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- Aug 8, 2005
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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
Cheers,
Thomas
CNN
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......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.
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
swooshdave said:Can you post more about the camera setup? Hardware and software, etc. Thanks.
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
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?
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.
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
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.