1×11 conversion to 2×11…?

I’m about to fit a 1×11 (34T by 11-46 SLX) to my 2014 Giant Anthem. I was just wondering – If I find this set up undergeared (I’m coming from a 3×9 set up) could I easily add a new front chain ring and go something like 30/42 by 11-46 SLX ? Can you convert a 1×11 to a 2×11 fairly easily ?

Possibly – Shimano give two capacities for their rear mechs, one for 1x and one for 2x. Basically you need to account for the difference in teeth at the chainrings as well as the spread of the cassette. Your proposed 2x setup needs a capacity of 43T.

There’s a chart on this page: https://guides.wiggle.co.uk/rear-derailleurs-buying-guide that shows that for that capacity you’ll need a long cage rear mech. That chart also reckons that the largest cog on the cassette would be 42T but I know my wife has a 46T on her bike with a Shimano rear mech so it’s possible.

Edit: I went from 3×9 on a 26″ wheeled bike to 1×10 (30T front, 11-40T rear) on a 29er and my total range dropped by 3 ratios. I chose to lose one at the bottom end and two at the top. After a month or two I didn’t really notice the lack of range, I’d rarely use the top end anyway.

This is what you need to have a play with. It will show the spread of all the gears, 1x or 2x based on what you have or want to do. It will also allow you to visually compare 2 different setups side by side.

http://ritzelrechner.de

I would indeed work it out on the above app. And avoid fitting a front mech if at all possible, even if that means a 32t ring.

Unless you regularly ride your mtb for long periods on the road, you’re not going to want a 2×11; there’s easily a low enough gear with a 46t cassette for anything that’s worth riding. Besides, front mechs are horrible.

JP

Avoid 1x if at all possible, function > fashion

Easy.

First – check your frame will take a front mech and, preferably, the side-swing type.

Shimano cranks are all 2x, even if fitted with a single ring. If your single is a Narrow/Wide then you’ll need to change it to a ramped ring.

You should only need a long cage mech if you are trying to go 3x.

Ignore the folk who either lack the mechanical nous to set up a front mech and/or can’t coordinate their hands to operate a front shifter.

Every time I ride a bike with a front mech down anything meaningfully rocky I lose the chain these days. Never lost the chain on a 1x setup so for me I won’t go back on my mountain bike.

As above, the obvious question is whether your frame can take a front derailler. The other practical question is fitting a remote for a dropper post. I tried 1×11 but switched to 2×11 for the range, but ended up having to put the dropper remote on the RH side above the bars. Perfectly functional, but doesn’t look elegant and vulnerable in a crash.

Avoid 1x if at all possible, function > fashion

This ‘function’ thing, it’s the bit where you don’t lose the chain over bumpy ground, right?
Understand that people have different needs. Sounds like you don’t need it. Lots of other people benefit hugely from 1x. Myself included.

Avoid 1x if at all possible, function > fashion

Nonsense. I started on x1 purely for functional reasons in 2009 when it was very unfashionable. It virtually didn’t exist then. The rest is history but fashion just followed function. It’s so obvious for mtbing. I guess you don’t have much experience of it.

Some of my bikes are 1x, some are 2x, one is 1×1.

all have thier place.

Ignore the folk who either lack the mechanical nous to set up a front mech and/or can’t coordinate their hands to operate a front shifter.

I assume you have a manual choke on your car.

Setting up and using a front mech is very easy but it doesn’t mean I want one. So there may be a third possibility

Uh, oh!

Could you children wait a while, I need to nip down the shops to get some biscuits.