When talking about gear ratios, do you specify the smaller or larger gear
first?

Two meshed gears have a gear ratio of 3:1 Every time the larger gear
turns once, the smaller gear will turn?

a) 1/3 of the time b) 1 time c) 3 times

don wrote:
drive:driven so as to indicate a reduction or an overdrive.

"Pete C." <aux3.DOH.4 (AT) snet (DOT) net> wrote

Gear ratio is driven: drive.....41 teeth on ring gear: 10 teeth on pinion is
4.10:1 ratio.

don wrote:
A - the drive gear turns 3 times to turn the driven gear 1 time


The ratio is expressed as Drive gear : Driven gear.

4.10:1
means the drive gear turns 4.1 times to turn the driven gear 1 time
This is an under drive ratio

1:4
means that the drive gear turn 1 time and the driven gear turns 4 times
This would be an over driven ratio.


--
Steve W.
Near Cooperstown, New York

Augustus wrote:
No, it's drive:driven as in the 4.10 revolutions of the pinion *drive*
gear to the 1 revolution of the ring *driven* gear in your example.

If the large gear turns once, the smaller gear will turn three times.

3 to 1 means three times the teeth on the big gear as the small gear. Or the
large gear has a root circle three times as large as the small gear. In a
rear axle the ratio is turns of the drive shaft to turns of the tire. 3:1,
three turns of the drive shaft to one turn of the tire.

Al