Close up study of a chain during drag race

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I suddenly feel safer with a shaft drive bike!
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I wonder if anyone else found themselves giggling at this.... that was awesome!

 
That is impressive. Gives me a better understanding of why they cost so damn much now that I've seen the abuse they have to be able to take.

 
That was pretty much what I expected to see. Would be even cooler to look at in high speed / slow mo.

That is (obviously) the slack side of the chain at the bottom. That lower stretch isn't really doing anything. All the work is being done up on top. Plus, during acceleration when the bike squats in the rear that slackens the chain even more.

Those alloy buzz saw rear sprockets are all the rage these days. The bottom of the teeth are undercut to allow spooge to be squeezed out and flung away. The trailing (and to a lesser extent leading) edges of the teeth are the only parts that bear any load. They don't last very long but they are much lighter. I still greatly prefer steel sprockets.

 
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On a little different note, did you notice that the front tire was lofting in the air almost all the way down the quarter mile? Good grief.

Gary

darksider #44

 
That was pretty much what I expected to see. Would be even cooler to look at in high speed / slow mo.
That is (obviously) the slack side of the chain at the bottom. That lower stretch isn't really doing anything. All the work is being done up on top. Plus, during acceleration when the bike squats in the rear that slackens the chain even more.

Those alloy buzz saw rear sprockets are all the rage these days. The bottom of the teeth are undercut to allow spooge to be squeezed out and flung away. The trailing (and to a lesser extent leading) edges of the teeth are the only parts that bear any load. They don't last very long but they are much lighter. I still greatly prefer steel sprockets.
I my road race days in the 90's we used hard anodized aluminum sprockets because it was unsprung weight and any weight on the rear wheel affect how fast the engine could rev. They were cheap to, about $50 apiece then. We used to change them, and the front sprocket to get the correct gear ratio for the track we were at. The front was also aluminum. It was surprising how long they lasted before you had to replace one.

 
I'm a huge drag race fan, as the OP will testify (we've visited a race or two together). What impressed me about this was the suspension travel on that bike. I had no idea how much the chassis moved during the run.

When I think about the unmitigated tornado of fury that is going on inside of a motorcycle engine (or any engine FTM) when running, it's no wonder that the whole thing doesn't disintegrate itself in less than 1 second.

 
Along these same lines of looking closely at something, here's a high speed camera video in real time of what a Bass String is doing when played. Looks a lot like what that chain was doing in the first video.



It's a stoboscopic effect caused by having each frame of the video composed of a very short time slice.

 
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Hard acceleration creates similar reactions with everything. Objects at rest want to stay at rest and will react when moved. Watch the arrow when released, this effect is worst with a hand release and gets a little better with a bow release. How the heck do archers hit anything?



The arrows look like swimming fish.



 
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