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Which is a higher or lower gear in a vehicle?

My bro and I have been arguing this for hours and can’t find any hard proof online. I tell him that first gear is the highest gear in a vehicle “or bike”. He is convinced that 2nd 3rd and so on are the higher gears. He insists that based on internet searches like up or down shifting prove that he is right. Please answer and clarify this in detail if you would. Thank you!!

The problem here is one of definition.

1st gear is a higher numerical gear (higher ratio of rotational speed reduction), but we normally think of lower numerical gears as producing higher speeds.

Sorry, he’s right. When you talk about a gear, you’re talking about the gear ratio, which is the number of rotations going into a gear divided by the number coming out. In a lower gear, the engine needs to rotate several times per rotation of the driveshaft (which eventually transmits the power to the drive wheels) and so the gear ratio will be a fraction. On typical 5-speed transmissions, 4th gear is usually “direct drive” with a gear ratio of one-- in other words the same number of rotations going in as going out-- and 5th will be overdrive, which means that the ratio is more than one-- more revolutions coming out than going in.

The way me and my fellow mechanics have always talked, higher gear is 3rd, 4th, and 5th. When talking gear ratios, we use taller or shorter. 1st gear is the tallest, but lowest, and 5th gear is the highest, but shortest. Taller and shorter are also used to describe gear ratios in differentials.

I vote with Busted Knuckles - that’s the (confusing) lingo I’m familiar with.

In transmissions the gear that gives you the greatest mechanical “help” is called your low gear 1st gear (unless you want to include reverse)

In rear ends a differential ratio that gives you the greatest mechanical “help” has a higher neumerical number than a ratio that gives you less help. A 4.11 gear ratio gives you more “help” than a 2.73, a car with a 4.11 rear diff.ratio is said to be lower geared than a car with a 2.73 ratio

In the good old days before automatic transmissions and foreign cars, transmissions had three speeds in order of use when starting from stopped: low, second and high. Can anyone verify that a Model T Ford had two speeds that were called low and high?

First is low and fifth is high. They originally called it that because (maybe) of low speed versus high speed. It’s only terminology and a way of describing things and isn’t really based on a technological theory. Reasoning out old lingo is difficult and sometimes people are resistant to just coming to agreement without trying to use logic to debunk the bunk that came before they were born. We all want a chance to talk a little sense into our forefathers. If we could go back in time; what name would we choose for the cellular phone? Thumbtack is already taken. Textifier?

Without confusing you with a lot of talk, 1st gear is the lowest and 2nd, 3rd, 4th, and 5th are progressively higher.

If you think in terms of feet of forward travel per engine revolution instead of engine revolutions per axle revolution, then fifth being the “highest” gear ratio makes perfect sense.

Now find something important to argue about! Like whether or not today’s popular music should still be called “rock and roll”.

Also, the best of luck to those who want to change the word “motorcycle” to “enginecycle”, “handgun” to “handrifle” which technically it is, and to those of you who cringe whenever the word “alibi” is used as a synomym for excuse.

You’ve learned a lot about the physics of gears in this post, but the concept of “higher” and “lower” gears can be thought of much more simply: when we talk of “down-shifting” we’re referring to going from a higher to a lower gear, and that means 5-4, 4-3, 3-2, 2-1. QED: 1 is the lowest gear.

I’ve always used the opposite terminolgy. I.E. 1st gear would be the shortest and 5th gear would be the highest. For example a Corvette has a 6th gear ratio of .57 which would be a very “tall” gear since even if the car was going 70 MPH the car would only be turning abour 1400 RPM. Same thing applies to rear end ratios. A car with a 4.56 rear end would have a “short” rear end.