About time for the spintron

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Its like watching a hummingbird flap its wings in slow motion. I still can't get over how much the springs harmonic after the valve closes. 8)
Cheers,
Thomas
CNN
 
The research been done on push rod valve train priority to find push rod stiffness matters rather more than their mass or mass in general on the cam side of rockers. Maney sells steel tubes cut to order. Maney says he trys to limit his stock stroke full race 920's to 7200. I go to races to see the crashes and want to see spintron resolution of a valve hanging so piston bashes into it and rod cap bolts pulling apart then steel caps chewed up like gum in a flash, chips of exploding metal of broken lifter jamming the cam to sieze engine piling up behind.

Retainer failure let down
https://www.youtube.com/watch?v=Iqq-RNDea9U

old school finned engine 9grand failure
https://www.youtube.com/watch?v=a-fs8CFnZ_g
 
hobot said:
......... I go to races to see the crashes and want to see spintron resolution of a valve hanging so piston bashes into it and rod cap bolts pulling apart then steel caps chewed up like gum in a flash, chips of exploding metal of broken lifter jamming the cam to sieze engine piling up behind.
That's messed up Steve, maybe you could have the cameras rolling as you, rev the snot out of the bike you call peel, while you run it head long into a big oak tree......
 
Now this is impressive.

This is with no change other than the switch to conical valve springs with Ti retainers. They are set at about 5 lbs less seat pressure than the old springs.

7266 rpm at 9000 fps.

[video]https://youtu.be/nueQO1YnJ1I[/video]

No valve bounce anymore. :D Jim
 
Here is the conical spring view at 7266 rpm.
It still wiggles.

[video]https://youtu.be/O4NOvFyRZXI[/video]
 
Here is a view of the pushrods at 7266 rpm. They look pretty happy to me. Jim

[video]https://youtu.be/U0vKfMZqQQk[/video]
 
That big intake valve is behaving. Less mass at the valve collar make a big difference and the spring even thou its bouncing is doing a better job.
Cheers,
Thomas
CNN
 
CanukNortonNut said:
That big intake valve is behaving. Less mass at the valve collar make a big difference and the spring even thou its bouncing is doing a better job.
Cheers,
Thomas
CNN

Yep, I was pleasantly surprised at the difference.
Now we will see what happens when I add a little bigger cam to the mix. Jim
 
swooshdave said:
Can you post more about the camera setup? Hardware and software, etc. Thanks.

Dave,
The camera is a Kodak Ectapro 4540 from about 1998. It is just black and white but it has the ability to shoot up to 40500 FPS. I use a c-mount 75mm zoom TV lens at f1.8. I would like to find a little faster lens for the higher record rates.

It records on RAM and originally communicated with a PC using a scuzzy interface. [very slowly- like 50 minutes to copy one burst]

I now use the composite video out and a video capture card to get the video into my PC. At first I was using an old Ospey Viewcast card in a PCI slot but that was pretty painful.

A couple days ago I picked up a Startech USB capture cable on Amazon that works pretty slick and doesn't drop half the frames like the older card did. It also get's along with Windows movie maker so that makes it easy. Jim
 
Since the PW3 cam I had wouldn't fit through my quick change hole because of the wide lobes I decided to go all out.
Here is a Norris D+ grind with the street conical springs. Everything else is stock.
7266 rpm 18000 fps.

Not good. The valve obviously hits the seat after the closing ramp and bounces pretty seriously.

[video]https://youtu.be/2O-ZyvYk73M[/video]

Next I will install some lightened rockers and see how much that helps. Jim
 
I for one would be realy interested to see a PW3 with the lightened rockers better springs and titanium retainers even though it would be a lot more work for you to set up the test. Mostly because that is the setup i have. But when turning the engine over you can feel how slowly and gently the valve is put back on the seat. There are a good few degrees of crank movement as the last few thou of lift come off the valve.
 
comnoz said:
Since the PW3 cam I had wouldn't fit through my quick change hole because of the wide lobes I decided to go all out.
Here is a Norris D+ grind with the street conical springs. Everything else is stock.
7266 rpm 18000 fps.

Not good. The valve obviously hits the seat after the closing ramp and bounces pretty seriously.

[video]https://youtu.be/2O-ZyvYk73M[/video]

Next I will install some lightened rockers and see how much that helps. Jim

Jim, is this the same valve that showed flexing/distortion in the stem? If so what do you aquaint this to. Possibly friction from the tappet to valve tip? Bad guide? If there was less friction in this relationship, if this is the case, might this bounce be less pronounced?
 
pete.v said:
comnoz said:
Since the PW3 cam I had wouldn't fit through my quick change hole because of the wide lobes I decided to go all out.
Here is a Norris D+ grind with the street conical springs. Everything else is stock.
7266 rpm 18000 fps.

Not good. The valve obviously hits the seat after the closing ramp and bounces pretty seriously.

[video]https://youtu.be/2O-ZyvYk73M[/video]

Next I will install some lightened rockers and see how much that helps. Jim

Jim, is this the same valve that showed flexing/distortion in the stem? If so what do you aquaint this to. Possibly friction from the tappet to valve tip? Bad guide? If there was less friction in this relationship, if this is the case, might this bounce be less pronounced?

Pete,
They all show flex in the valve stem. It is due partially to the rocker arm friction but I have seen the same flex on engines with roller rocker arm tips.
The valve bounce is due to the valve closing hard and fast -causing it to bounce.
The means either the closing ramp is very harsh -like the Norris D+ or the valve is not following the cam lobe on the closing side of the lobe so it misses the ramp altogether. Jim
 
toppy said:
I for one would be realy interested to see a PW3 with the lightened rockers better springs and titanium retainers even though it would be a lot more work for you to set up the test. Mostly because that is the setup i have. But when turning the engine over you can feel how slowly and gently the valve is put back on the seat. There are a good few degrees of crank movement as the last few thou of lift come off the valve.

I will be installing the PW3. I just need to do a little machine work on my engine case to get it through the quick change cam hole. I am sure it will be much easier on the valve train than the Norris D+. Jim
 
Gosh Norris D opens valves alot while barely missing but don't seem very significant seat bounce to me so have to take your word for it as applies directly to Peel's deal with smaller stem valves and lighted lifters & rockers.

About time for the spintron
 
Here is a spin with lightened rocker arms. I couldn't see much difference.

[video]https://youtu.be/hG37CigLpiQ[/video]

Here is a spin with the conical race spec springs installed. Slightly better but there is still a pronounced bounce.

[video]https://youtu.be/hG37CigLpiQ[/video]

So I installed the old standard -Kibblewhite race springs with aluminum retainers shimmed to 130lbs of seat pressure.

[video]http://youtu.be/HS6wSXSFs5w[/video]

Definitely not as good as either conical spring - it looks like the D+ has a reputation for being tough on valve trains for a reason. Jim
 
Jim,

Is this an original Norris cam or a Megacycle version. The reason I ask is that I recall reading about Megacycle reworking the profile primarily in the ramps.
 
comnoz said:
Here is a spin with lightened rocker arms. I couldn't see much difference.

[video]https://youtu.be/hG37CigLpiQ[/video]

Here is a spin with the conical race spec springs installed. Slightly better but there is still a pronounced bounce.

[video]https://youtu.be/hG37CigLpiQ[/video]

So I installed the old standard -Kibblewhite race springs with aluminum retainers shimmed to 130lbs of seat pressure.

[video]http://youtu.be/HS6wSXSFs5w[/video]

Definitely not as good as either conical spring - it looks like the D+ has a reputation for being tough on valve trains for a reason. Jim

Jim,
You had me excited a couple post back with the stock cam changing to the conical race springs. I didn't catch the diameter of the current valve stems and I am sorry if you have already stated this. There is a asymmetrical in a box there that I would love to see how it reacts to the current set up with the conical springs to see if the 17A grind has the same result as the D+ or if the radical closer helps the valve float.

Paul
 
Dances with Shrapnel said:
Jim,

Is this an original Norris cam or a Megacycle version. The reason I ask is that I recall reading about Megacycle reworking the profile primarily in the ramps.

This is an original Norris D+. From what I see it could use some work on the ramps.

I used the valve clearance specs from the Megacycle site. I wonder if the original clearance specs were the same.
Magacycle says .015. Jim
 
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