I've read this and this and I understand the good ways and the bad on how to ride up hills. In fact I consider myself a good hill climber (roadie), but some of the guys I ride with are beating my KOMs because of their gearing. Two of them are now on 32s whilst I only upgraded from 25 to 28. Yeah I know, I should have gone up to 32 as well to match. BUT, I reckon my 28 with the right gearing on the front will make all the difference. So what are good gearing ratios to determine the right gears for both front and back, so that I can keep my cadence around 70-80 or 90 and still have decent speeds (more then 15km/h)? Do I have to provide personal specs, weight, etc? Thanks
@hillsons has already pointed out that one key is to find your ideal cadence. Totally agree, but lets unpack that a bit more ...
You don't mention how steep these hills are, how long they are, or how your weight and size compares to these riding buddies.
Assuming the hills are longer than can be overcome by a good run up, what gear you need depends on many factors
how steep is the hill,
how strong you are, compared to the total weight of you and your bike,
how mentally tough you are - what level of pain you are willing to endure,
how warmed up you are (minimum 30 minutes, maybe 60 minutes).
All these factors are inter-related, but it all boils down to the fact that you are using a lever (via your pedals, gears, and wheels) to lift your weight X meters up the hill in less time than your competitors. Lower gears give you a longer lever. Lower weight means you don't have to push as hard. Your strength and aerobic capacity determine how fast you go and how long you can keep it up. Plus the X factor: in competition it's not the fittest, or strongest who win, because at a given level everyone has often pretty much the same physical capabilities. In this situation it's the most determined, the one who can stand the pain the longest, who wins. One family member became a national champion saying just one more tree, or just until that post, and the next. And the next. And smiling to psych the others out.
So, to be competing, either with friends or in open competition, if it's comfortable, you are doing it wrong!
If you think lower gears will help, then you are right. They will help; it will be a self-fulfilling prophesy. For a while. But in the end, you will need to address the central issues. Your strength. Your endurance. Your pain threshold.
It can be a great journey. Enjoy.
It's not about numbers, it's not about this many teeth should be in the front and this many teeth in the back. There's no right answer here, and no one on this forum can say what your best fit is. It's 100% your responsibility to find out what works the best for you and what lets you achieve your ideal cadence and beat your mates up the mountain.
The answer to how to make the 28 like a 32 by adjusting in the front
That is 14%
Let assume you had a 36 up front now
32 / 36 = 28 / x
x = (28 / 32) * 36
x = (7 / 8) * 36
x = 31.5
31 - 32 is kind of small for a road bike and the front derailleur might not handle it.
If you want a lower gear you are going to need to add teeth in the rear or take them away in the front.
It is not about a calculator to tell you what gear you need. If you cannot hold your target cadence on a climb then you need a lower gear. If 32 is working for your buddies and you hold with them on the flats then why not try a 32.
On a 32 / 28 a cadence of 90 is only 13 km/h
On a 36 / 28 a cadence of 90 is 14.6 km/h
If you cannot hold a cadence of 90 on a 36 / 28 then you are not going to get the speed you want