Yes that's good, I have used that exact item with great results, just be sure to get the right size.

The other question is what load is the OP carrying.

I've done a little loaded touring in mountainous terrain and find that low gears make life a heck of a lot more enjoyable.

BTW- a 22 tooth chainring with a 34 tooth rear cog will get 4.6 mph at 90 rpm with 700 c wheels.

I am glad you brought up cadence. That can be an issue. Try revving at 90rpm just to stay upright when your normal cadence might be 80 or even 85rpm. If your cardio fitness isn't up to scratch, a rider will have issues trying to sustain 90rpm or more up a long climb.

Personally, I would prefer the higher tooth count on the small ring and stand to pedal. Then again, much depends on the load and the ability of the frame to handle that without flexing.

I will make the point again that as the tour progresses, the rider's fitness and strength will increase.

I find this completely insulting.

Read the OP's comments about being lost amongst all the discussion about the "science" of it all.

And unfortunately, your high-school maths doesn't take into account a number of other factors, including the rider's weight, load, the inclines expected, tyre width and inflation, headwinds, and fitness and strength of the person in question.

The OP really needs to experiment. For the cost of a 22T and 24T granny, he can take a trip out to the Kimberleys with his car, and do some riding there and find out what really does suit him.

is "OP" is meaning me im 70kg, bike 15kg, gear worst case 30kg, that's if I end up having to carry my friends stuff if they struggle

??

It doesn't matter what you think, Rowan. The OP got a precise help that completely took care of his concerns.

Yes, "OP" means original poster

30 kg is a lot of weight to get up hills. I weigh the same as you, and with a 16kg load, I often use my lowest gear on steep or long sustained grades. Some of our mountain passes here require climbing for 65 km; nothing really steep, mostly average <6%, but with steeper pitches.

Rowen,
90 rpm is my normal cadence. I just shift down to lower the cadence if needed. I can easily handle my loaded bike at 3.5 mph with very little wobble, but the hill has to be steep enough to give me substantial pedal resistance. It still beats pushing a bike up a hill.

Barrettscv thanks for all your help I know what I'm ordering now, just have to wait for it to arrive now. Thanks again

Have a great tour and post pictures!

I too have used that exact chain catcher thingee with great results.
Really good advice here, especially the example of barret and what he climbed in Italy (?) how much he weighs and about how much weight he had.
Can't recall if I or others have written, but with lots and lots of climbing, you will feel every 5kg more of stuff a lot, so we can give gearing recommendations, but what you can do is to start to put your stuff together and actually see how much it weighs, and perhaps over time try to figure out stuff you dont need.
Again, cant recall if this was mentioned, but the rough estimate of trying to keep your bike weight + load to half your body weight is a good one. I'm about 140lbs , so a 70lb bike+gear total is about what I have toured a lot with (and sometimes less, never bad to be less...)

My goal is to have my gear 20kg or less, but odds are I will end up carry some of my friends gear up big climbs if they struggle. I am going to swap out to a 22t chain ring and and 11-34 cassette so I'm hoping I will be able to climb anything, with it.