Topic: CycleX SuperFlow Valves

[MRieck]

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???

So your original valves had the valve face coated? I have gotten those valves in the past and ground them to remove the coating before installing them. I haven't seen any of these valves with coated faces in quite a while.
 I see where people are talking about the coating and the valve seat.....maybe I missed that part (no...I went back and reread the original thread). It made no sense to me that a coating on the stem could be involved with the seat.
 I said before Kibblewhite valves show the same wear pattern.
 Like I said before....the F2 heads are bad in regard to exhaust guide/valve wear. This is a problem created by Honda (and they acknowledged it by performing warrenty work). I would #$%* hard and long about their involvement as well. I know Kenny is working on a better set up involving different guide material etc.
 I recommend grinding the valve faces if they are coated....that is something I did as a matter of judgement. The only valve I would put in with a coated face is a Ti valve. You do not lap them either.

[74750k4]

If you read carefully...

There is NO coating on the face of the valve!!! Original installation of CycleX valves NO COATING on valve face.
Set of brand new CycleX valves in front of me... NO COATING on valve face.

Never seen a coating on the VALVE FACE. Ken at CycleX told me not to LAP them in.

[MRieck]

If you read carefully...

There is NO coating on the face of the valve!!! Original installation of CycleX valves NO COATING on valve face.
Set of brand new CycleX valves in front of me... NO COATING on valve face.

Never seen a coating on the VALVE FACE. Ken at CycleX told me not to LAP them in.

OK....OK....calm down....there were different people chiming in.
   Like I said....I have seen surface treatment on the valve face of some CycleX valves. It was a while ago but regardless it might explain this talk of "ruined seats" and having to sink a valve .040 (though I have seen rusted out seats require much less) .
 I have seen valve faces coated by the old HPC, Swain Tech and Calico too. I was instructed not to touch them as they had a distinct purpose. As I said...Ti too.
 I lap those valves to check the seat and the valve face....my personal preference. I have lapped seats equipped with Ti valves using the ground OLD valve to check the seat concentricity.
 Anyway...Good luck....at this point no matter what you put in there you will unfortunately have problems with guide wear. Hopefully these new guides can help in that department. In the end it is a manufactures mistake.

[74750k4]

Yeah, I have some earlier heads here that are not 392...   300 series...   wishing now i had used those as a platform. I was thinking it was the guide material, not the steeper angle that caused the problems.

[Jerry Rxman Griffin aka MuthaF'er]

So where did the 392 vs 300 come in or did I misinterpret?

I didn't think there was an angle difference in these 392 and 300 heads, just the shape of the chamber. I thought the angle came into play on the F2/F3 head ONLY??!!

[PeWe]

Maybe OT....
This interesting thread cost me some $$$$
I had to check my inlet valves too, OEM F2 inlet valves used as oversized valves in my K6 head. They have all deep dimples where the adjuster hits the valve. I had to press the valves thru the guides to take them out. A little bit more and I had to grind them to take them out.  This has happened before back in the days too. I thought somebody had grinded the stem and hardening off. This time nothing like that. Maybe 20.000 km's use.
- Is dimpled valves a common issue? Too soft metal used, bad hardening process?

Lets see new ex guides, new inlet valves.... maybe new inlet guides too. Lets hope my ex4 seat will pass my Local tuner still in business that ported the head back in 1983....

[70CB750]

That's what valves on the F head looked like when I took it apart, I had to grind few on the exhaust side to get them out.

[PeWe]

Breaking news!
Now back from my local tuner were I left the head. I thought new guides. Wrong! Guides were all OK.

BUT, the 28 mm super flow valves used on exhaust have all thinner stems compared with new Kibblewhite. He measured 0.03mm less than Kibblewhite or OEM. Maybe this is the issue with earlier guide worn, carbonized particles can enter due to more play.....? Or just my valves?

Verdict:
New EX valves ordered, Kibblewhite 28mm.  Super flow not to be used anymore
New F2 OEM inlet valves.
Cut an extra (30 degrees?) angle on all valves for earlier gas flow as they did back in the days
Cut all valve seats
Some cleaning
Check of spring heights when it can be too high pressure on the shorter F2 stems.

NOT new EX guides as I thought. I was worried to get something else than the old OEM steel stuff.

[MRieck]

So where did the 392 vs 300 come in or did I misinterpret?

I didn't think there was an angle difference in these 392 and 300 heads, just the shape of the chamber. I thought the angle came into play on the F2/F3 head ONLY??!!

The valve angle is the same for all the 750 heads. Honda sunk the valves to get enough valve to valve clearance on the F2. This enlarged the chamber and required shorter OAL for the valves.

[74750k4]

The heads I used were stock off of a 78' K8 marked "392"  so not sure if, or how,  those are different than F2/F3. I understood the chambers were enlarged on these compared to earlier 300 series heads, and they use the 392 pistons as well.  Mistakenly thought the valve angles had changed too. Apparently not the case.

The guides I used do not extend out into the port area much at all. Mostly smooth, and even with the bore into the head. So the length of the guide may be a big contributing factor on the wear happening.

[Jerry Rxman Griffin aka MuthaF'er]

Has anyone cc'ed or know of the measurements on the 300 heads vs the 392 heads?

Keep in mind that the compression ratio of the 392 engines was advertised as 9.2:1 vs the 9.0:1 of the 300 engines. I have 2 sets of 392 labeled pistons that had different domes on them so I don't know how Honda claims that both the K8 and my F0 BOTH had 9.2:1?! They both have the same head however. Perhaps the 392 head cc's out at less than the 300 head?! The 300 head has the shrouding in it while the 392 head is more of a smooth 'hemi' style chamber.

Didn't the 300 engines use both style domed pistons too? The earlier K and the earlier F seemed to run better but we know cams also helped this.

F0 on the left K8 on the right



Side view for dome height




NOW BACK TO VALVES....................

[MRieck]

The heads I used were stock off of a 78' K8 marked "392"  so not sure if, or how,  those are different than F2/F3. I understood the chambers were enlarged on these compared to earlier 300 series heads, and they use the 392 pistons as well.  Mistakenly thought the valve angles had changed too. Apparently not the case.

The guides I used do not extend out into the port area much at all. Mostly smooth, and even with the bore into the head. So the length of the guide may be a big contributing factor on the wear happening.

  Try the Kibblewhite exhaust guides as they are the original OEM length (which are longer than the intake guides).

[70CB750]

So where did the 392 vs 300 come in or did I misinterpret?

The valve angle is the same for all the 750 heads. Honda sunk the valves to get enough valve to valve clearance on the F2. This enlarged the chamber and required shorter OAL for the valves.

In that case would different cam in F2 head help with valves longetivity?  I remember suggestion to use K6 cam in F head.

[74750k4]

Has anyone cc'ed or know of the measurements on the 300 heads vs the 392 heads?

Keep in mind that the compression ratio of the 392 engines was advertised as 9.2:1 vs the 9.0:1 of the 300 engines. I have 2 sets of 392 labeled pistons that had different domes on them so I don't know how Honda claims that both the K8 and my F0 BOTH had 9.2:1?! They both have the same head however. Perhaps the 392 head cc's out at less than the 300 head?! The 300 head has the shrouding in it while the 392 head is more of a smooth 'hemi' style chamber.

Didn't the 300 engines use both style domed pistons too? The earlier K and the earlier F seemed to run better but we know cams also helped this.

F0 on the left K8 on the right



Side view for dome height




NOW BACK TO VALVES....................

Those are my pistons on the right. did not know the other ones on the left had the same 392 designation, wow, that's confusing...

[74750k4]

The heads I used were stock off of a 78' K8 marked "392"  so not sure if, or how,  those are different than F2/F3. I understood the chambers were enlarged on these compared to earlier 300 series heads, and they use the 392 pistons as well.  Mistakenly thought the valve angles had changed too. Apparently not the case.

The guides I used do not extend out into the port area much at all. Mostly smooth, and even with the bore into the head. So the length of the guide may be a big contributing factor on the wear happening.

  Try the Kibblewhite exhaust guides as they are the original OEM length (which are longer than the intake guides).

good to know...   thanks. I think that should help.

[HondaMan]

Has anyone cc'ed or know of the measurements on the 300 heads vs the 392 heads?

Keep in mind that the compression ratio of the 392 engines was advertised as 9.2:1 vs the 9.0:1 of the 300 engines. I have 2 sets of 392 labeled pistons that had different domes on them so I don't know how Honda claims that both the K8 and my F0 BOTH had 9.2:1?! They both have the same head however. Perhaps the 392 head cc's out at less than the 300 head?! The 300 head has the shrouding in it while the 392 head is more of a smooth 'hemi' style chamber.

Didn't the 300 engines use both style domed pistons too? The earlier K and the earlier F seemed to run better but we know cams also helped this.

F0 on the left K8 on the right



Side view for dome height




NOW BACK TO VALVES....................

Those are my pistons on the right. did not know the other ones on the left had the same 392 designation, wow, that's confusing...

In the last 4 years, I have disassembled 3 K7 engines and 1 K8 engine, all virgin. The K8 had the piston(s) on the right with the "mini-dome", while the K7 engines all had the one on the left. I'll dig around, might still have those pistons in a box somewhere. They did not all have the '392' on them, either, some did, some did not. I'll try to find them so I can see which ones had the '392' on the wristpin recesses.

[74750k4]

Funny how these posts kind of drift in and out of topic...   anyway I was browsing Kibblewhite's new catalog pages http://www.kpmivalvetrain.com/pdf/2013_2014KPMICatalog_Hondaproducts.pdf  ,and noticed their valves look identical to the CycleX Super Flow valves.  Same coating, same finish on the valve face. Wonder who's making those valves? Wonder if anyone is complaining on Kibblewhite about them?

[74750k4]

I guess the topic can't be changed to include Kibblewhite, but it's looking like it should be...

[Nic]

Funny how these posts kind of drift in and out of topic...   anyway I was browsing Kibblewhite's new catalog pages http://www.kpmivalvetrain.com/pdf/2013_2014KPMICatalog_Hondaproducts.pdf  ,and noticed their valves look identical to the CycleX Super Flow valves.  Same coating, same finish on the valve face. Wonder who's making those valves? Wonder if anyone is complaining on Kibblewhite about them?

Yeah I saw them too n thought they looked the same.

[Jerry Rxman Griffin aka MuthaF'er]

Is it possible that CycleX is marketing the infamous KPMI Black Diamond valves that have been used for ages?! Have they suddenly become bad? The mystery continues.....

[KayOne]

Hope not. My set just went to the machine shop today. The look very much like the pics posted by PeWe.

[Jerry Rxman Griffin aka MuthaF'er]

I doubt we have to worry about KPMI Black Diamond valves... but you never know....

[Bailgang]

I don't have much choice because my original valves on my F2 are severely indented where the rocker arm make contact so the superflows are going in.

[Nic]

My engine is now blowing black smoke on first start up with 2500Ks on the rebuild so I'm thinking the guides and or seals are kaput now. Have engine out and will inspect shortly and post results. While I have the engine out it is getting cheap 836 pistons and new trans bearings, starter brushes and oil pump stopper valve n spring.
Putting Yamiya valves in this time.

[Retro Rocket]

Black smoke is usually fuel related, blue smoke is oil....   Guides and seals should last way longer than 2500, even cheap ones...