Numpty Gearing Question (esp for climbing)

[Sunny Portrush]

No matter how many tutorials I watch, I still dont fully understand gearing lol.

Basically, I`ve just got back from a cycling holiday in the Alps and i bike I hired came with ultegra compact 11 speed groupsets with 11-32 cassettes on the back giving 34-32 as the easiest gear. I found it relatively easy to spin up the climbs but it made me wonder about my own bike.

It has Shimano 105 11s 50-34 with 26-12 on the rear cassette (I just counted the teeth to make sure!) giving my easiest gear as 34-26.

How much harder am I making things for myself by using the gearing on my bike as opposed to the hire bike gearing or are they not comparable?

I know some people will be slapping their foreheads in disgust lol

 

[si_c]

Depends on the hills near you. If you live on the flat then probably no harder.

 

[Cycleops]

Nobody's going to be slapping their foreheads in disgust.
If you find your current set up manageable stick with it but it wouldn't take too money or effort to change to the lower gearing of your hire bike if you feel you could make use of it.

 

[raleighnut]

You'll probably need to change to a GS version of the rear mech to run an 11-32 though.

 

[Sunny Portrush]

Cheers all - I live beside Edinburgh which likens itself to Rome in both supposedly being built on seven hills so it can be hillyish around here (not Alps style tho!)

I would just like to go uphill something quicker than snails pace lol

 

[sleuthey]

How much harder am I making things for myself by using the gearing on my bike as opposed to the hire bike gearing

23.1%

 

[Sunny Portrush]

23.1%

Seriously?

I`m slow going up-hill, I`m slow going downhill and I`m slow on the flat. I love cycling!

 

[ozboz]

I swapt from an 11-25 to an 11-36 cassete, the 25 was to hard for me on hills , to do it I had to get a longer cage d rail’r and bought a Wolfs Tooth extender for the d rail’r and a longer chain , sweet as a nut now !

 

[simon.r]

23.1%

He’s right:

Gear chart using Gear Inches
For 700 X 25 / 25-622 tire
With custom sprocket(s)
34 32 - 28.0
23.1 %
34 26 - 34.5

https://www.sheldonbrown.com/gear-calc.html

 

[Sunny Portrush]

So, it`s not me, it`s the bike - phew!!!

 

[sleuthey]

He’s right:

Gear chart using Gear Inches
For 700 X 25 / 25-622 tire
With custom sprocket(s)
34 32 - 28.0
23.1 %
34 26 - 34.5

https://www.sheldonbrown.com/gear-calc.html

Thanks. But I never used any charts. Just did it manually using basic maths. In other words I ought to get out more!

 

[Specialeyes]

FWIW I get out lots and also did 6/26 (difference between largest sprockets/largest current sprocket) = 23.1%, so don't feel too nerdy

 

[CXRAndy]

I use bikecalc for calculating my cadance and or speed with different ratios of gearing. The results have been spot on compared to real world riding. I use a triple crank 48/36/26 and various cassettes depending what Im doing. I have 11-40, 11-32 and 11-25

 

[graham bowers]

Cassette
Cassettes with 32 or even 34 teeth are available so you could replicate the ratios of the hire bike or even an easier 34:34.
For example https://www.sjscycles.co.uk/cassettes-11-speed/?ratio=11-34&ratio=11-32&brand=shimano&groupset=105

Chain
You will need a longer chain. https://www.parktool.com/blog/repair-help/chain-length-sizing

Rear derailleur (RD)
It's most unlikely your RD will have the capacity. Conventional wisdom is to change it for a longer cage version. Shimano publish compatibility info
https://productinfo.shimano.com/download/pdf/com/2.3/en

Many seem to have had success by just lowering the RD with a Wolf Tooth extender that was mentioned above. I put a 34 max tooth cassette on my 10 speed ultegra bike and the standard short cage RD would shift to the 30t sprocket, so now it's 9 speed! However yesterday I ordered one of these that does the same job as the Wolf Tooth offering and am hoping it'll enable shifting to the 34 sprocket.
https://www.sjscycles.co.uk/gear-spares/aluminum-rear-derailleur-hanger-extender/

I can't decide if this has a longer drop:
https://www.sjscycles.co.uk/gear-spares/sunrace-rear-mech-extended-link-for-wide-ratio-cassettes/

Maybe you will need a new RD to get it to work, however it is do-able to modify your bike for easier gear ratios.

 

[Dogtrousers]

How much harder am I making things for myself by using the gearing on my bike as opposed to the hire bike gearing

Some very good answers above. My answer to this question is quite a lot. The very idea of a 34/26 bottom gear has just given my legs a nervous breakdown.