Changing from 1st to 12th

[ndwgolf]

Something got me thinking today so I will ask the crowd. When going up hill while changing gears from say 8 to 1 but once you get to 1 you now need to drop the front ring to the smaller ring........ how do you go about that because you will then be going to the very easiest gear instead of the next gear if you know what I mean??

Neil


I'm a trendy consumer. Just look at my wobbly bog brush using hovercraft full of eels

[Marcus Aurelius]

Something got me thinking today so I will ask the crowd. When going up hill while changing gears from say 8 to 1 but once you get to 1 you now need to drop the front ring to the smaller ring........ how do you go about that because you will then be going to the very easiest gear instead of the next gear if you know what I mean??

Neil


I'm a trendy consumer. Just look at my stupid phone.

You’re talking about ‘block shifts’. The way to stop the great big jump in cadence you inevitably get with this kind of shift / the best thing to do, is practice with up and down hilly riding. Then work out a ‘gear shift plan’ so if you know that the hill is about to get big on you, prepare for the shift in chain rings by getting a more synced gear ready on the cassette, before dropping the chain ring. You could also help by choosing a more suitable chainset, with less difference in teeth between big and small.

[simonhill]

I would say, don't go all the way down in that (middle) ring, change to smaller ring earlier. I do this for a number of reasons, not least chain line.

If I see the hill is big or long, I don't go below 3rd in middle (which I rarely do anyway). Then when I need to change down it is to 3rd on small ring. This gives me 3 gears to use.

But isn't this obvious, have I missed something?

[mjr]

To change first to twelfth on my bike with that many gears, I'd have to shift front one ring and back something like five. Remember, they're not usually sequential 1-11, 12-22 and so on. It's something like 1,2,4,6,9... on big ring, 3,5,7... on middle or whatever. www.gear-calculator.com will work this out better than me!

[ndwgolf]

But isn't this obvious, have I missed something?

maybe obvious to you but not to me hence the initial question. I’m just trying to learn the best way to operate the bike without screwing up.
I’ve got it now....... thanks

Neil

[simonhill]

Sorry, wasn't trying to be rude, glad to be of help.

[PDQ Mobile]

Double shift.
When you need to go to the front "granny" ring at the same moment shift the cassette back a couple of cogs .
That helps preserve cadence and the momentary chain slack can help a reluctant (under tension) front change too.
And you still got a couple of gears then left in your "wallet".

[ndwgolf]

Sorry, wasn't trying to be rude, glad to be of help.

No worries
Thanks

[Airsporter1st]

Presumably, the electronic shifters are/could be programmed to take care of this, shifting both front and rears practically simultaneously. If not, why not?

[ndwgolf]

Presumably, the electronic shifters are/could be programmed to take care of this, shifting both front and rears practically simultaneously. If not, why not?

I would be interested to find out some more about that?
Neil

[Jamesh]

I do find with the newer compact chainset the drop from 50 - 36 or 34 is quite a large one. Much more than the traditional 52 - 42/39.
Tend to have to drop a couple of cogs at the back to keep up cadence.
Also tend to be on the bottom of block on inner chain ring or top of block on outer which isn't ideal!
A triple is probably a better option in that regard?

Cheers James

[AndyK]

Presumably, the electronic shifters are/could be programmed to take care of this, shifting both front and rears practically simultaneously. If not, why not?

I would be interested to find out some more about that?
Neil

Shimano's Di2 offers this ("Synchronized Shift" mode). You can even customise its shifting choices if you want. I can't say I've tried it.

[ndwgolf]

I have Di2. I guess it’s tine to read the manual
Neil

[drossall]

I think about it as the front gear giving ranges. They necessarily overlap. If I know I'm hitting a hard hill and I'm going to want the low range, I may as well get there as soon as possible. In general, the thing to avoid is difficult changes when you're already struggling - partly because it's just harder, and partly because you'll have the gears under load in your effort to get up the hill, and gears change better if you can slacken off the pressure just slightly as they change.

[andrew_s]

Quite a number of people do grumble about the size of the gap between chainrings on a compact double chainset, with them having to change up 3 cogs at the back when they drop the chainring down to the small chainring.

The ratio between sprockets in the middle of the cassette is similar to that between sprockets at the low gear end, so it doesn't normally make much difference when you change chainring.
(11-28 11sp, 50/34=1.47, 28/19=1.47, 21/14=1.5; quoted sprockets are 4 shifts apart, so you actually shift 3 so you don't get the same gear you were in before the front shift)

Your only option is to be as quick with your change as possible. That means simultaneous front/rear shifting (which is possible with down tube levers, so Di2 isn't necessary, though it is easier), easing off on the power during the change, and changing whilst your cadence is still reasonably high.

Of course, the real cure is to use a triple, with the chainrings closer in size .