Hi,
which of the combinations below is easier in climbs?
1. front and back 34 teeth wheels
2. front and back 36 teeth wheels
Thanks

All other things being equal, should be roughly identical as the ratio of 1:1 is the same. I suppose there could be some minor friction differences due to the number of teeth, but that's definitely rounding error stuff. You'd never notice it in real life.

They would feel identical.

Bike gear ratios are mostly over drive ratios, like 52/13 = 4/1. Really low gears go below 1/1, like my 30/36 = 0.83/1. The smaller the first number, the lower the gear ratio and the easier bit is to pedal up a hill, but slower. I ride grades up to 13% and the 30/36 works for 4-6 mph.

Thanks for your answer.
you say that "The smaller the first number, the lower the gear ratio and the easier bit is to pedal up a hill", but as I know, the bigger the back wheel the easier bit is to pedal up a hill. you have 30 back wheel and 36 front wheel and you can climb a 13% grade but (for example) you can't climb 16% grade.
if you would have 34 back wheel and 36 front wheel, then you could have climb a 16% grade. and this ratio is bigger than 0.83, not smaller.

Yes.

OK, assuming you are serious, the bigger the rear the easier, the smaller the front the easier.

Your original question was about when both front and rear are the same number of teeth.

Are you now moving the cheese?

Oh, by the way... Welcome to BF!

Just for your reference, it is normal to call the front the chain ring and the rear are called cogs. Some call the rear gears, but that gets confusing as we talk about what gear we are in meaning the combination of chain ring, cog, and wheel size. Some people call the front a chain wheel, but that is somewhat anachronistic. Wheels are what the bike rolls on, with tires mounted on them.

shroni2807 ,
This page seems to provide a good introduction to bicycle gearing, terms & how the ratios work. Click the>>>>> LINK

Welcome to BF

Barry

It's just the overall ratio of front/rear teeth that matters. The smaller this ratio, the easier it is to climb with.

So in your examples above. 36F/30R = 1.2 (not 0.83, which is actually the inverse). 36F/34R = 1.06 (which is less than 1.2 and therefore easier to climb)

Yes, the front gear is a "chainring" and the rear one is usually referred to as a "cog", although "rear gear" is sometimes used, too. Given a specific wheel size, gear ratio is what's important, and as "ratio" implies, it's a direct result of the chainring teeth divided by the cog teeth. You'll see 'gear inches' used, and this is the gear ratio times the wheel diameter, in inches. Thus an 34/34 gear combination on a 26" wheel is 1 / 1 * 26 = 26 inches.

Good to know.

Sorry, but I was comparing 4/1 to 0.83/1. I have no clue what you're talking about. Use proper terminology. The front is a chain ring, the rear is a sprocket. Drive ratios are chain ring/ sprocket.
​​​A 36/34 is 1.06/1. It's more difficult to ride up a steep grade with that ratio, compared to my 30/36 = 0.83/1.

DaveSS said 30/36, which is indeed 0.833.
34/30 is indeed >0.83