Can someone explain gears to me?

bongofish

So as many of you know I'm a newbie to road biking but a fairly long time MTB rider.

Anyway with road bikes I'm a little confused as to which chain ring to be in at the front. They both have fairly easy gears and obviously the bigger one has harder gears for faster downhill pedalling or flat pedalling.

But I'm confused as to which one is people's most common to stay in. They both have sufficient enough rnage in them apart from the bigger one has them few harder gears for descents. But apart from them few gears I could do most my rides in either.

So when just pedalling at a reasonable cadence and doing maybe 14mph should I be in middle big chain ring or harder gear on small chain ring? Also when you then move to the large chain ring from the small chain ring if your riding a hard gear in small chain ring it instantly puts you into a really hard gear on the big chain ring ?

I hope this makes some kind of sense. Just don't know if I'm missing something?

imposter2.0

Seriously - and meaning no offence, but just try a few different gear combos and work it out - it really isn't difficult - and with your MTB experience, you should pick it up in no time at all...

bongofish

I feel like I have picked it up. But just feels a little cumbersome. Say I'm getting to a top of a hill and I'm in the small chain ring and then I start descending and think I need to move to the big chain ring . There's no gradually move up it's just bam your gears are now 3× harder or so it feels. Just didnt know if this was the norm or there was a work around.

imposter2.0

So shift up a couple on the rear to compensate - like I said, this is really basic stuff for someone who is not new to cycling...

webboo

At the same time as you use the left shifter to go in to the big ring, use the right shifter to go in to a bigger sprocket. It helps if you keep pedalling as you do this.

bongofish

That's what I have been doing. Just seems to slow the process down. Changing to the big ring and then moving gears back down . Just seems to stop the flow a bit. Trust me I k is its basic stuff but I'm used to 1x drivetrains. So having a double is new to me so just wanted to make sure I was doing it right and there wasn't something I was missing . When. I first picked up my road bike I didn't even know how to change gears until I asked someone where the levers were. Luckily they didn't start the answer by saying 'this is really basic stuff and you should knkw this'll like they are high and mighty....

N0bodyOfTheGoat

Generally, on the flat, I will use my 50T chainring with 18-20-22-25-28 sprockets on my 11-32 cassette. But not the 32 sprocket, due to cross-chaining not doing the chain many favours.

Uphill, I'll generally use my 34T chainring with 18 to 32 sprockets inclusive.

On easier cat4 hills that barely qualify to be categorised by Strava (that climb literally just over 262 feet and average 3% gradient or fractionally above) such as https://www.strava.com/segments/15752094 , if I'm feeling good and I fancy chasing my PB, I'll try and stay in my 50T chainring... But mentally keep note of what sprocket I'm in to try and avoid using 50/32.

imposter2.0

Bongofish wrote:

Luckily they didn't start the answer by saying 'this is really basic stuff and you should knkw this'll like they are high and mighty....

The only reason I put it that way is because you have frequently made the point that you are not new to cycling. Someone who is a 'long time MTB rider', I would have thought, would already familiar with riding derailleur-equipped bikes. What MTB have you been riding?

lettingthedaysgoby

There’s a couple of GCN videos that might be of use:

https://youtu.be/j4McWdrImRY

https://youtu.be/_-vguUGj8pg

bongofish

Imposter wrote:

Bongofish wrote:

Luckily they didn't start the answer by saying 'this is really basic stuff and you should knkw this'll like they are high and mighty....

The only reason I put it that way is because you have frequently made the point that you are not new to cycling. Someone who is a 'long time MTB rider', I would have thought, would already familiar with riding derailleur-equipped bikes. What MTB have you been riding?

I ride a Vitus Sommet
And a calibre triple b

Prior to that I had the board an FS Pro

Zendog1

Into a strong headwind small ring, tail wind big ring.

I imagine it's the same with hills but coming from Norfolk they are not an issue.

stueys

Rough rule of thumb is that shifting small front chainring to big one will require you dropping down 2 gears at the back to keep the gearing consistent. That's pretty much what my DI2 does when I run it in semi-syncro mode (which isn't often).

When to shift is entirely personal preference. There is a lot of overlap on a double, so it really depends how the gearing feels to you, there isn't a right or wrong. I like to spin at a high cadence so tend to hang onto the smalll chainring longer than lots of people I ride with, it just feels more natural to my riding style. But that's personal preference.

The only time you might want to plan ahead is when approaching a climb, it normally makes sense to drop the rear cassette down and run in the small chain ring. That way you aren't trying to do a front chain ring shift under load when the chance of dropping the chain is higher.

keef66

As you've discovered there is a big difference between the big 50t chainring and the small 36 or 34t one, and you'll usually have to shift a couple of gears at the back to maintain a comfortable cadence.

That's one of the reasons I like my triple chainset so much: big 50t ring for downhill / tailwind, modest drop down to the 39t middle ring for 95% of my riding, then another manageable drop to the little 30t ring for steep hills / vicious headwinds / winching myself home when I've not eaten enough.

You should also bear in mind that in the big ring you should avoid using the 2 largest sprockets at the back and in the small ring avoid the smallest 2. Google cross-chaining.

svetty

You will find it easier to adapt to multiple fron rings if you have a relatively small difference between them. If you are a strong rider and live somewhere relatively flat I'd suggest a 53/39, if you are not as strong with steeper hills a 50/36. With only a 14 tooth difference the jump between rings is much less annoying.

pamplemoose

Back in my day MTBs had triple chain sets! Seriously though, just get used to using both shifters at once. I imagine it'll take some adjustment after using 1x

CiB

There are no rules. Gears exist to allow you to maintain a cadence within a suitable and comfortable range for different road speeds, terrain and conditions. Given that the normal cadence is supposedly somewhere around 85-100 you just need a way to identify your own cadence (Garmin etc) and then pick whatever combination of gears allows you to hit it. You could also calculate all of your available ratios by dividing each rear cog into each front (53/12, 53/14 etc), and then from that list see for yourself how much overlap there is and where it occurs, particulalry wrt to cross-chaining (already mentioned above).

Fwiw I'll happily swap from big front medium rear to small front smaller rear (and vice versa) to achieve an almost identical ratio, either because it's just a bit nicer or because there's a hill looming and I might want to be ready for it.

Moonbiker

small front smaller rear

Cross chaining = noob

CiB

Moonbiker wrote:

small front smaller rear

Cross chaining = noob

...where smaller is a relative term, i.e smaller than the current selection. 19 to 17 is a drop to a smaller cog; it’s not cross-chaining.