About bicycle sprockets
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Does anyone know why the big sprocket on the bicycles we use every day is oval?
It's a labor-saving machine, but I didn't notice that the ellipse must be worn.
What you bought is a fake and shoddy product.
Oval sprocket... How much does it cost to make a set of such a transmission sprocket? It must be more than a bicycle.
Did you buy an oval sprocket? It’s as if everyone has never seen a bicycle. :lol :lol
What I'm talking about is that the front sprocket is slightly oval. I've seen a new bicycle with hand-operated pedals and the bicycle chain has a phenomenon of one step and one step every cycle. Is the bicycle a defective product?
The poster added that the performance of the oval sprocket is "the phenomenon of one chain and one speed in the cycle of the bicycle chain". I know the cause of the "phenomenon of one chain and one speed in the cycle of the bicycle chain". The bicycle sprocket is absolutely round because it is a stamped part. There are two reasons for the "bicycle chain cycle phenomenon": First, the clearance between the bicycle's central axis is too large, and the central axis swings when the two feet are stepped hard. ； The second is that the sprocket is deformed and the peripheral tooth profile is not on the same plane, but the tension and chi caused by this reason are small. If you want to verify, just tighten the bottom bracket clearance and you can judge.
I think what the original poster said is also inspiring. The oval sprocket might actually be of use value, because when a person pedals a bicycle, the force acting on the sprocket is changing. When the pedal is in a horizontal position, the torque is maximum. At this time, if the long axis of the sprocket is aligned with this position, the speed of the bicycle may be increased. However, due to the high cost, it may only be used as competition cars for athletes.
I have never seen an oval sprocket. You may have read it wrong. The chain is originally loose, and the periodic changes in pedaling force while riding give you an illusion.