Author Topic: Buying Valves  (Read 3456 times)

0 Members and 1 Guest are viewing this topic.

Offline DanJ

  • Enthusiast
  • **
  • Posts: 142
Buying Valves
« on: November 20, 2013, 09:02:34 AM »
I'm going to need new valves for my 73 K-3 are valves from Cycle-X a good choice?

Thanks

Dan

Offline DanJ

  • Enthusiast
  • **
  • Posts: 142
Re: Buying Valves
« Reply #1 on: November 22, 2013, 05:01:03 AM »
Ok does any one have any suggestions on which valves to buy?

Offline 70CB750

  • Labor omnia vincit improbus.
  • Really Old Timer ...
  • *******
  • Posts: 14,805
  • Northern Virginia
Re: Buying Valves
« Reply #2 on: November 22, 2013, 05:26:12 AM »
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 
Prokop
_______________
Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline HondaMan

  • Someone took this pic of me before I became a
  • Really Old Timer ...
  • *******
  • Posts: 13,882
  • ...not my choice, I was nicknamed...
    • Getting 'em Back on the Road
Re: Buying Valves
« Reply #3 on: November 22, 2013, 05:31:35 PM »
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.  :-\
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com

Offline flybox1

  • My wife thinks I'm a
  • Really Old Timer ...
  • *******
  • Posts: 14,301
Re: Buying Valves
« Reply #4 on: November 22, 2013, 05:46:38 PM »
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.
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline HondaMan

  • Someone took this pic of me before I became a
  • Really Old Timer ...
  • *******
  • Posts: 13,882
  • ...not my choice, I was nicknamed...
    • Getting 'em Back on the Road
Re: Buying Valves
« Reply #5 on: November 22, 2013, 08:35:44 PM »
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. :(
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com

Offline 70CB750

  • Labor omnia vincit improbus.
  • Really Old Timer ...
  • *******
  • Posts: 14,805
  • Northern Virginia
Re: Buying Valves
« Reply #6 on: November 23, 2013, 01:48:46 AM »
Thanks, Mark  ;D

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?
Prokop
_______________
Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline PeWe

  • Really Old Timer ...
  • *******
  • Posts: 15,595
  • Bike almost back to the 70's 2015
Re: Buying Valves
« Reply #7 on: November 23, 2013, 02:27:24 AM »
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? ???
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline DanJ

  • Enthusiast
  • **
  • Posts: 142
Re: Buying Valves
« Reply #8 on: November 23, 2013, 04:08:51 AM »
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

Offline 70CB750

  • Labor omnia vincit improbus.
  • Really Old Timer ...
  • *******
  • Posts: 14,805
  • Northern Virginia
Re: Buying Valves
« Reply #9 on: November 23, 2013, 04:11:33 AM »
Truth be told I noticed the coating coming of on the stem after short test lapping of the seat. :(
« Last Edit: November 23, 2013, 06:40:21 AM by 70CB750 »
Prokop
_______________
Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline 70CB750

  • Labor omnia vincit improbus.
  • Really Old Timer ...
  • *******
  • Posts: 14,805
  • Northern Virginia
Re: Buying Valves
« Reply #10 on: November 23, 2013, 08:31:09 AM »


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.
Prokop
_______________
Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline Big Jay

  • Expert
  • ****
  • Posts: 1,252
    • CBRzone
Re: Buying Valves
« Reply #11 on: November 23, 2013, 04:00:40 PM »
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.


Offline 70CB750

  • Labor omnia vincit improbus.
  • Really Old Timer ...
  • *******
  • Posts: 14,805
  • Northern Virginia
Re: Buying Valves
« Reply #12 on: November 23, 2013, 04:54:44 PM »
Nice pitch, but I am building F3 engine.
Prokop
_______________
Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline tlbranth

  • Master
  • *****
  • Posts: 1,659
Re: Buying Valves
« Reply #13 on: November 23, 2013, 05:42:10 PM »
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?
Don't own a Vanagon
Don't work at Boeing
Life is good

1970 CB750 K0
1975 GL1000
1999 GL1500
2002 VT750-CDA ACE - Momma's bike
Terry

Offline HondaMan

  • Someone took this pic of me before I became a
  • Really Old Timer ...
  • *******
  • Posts: 13,882
  • ...not my choice, I was nicknamed...
    • Getting 'em Back on the Road
Re: Buying Valves
« Reply #14 on: November 23, 2013, 09:59:59 PM »
Thanks, Mark  ;D

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. :(
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com

Offline 70CB750

  • Labor omnia vincit improbus.
  • Really Old Timer ...
  • *******
  • Posts: 14,805
  • Northern Virginia
Re: Buying Valves
« Reply #15 on: November 24, 2013, 02:44:37 AM »
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?  :D
Prokop
_______________
Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline kmb69

  • Master
  • *****
  • Posts: 2,041
Re: Buying Valves
« Reply #16 on: November 24, 2013, 06:00:59 AM »
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.


Offline tlbranth

  • Master
  • *****
  • Posts: 1,659
Re: Buying Valves
« Reply #17 on: November 24, 2013, 09:20:36 AM »
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
Don't own a Vanagon
Don't work at Boeing
Life is good

1970 CB750 K0
1975 GL1000
1999 GL1500
2002 VT750-CDA ACE - Momma's bike
Terry

Offline timbo750

  • Expert
  • ****
  • Posts: 759
Re: Buying Valves
« Reply #18 on: November 25, 2013, 11:57:27 AM »
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?

Offline lrutt

  • Expert
  • ****
  • Posts: 916
Re: Buying Valves
« Reply #19 on: November 25, 2013, 01:26:13 PM »
what about Kibblewhites?? I thought they were like the defacto standard to go with?? or do they not make SOHC valves?
06 Harley Sporster 1200C, 06 Triumph Scrambler, 01 Ducati Chromo 900, 01 Honda XR650L, 94 Harley Heritage, 88 Honda Hawk GT, 84 Yamaha Virago 1000, 78 Honda 750K w/sidecar, 77 Moto Guzzi Lemans 850, 76 Honda CB750K, 73 Norton 850, 73 Honda Z50, 70 & 65 Honda Trail 90, 70 & 71 Triumph 650s, 65 Honda 305 Dream, 81 Honda 70 Passport, 70 Suzuki T250II, 71 Yamaha 360 RT1B, 77 BMW R75/7, 75 Honda CB550K, 70 Honda CT70

Offline Jerry Rxman Griffin aka MuthaF'er

  • This MuthaF'er is getting to be a
  • Really Old Timer ...
  • *******
  • Posts: 14,920
  • Bought her new 4/75
Re: Buying Valves
« Reply #20 on: November 25, 2013, 02:36:02 PM »
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.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline timbo750

  • Expert
  • ****
  • Posts: 759
Re: Buying Valves
« Reply #21 on: November 25, 2013, 03:05:19 PM »
I was under the impression that Kibblewhite made the valves for cycleX but I could be wrong here.

Offline MRieck

  • Really Old Timer ...
  • *******
  • Posts: 10,565
  • Big ideas....
Re: Buying Valves
« Reply #22 on: January 01, 2014, 07:18:03 AM »
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
Owner of the "Million Dollar CB"

Offline Maraakate

  • Hot Shot
  • ***
  • Posts: 316
Re: Buying Valves
« Reply #23 on: August 12, 2023, 05:32:08 AM »
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

Quote
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.
1977 CB550K
1979 CM400A

Offline rotortiller

  • Expert
  • ****
  • Posts: 856
Re: Buying Valves
« Reply #24 on: August 12, 2023, 07:43:33 AM »
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.

Offline Don R

  • My Sandcast is a
  • Really Old Timer ...
  • *******
  • Posts: 19,968
  • Saver of unloved motorcycles.
Re: Buying Valves
« Reply #25 on: August 12, 2023, 08:12:42 AM »
 I got new F2 valves from Dynoman, everyone else was sold out at the time. I believe both intake and exhaust are kibblewhite even though one was branded from Dynoman and less expensive. I have not done anything with the head yet.
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.

Offline Nurse Julie

  • Hot Shot
  • ***
  • Posts: 353
Re: Buying Valves
« Reply #26 on: August 13, 2023, 12:33:38 PM »
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.  :-\
Is that black coating a type of Teflon which shouldn't be removed or do the CycleX ones have a different coating?
« Last Edit: August 13, 2023, 12:35:21 PM by Nurse Julie »
Trust me I'm a Nurse, I promise it won't hurt....much

Offline Tracksnblades1

  • My Son was a collegiate competition Trap, Skeet, and sporting Clay
  • Master
  • *****
  • Posts: 1,858
Re: Buying Valves
« Reply #27 on: August 13, 2023, 05:27:28 PM »
What’s going on ?

I’ve got a MRieck’s Stage 4 cylinder head (with 5mm Kibbles) for his 1005 billet block on the shelves in the basement…

Are we talking black diamonds or what…?

🤔🤔
Age Quod Agis

Offline Tracksnblades1

  • My Son was a collegiate competition Trap, Skeet, and sporting Clay
  • Master
  • *****
  • Posts: 1,858
Re: Buying Valves
« Reply #28 on: August 13, 2023, 05:33:29 PM »
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? ???

PeWe,

Are we talking about the kibbles and the beehive set or the Cx Superflows..?
« Last Edit: August 13, 2023, 05:42:51 PM by Tracksnblades1 »
Age Quod Agis

Offline HondaMan

  • Someone took this pic of me before I became a
  • Really Old Timer ...
  • *******
  • Posts: 13,882
  • ...not my choice, I was nicknamed...
    • Getting 'em Back on the Road
Re: Buying Valves
« Reply #29 on: September 02, 2023, 09:37:01 PM »
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

Quote
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.

Yeah, Ken actually called me one day at my old job to ream me out for this post.
But, the truth is, I relayed my experience verbatim as above. It cost me a small fortune to rebuild that guy's head with new guides, seals, etc., and I lost every cent in the transaction. I told Ken the same thing when he called me: I had installed them with the clearance info he provided me with the valves. The customer was competent with his engine reassembly work. That's about all I can add to it, except Ken has been mad at me ever since, I think. He said the machine shop must have done something wrong with the clearance numbers, but I checked them myself before reassembly (the first time) and found them to be the same ones Ken gave me: this machine shop has installed a lot of coated valves in racing engines, too, so they had experience - and that was why I let THEM do it instead of me.

In the end, I don't know what happened to cause the guides to become so loose and have their odd larger top-and-bottom clearances after relatively few miles: it has never happened to me before nor since, but that was the only time I ever used "coated" valves. I do know that polishing off the remaining coating from the stems made for a good engine afterward, which ran for over a year and was sold in that cafe' bike for north of $10 grand after that.
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com