this before I install them.

[Nic]

Subscribed. Not the news I wanted to hear because I have a new set of them here waiting to be installed. I guess now is the time to know this before I install them.

Absolutely don't use em, it's just not worth it.

[PeWe]

I have them in my K head (28mm exhaust valves) that happen to be off the engine waiting to be installed.
Is it a good idea to replace them?  The surface will otherwise fall off and destroy seats, guides ? I use a high lift cam CX-7
The head has harder springs installed 1983, maybe Action Fours......

I'll take them off later today and see what happened after garage revving sessions tuning the ignition and carbs. I have a bunch of old OEM exhaust valves. I might put them in.
- Sure it will work just grinding the coating off? Good procedure how to?
- Are KPMI BLACK DIAMOND VALVES better ?

[MRieck]

Before everybody gets their underwear tangled I would suggest finding out exactly what kind of "coating" is used on CycleX valves. The pics I saw on the other thread do not look abnormal including carbon pitting. I do not know who did the valve job but the valve face contact area looks very wide too....it should start at .060.
 There are a few other things to know too. #1 bronze guides do not last like cast iron.....period. I have seen them oval in under 5,000 miles and that is with guides from the 3 companies that supply them. That is also with Kibblewhite valves, 6.5 and 5mm stems.
#2 Forget about installed height and go with actual spring pressure on the seat and at max lift. Kibblewhite springs are set up to stiff IMO.
#3 CB750's have a steep valve angle and create a lot of side load....combine that with a cam that supplies .060 to .080 more lift and you are going to see a lot more wear especially with heavier valves and higher revs. You don't have these problems in modern bikes with vary shallow valve angles. You do have big problems with Harley heads and bronze guides because the reasons I listed are even worse (very heavy valves, .500 - .600 lift cams & huge valve angle). I know several shops that will not install bronze guides in a Harley head for those reasons.
 Kibblewhite valves have some type of DLC applied and yes...the treatment does wear at the areas of highest load. I have seen it many times. I have also seen their hard chrome gall up a little to. The old stainless Manley's and RC's weren't any better.
 So....before the bandwagon sets off I'd find out a bit more and consider the points I just made. If you want minimal valvetrain wear get iron guides (or some of the old RC steel guides though the length was way to short), use weak springs and a stock cam. I'd also highly recommend zinc additive too.
 I don't go for internet bashing in general...if I don't like a product I won't use it. If the CycleX valves were displaying variations in stem diameters, valve margins and head diameters that is one thing....that is real and measurable. There is too much speculation here IMO.

[PeWe]

...zinc.... lubrication good enough for the old engine type as a CB750, right?  High content of ZDDP.
- What lubrication has been used in those cases where problems are seen?  Without starting a XXXX thread
My head have the old steel guides. I have to inspect my valves.

I have the frame mod, no problem to take head off.. It will cost a  head gasket each time.

[brandEn]

I have Cycle X valves, springs, cam, and guides in my 78 CB750 F3 (TAO). The head was rebuilt by Ken himself and I am more than satisfied. I have about 5000 miles on it and she pulls strong and runs well. I have had the head off a couple times since the rebuild and never noticed anything negative. I am happy with my parts and Cycle X in general.

[iron_worker]

I would tend to agree with MRieck.

Before jumping on the hate band wagon there is probably a lot more research required. I'm running stock size super flow valves and so far they're holding up fine though I only have about 2k miles on them of a fair bit of high revs and CX1 cam.

It has been my experience that CycleX tends to put out a good product which they stand behind.

IW

[74750k4]

" I do not know who did the valve job but the valve face contact area looks very wide too....it should start at .060."

The valve faces were installed untouched, and compare perfectly in width to another full set of CycleX valves sitting here before me...



So the suggestion is slap it back together as is, and enjoy the ride???

I could go back to the stock springs, cam, and valves, at this point if that is what is being suggested. I don't like the guide wear I see though, and looks like those should be replaced...
with steel?

Not sure what to think.  Just want to ride!

[MRieck]

" I do not know who did the valve job but the valve face contact area looks very wide too....it should start at .060."

The valve faces were installed untouched, and compare perfectly in width to another full set of CycleX valves sitting here before me...



So the suggestion is slap it back together as is, and enjoy the ride???

I could go back to the stock springs, cam, and valves, at this point if that is what is being suggested. I don't like the guide wear I see though, and looks like those should be replaced...
with steel?

Not sure what to think.  Just want to ride!

Just to clarify...the guides were installed but a valve job was not done? The width of the 45 degree cut on the seat should be about .040 for the intake and about .060 for the exhaust. When you lap the valves the gray line on the valve should be around those values....it shouldn't cover the width of the valve face.
 Steel isn't a good material for valve guides especially exhaust guides. It holds heat and doesn't offer lubricity.
 This whole thing started about an F2 head if I remember correctly. Every one of those heads is/was/will be a problem. I have seen those with about .100 of play. And that is correct....    .100. I don't know how a valve stays in the head at that point.
 Honda warrantied these early on BUT was it a true fix? No because the replacement guides get smoked again. Why this whole exhaust guide wear happens has never been effectively explained to me. Perhaps the shortened valve length is a big contributor as the cam profile and different spring are certainly nothing radical. When I spoke about side loads on the valve I should have noted this is a real problem on rocker arm valvetrain. Possibly the shortened valve length exacerbates the problem. Shim/bucket arrangements place much, much less side thrust on the valve itself (like the Z1 and GS designs).
"Updated" guides have been mentioned.....I have a difficult time believing that even if a new part# was generated. As I mentioned.....warrantied guides get smoked too.
 So.....F2's eat guides....especially exhaust guides thanks to heat. I know that Kenny is working on a solution for this as he has seen it many, many times too. I have talked to him about it but am not at liberty to say much else.
 As for the coating....it is more of a surface treatment (meaning there is not much in way of surface build up)....I am not going to get into that either.

 

[70CB750]

I polished the coating off on one of my superflow valves in the area where it matters not - above the keeper groove - and i was not able to read any significant change in  the stem diameter using new micrometer. 

The difference was within measuring error.  That's why I went ahead with the valve installation.

[74750k4]

" I do not know who did the valve job but the valve face contact area looks very wide too....it should start at .060."

The valve faces were installed untouched, and compare perfectly in width to another full set of CycleX valves sitting here before me...


"This whole thing started about an F2 head if I remember correctly. Every one of those heads is/was/will be a problem. I have seen those with about .100 of play. And that is correct....    .100. I don't know how a valve stays in the head at that point."

So maybe I should be jumping for joy they only have .008" !!! 



So the suggestion is slap it back together as is, and enjoy the ride???

I could go back to the stock springs, cam, and valves, at this point if that is what is being suggested. I don't like the guide wear I see though, and looks like those should be replaced...
with steel?

Not sure what to think.  Just want to ride!

Just to clarify...the guides were installed but a valve job was not done? The width of the 45 degree cut on the seat should be about .040 for the intake and about .060 for the exhaust. When you lap the valves the gray line on the valve should be around those values....it shouldn't cover the width of the valve face.
 Steel isn't a good material for valve guides especially exhaust guides. It holds heat and doesn't offer lubricity.
 This whole thing started about an F2 head if I remember correctly. Every one of those heads is/was/will be a problem. I have seen those with about .100 of play. And that is correct....    .100. I don't know how a valve stays in the head at that point.
 Honda warrantied these early on BUT was it a true fix? No because the replacement guides get smoked again. Why this whole exhaust guide wear happens has never been effectively explained to me. Perhaps the shortened valve length is a big contributor as the cam profile and different spring are certainly nothing radical. When I spoke about side loads on the valve I should have noted this is a real problem on rocker arm valvetrain. Possibly the shortened valve length exacerbates the problem. Shim/bucket arrangements place much, much less side thrust on the valve itself (like the Z1 and GS designs).
"Updated" guides have been mentioned.....I have a difficult time believing that even if a new part# was generated. As I mentioned.....warrantied guides get smoked too.
 So.....F2's eat guides....especially exhaust guides thanks to heat. I know that Kenny is working on a solution for this as he has seen it many, many times too. I have talked to him about it but am not at liberty to say much else.
 As for the coating....it is more of a surface treatment (meaning there is not much in way of surface build up)....I am not going to get into that either.

"Just to clarify...the guides were installed but a valve job was not done? The width of the 45 degree cut on the seat should be about .040 for the intake and about .060 for the exhaust. When you lap the valves the gray line on the valve should be around those values....it shouldn't cover the width of the valve face."

It was all done correctly, new valves, new guides, seats precision cut. Not sure where you are getting your information, or are you just assuming... ?
 

[74750k4]

I polished the coating off on one of my superflow valves in the area where it matters not - above the keeper groove - and i was not able to read any significant change in  the stem diameter using new micrometer. 

The difference was within measuring error.  That's why I went ahead with the valve installation.

I have another set of new CycleX SuperFlow valves sitting here. They look/measure essentially the same as the ones with 3000+ miles on them, with the exception of the face pitting. wondering if I should use them, or lose them...

[PeWe]

Very interesting discussion! This is when a technical forum becomes very interesting and educative.

I checked my valves today after work. The surface is very thin, almost like black surface on cam that will be scuffed off at bearing and lobe area.

It does not look like a surface that can flake off doing damage on guides or something else. I imagined surface like modern non stick frying pans with thicker coating.
Photo of my super flows with appr 2 hours of use revving in garage at top
 compared with 3 older I've got, unknown use except they look OK at seat angle plus one of my old used appr 15.000 miles

The scuff marks already visible after appr 2 hours use mostly 2-3000 rpm's. Revving up to 4-5000 when really warm.
Will look like the older ones, marks from valve seal and guide.....

My super flows going back in 

[74750k4]

good photos.

Mine with 3000+ miles show even less wear in the upper area of the stem. Mostly in the exposed chamber portion of the stem is where is see some mild wearing off of that very, very thin coating. I'm wondering if it's worth grinding the faces a bit to see if the pits are easily removed...

There was a ton of carbon in this head, and wondering if that's where the pitting came from. Not the mild coating on the stems.

[MRieck]

" I do not know who did the valve job but the valve face contact area looks very wide too....it should start at .060."

The valve faces were installed untouched, and compare perfectly in width to another full set of CycleX valves sitting here before me...



So the suggestion is slap it back together as is, and enjoy the ride???

I could go back to the stock springs, cam, and valves, at this point if that is what is being suggested. I don't like the guide wear I see though, and looks like those should be replaced...
with steel?

Not sure what to think.  Just want to ride!

Just to clarify...the guides were installed but a valve job was not done? The width of the 45 degree cut on the seat should be about .040 for the intake and about .060 for the exhaust. When you lap the valves the gray line on the valve should be around those values....it shouldn't cover the width of the valve face.
 Steel isn't a good material for valve guides especially exhaust guides. It holds heat and doesn't offer lubricity.
 This whole thing started about an F2 head if I remember correctly. Every one of those heads is/was/will be a problem. I have seen those with about .100 of play. And that is correct....    .100. I don't know how a valve stays in the head at that point.
 Honda warrantied these early on BUT was it a true fix? No because the replacement guides get smoked again. Why this whole exhaust guide wear happens has never been effectively explained to me. Perhaps the shortened valve length is a big contributor as the cam profile and different spring are certainly nothing radical. When I spoke about side loads on the valve I should have noted this is a real problem on rocker arm valvetrain. Possibly the shortened valve length exacerbates the problem. Shim/bucket arrangements place much, much less side thrust on the valve itself (like the Z1 and GS designs).
"Updated" guides have been mentioned.....I have a difficult time believing that even if a new part# was generated. As I mentioned.....warrantied guides get smoked too.
 So.....F2's eat guides....especially exhaust guides thanks to heat. I know that Kenny is working on a solution for this as he has seen it many, many times too. I have talked to him about it but am not at liberty to say much else.
 As for the coating....it is more of a surface treatment (meaning there is not much in way of surface build up)....I am not going to get into that either.

"Just to clarify...the guides were installed but a valve job was not done? The width of the 45 degree cut on the seat should be about .040 for the intake and about .060 for the exhaust. When you lap the valves the gray line on the valve should be around those values....it shouldn't cover the width of the valve face."

It was all done correctly, new valves, new guides, seats precision cut. Not sure where you are getting your information, or are you just assuming... ?

I was questioning whether a valve job was done...that's why a put a question mark there.
 You can grind the face....just watch the margin.

[74750k4]

Understood. Not sure yet how deep those pits are. I guess it can be done in stages to keep from widening the face too much...


So replace the guides again, or just let er' rip all the way to .100

[PeWe]

Another photo.

[SF]

Interesting

[Bailgang]

OK so I'm starting to gain a bit more confidence in the cyclex valves I have but my concern now is the pitting on the seat face of 74750k4's valves. If the nitride coating is the culprit could I avoid this potential problem by simply removing the nitride coating from the seat face of the valves before installing?

I apologize for sounding paranoid but I'll be working on the cyl head of my F2 soon so any words of wisdom is helpful.

[Nic]

Well I confess to bandwagoning to some degree, at first Mark delivers a horror blow that in the beginning I was not fully worried about, worse than throwing sand in there, he really did make it seem like these valves were a nightmare, intended or not I'm not sure but I can read. From then I sheepishly decided not to worry as my bike goes perfectly with only 1800K, so far so good?
Then I see the pics of 74750k4 and now I'm worrying again. If I have to buy new valves, new guides, and pay for the machine shop to do the job I'll be up for another $500 so of course I'm worrying again.
I've been using ZDDP from the start as well as a lead additive in non ethanol fuel. I've ditched the 41 cam but still have the kibblewhite springs without the shims. If, when I pull the engine down in a couple of months I find the valves etc in good nick then I will be very happy, shake my head n wonder what all the hoo haa was about, but, if I was about to install these valves and I've just read all the guff on the other thread, I would not do it just to be sure. The only reason I swapped out the original valves was that the PO had the faces reground beyond their limits, I understand you're not supposed to regrind the original valves at all.
So panties in a knot or not, I feel justified in pushing the wagon just a tad seeing as I "may" have to fork out another $500 

[bytio]

I and others on the forum have had issues with the cyclex valves (F2) the nitrate coating comes away on the stems causing damage to the guide and the seats, mine after 2000 miles and another after 700 giving lots of oil consumption and smoking, I had to strip top end again then replace with ape valves and guides, all is good now

[74750k4]

I' just  did an inspection of the INT valve, seat, face, and X-axis deflection.

So after 3000+ miles...   the intake side seems ok. .0035" deflection in X axis. Valve seat is fine, valve face is fine, all good on the intake side. My best guess is all the carbon flowing out, did the damage on the exhaust side.

I am now examining the brand new CycleX valves. There is no coating on the valve face. That is not where the problem originates.

So do not grind the valve faces on new CycleX valves!  worst case for me is having to replace the exhaust guides/valves, and remove the valve shims or go back to stock springs and shim those.

The face on the new valve does seem really wide...  but it's the seat width that is more important, no???

[PeWe]

.....
So do not grind the valve faces on new CycleX valves!  worst case for me is having to replace the exhaust guides/valves, and remove the valve shims or go back to stock springs and shim those.

- The valves must be lapped to match the seats, right?
I cannot see how these valves should be able to cause damaged guides. The coating is very thin, valve work without as I have understood by reading here.

Picture of the valve names and common reasons for problems
http://recoveryvehicles.tpub.com/TM-5-4240-501-14P/css/TM-5-4240-501-14P_277.htm

I have already bad conscience for my guide EX 4. The guide is not good after bent valve. Radial play  (in/out chamber center-EX) is about 0.1mm with valve 10mm out, less the other directions. This Seat had rust pores needed some lapping and Seat must be fixed as well..... I have had thoughts of fix that next season... maybe better with a complete head, more port job....$$$$