Tech: Film of 4 stroke valve train at High RPM

stillwelding
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stillwelding
Edited Date/Time 1/26/2012 12:06am
It's a BMW at 14,200 RPM. The action doesn't really start until after the 1:00 minute mark. Damn! No wonder these things cost so much to re-build when things go POP

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scotttydog 2/18/2010 1:16am
2/18/2010 1:16am
Oh is that why those 4 stroke guys are "always checking" their hi tec poppet valve clearances?

That was painful to watch!
Motoxtombo
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Motoxtombo 2/18/2010 4:06am
2/18/2010 4:06am
Wow,Cool,Video,Its amazing how much the valve springs and retainers spin around.

The Shop

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Rupert X
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Rupert X 2/18/2010 5:37am
2/18/2010 5:37am


Yummy. I'm one of those guys that still really don't believe that machines really work.

Yet they do. It's magic.

Fascinating when you see the insides.

Internal combustion engines are, to me, like underwater-welding, even though I've

seen it, I still don't believe it.

jtomasik
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jtomasik 2/18/2010 5:46am
2/18/2010 5:46am
Now just think about the piston reciprocating in its cylinder. Don't forget, the crank's really the thing that's going 14,200 rpm, not the valve train. The valves are 1/2 that rate.

Remember the Honda oval piston bike? Didn't it operate at about 20,000 rpm? I think they ended up cranking that back because of issues, but I could be wrong. Wouldn't be surprising, though.
Racer92
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Racer92 2/18/2010 5:50am
2/18/2010 5:50am
What a waste, all those unnecessary moving parts.
2TYam27
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2TYam27 2/18/2010 6:00am
2/18/2010 6:00am
WOW! I wonder if the valves needed adjusting after that.
Rupert X
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Rupert X 2/18/2010 6:03am
2/18/2010 6:03am
jtomasik wrote:
Now just think about the piston reciprocating in its cylinder. Don't forget, the crank's really the thing that's going 14,200 rpm, not the valve train. The...
Now just think about the piston reciprocating in its cylinder. Don't forget, the crank's really the thing that's going 14,200 rpm, not the valve train. The valves are 1/2 that rate.

Remember the Honda oval piston bike? Didn't it operate at about 20,000 rpm? I think they ended up cranking that back because of issues, but I could be wrong. Wouldn't be surprising, though.


Yeah, I think that HONDA also had a 125 six banger that did 17,000 RPM....?
SteveS
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SteveS 2/18/2010 6:05am
2/18/2010 6:05am
Interesting to watch the oil smoking away to oblivion.
mxrose3
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mxrose3 2/18/2010 6:44am
2/18/2010 6:44am
serious valve-float there.
Big Lenny
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Big Lenny 2/18/2010 8:24am
2/18/2010 8:24am
Jeez , I was waiting for it to let loose, then I thought I smelled something burning...Huh
newmann
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newmann 2/18/2010 8:26am
2/18/2010 8:26am
Rotary valve? LOL. R6 Yamaha redlines at 17,500-20,000.
race
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race 2/18/2010 9:51am
2/18/2010 9:51am
The terms crude and primitive come to mind.

What a colossal joke that in this day and age such an archaic design is still in use.



Pit Row

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Blake
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Blake 2/18/2010 11:12am
2/18/2010 11:12am
Cox airplane engines 30-40K compared to

Racer92
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Racer92 2/18/2010 11:14am
2/18/2010 11:14am
race wrote:
The terms crude and primitive come to mind.

What a colossal joke that in this day and age such an archaic design is still in use.



Exactly. Its called the Otto Cycle and its antique farm machinery technology.

Engineering 101: Fewer moving parts = BETTER !
Roscoe33
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Roscoe33 2/18/2010 12:51pm
2/18/2010 12:51pm
race wrote:
The terms crude and primitive come to mind.

What a colossal joke that in this day and age such an archaic design is still in use.



so you lost me...

Don't keep it a secret...

I want to hear about the revolutionary system that you have to replace valves...
Pdub
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Pdub 2/18/2010 1:33pm
2/18/2010 1:33pm
race wrote:
The terms crude and primitive come to mind.

What a colossal joke that in this day and age such an archaic design is still in use.



The same thought occurred to me as well... after my mind was blown by the visuals, of course.

200,000 rpm electric motors with a single moving part are much higher tech.
JW381
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JW381 2/18/2010 1:53pm
2/18/2010 1:53pm
Wow. I sent that to a few people. Trying to spread the word.
Outsider
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Outsider 2/18/2010 1:56pm
2/18/2010 1:56pm
Cool video... how often does a 450 get spun that fast in the real world though?
scotttydog 2/18/2010 2:21pm
2/18/2010 2:21pm
Outsider wrote:
Cool video... how often does a 450 get spun that fast in the real world though?
Cool video... how often does a 450 get spun that fast in the real world though?
maybe if your heavy with your down shifts?
anyhow 450 valves and spring are bigger and have more mass so you cant turn them over as fast,

its all speed vs weight .
Rooster
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Rooster 2/18/2010 3:09pm
2/18/2010 3:09pm
Try roadracing one.

I'll take my supermoto out and embarrass the porkbike guys from time to time. Even on a smaller course I'm hitting the rev limiter 5-8 times a lap if it's geared right.
CASH476
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CASH476 2/18/2010 3:48pm
2/18/2010 3:48pm Edited Date/Time 2/18/2010 3:55pm
race wrote:
The terms crude and primitive come to mind.

What a colossal joke that in this day and age such an archaic design is still in use.



Roscoe33 wrote:
so you lost me...

Don't keep it a secret...

I want to hear about the revolutionary system that you have to replace valves...
Well said Roscoe.

Ps Cool video find stillwelding
CASH476
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CASH476 2/18/2010 3:54pm
2/18/2010 3:54pm Edited Date/Time 4/17/2016 8:51pm
Pdub wrote:
The same thought occurred to me as well... after my mind was blown by the visuals, of course. 200,000 rpm electric motors with a single moving...
The same thought occurred to me as well... after my mind was blown by the visuals, of course.

200,000 rpm electric motors with a single moving part are much higher tech.
I agree that it is mind blowing how these things work at such high revs/cycles.

I would disagree about the electric motors being much higher tech. Aren't these 200 000 rpm electric motors just a refined version of the motors built in the 1800s with better technology & materials, pretty much the same as modern 2 & 4 stroke engines?
Pdub
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Pdub 2/18/2010 4:22pm
2/18/2010 4:22pm
Pdub wrote:
The same thought occurred to me as well... after my mind was blown by the visuals, of course. 200,000 rpm electric motors with a single moving...
The same thought occurred to me as well... after my mind was blown by the visuals, of course.

200,000 rpm electric motors with a single moving part are much higher tech.
CASH476 wrote:
I agree that it is mind blowing how these things work at such high revs/cycles. I would disagree about the electric motors being much higher tech...
I agree that it is mind blowing how these things work at such high revs/cycles.

I would disagree about the electric motors being much higher tech. Aren't these 200 000 rpm electric motors just a refined version of the motors built in the 1800s with better technology & materials, pretty much the same as modern 2 & 4 stroke engines?
I'll grant that it's old tech (electromagnets, currents, etc), but IMO it's those same physics that make it "higher tech." Instead of relying on an expanding gas to move a piston to move a crank to move a series of valves, the properties of electromagnetics do all the work without anything actually touching anything, other than the brushes and bearings. And that just about reaches the limits of my comprehension on the subject!

So we're not talking about the age of the tech, but the relative efficientcy?

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