Take two different, but effectively the same gear ratios.
To make it easy I'll say 46t chainring with a 23t rear cog and a 50t chainring with a 25t rear cog
Both are a 2:1 ratio
Which would be easier to pedal? Would the size of the 50t ring give you a mechanical advantage over the 46t ring?
Exactlty the same.Yes but its is negated by the larger rear sprocket.
You could have 16/8 or 100/50,makes no odds.
Unless you start changing crank length.....
As above; the gearing is the same (in both cases, you go forward two wheel turns for each turn of the pedals).
However, the larger front/back pair is generally better - more teeth engaged, less wear, and the chain tension is lower.
So a larger chainring does give you a mechanical advantage?
Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. Ideally, the device preserves the input power and simply trades off forces against movement to obtain a desired amplification in the output force.
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the gear ratio is the same - the two larger sprockets would give you slightly less mechanical losses I think. I doubt you would notice
I shouldnt have mentioned ratios n that really. I should have just said "does a 50t chainring give you more leverage thatn a 46t?"
just something to add, the larger sizes should spread the load across the sprockets and chainrings better reducing wear, but it would weigh more.
No, the 50t gives you less leverage because it's closer in length to that of the lever pushing it (crank one side of the pivot point, chainring the other side of it). The 25t gets you that leverage back because it's closer in diameter to the wheel than the 23t is.