Hi

I currently have a hybrid and would like to get some thinner wheels as I pretty much only road bike now.

My current tyres state 54-559 26x2.1

The move I look at sizing the more confused I get. Would someone please be able to tell me what size thinner tyres would be suitable?

Cheers in advance

Welcome!

There are two basic tire size nomenclatures. You can read more about it here: https://www.sheldonbrown.com/tire-sizing.html

To cut to the chase, your wheels have a 559mm diameter (at the bead seat), and your tires have to match that. These are commonly known as 26" tires, even though the wheel is not 26" in diameter. The way it started, the tire's diameter was 26", but with the advent of all sorts of different widths, it just doesn't work out that way anymore. The least confusing way to refer to a tire's size is by its ISO size, which in your case is 54-559. That is, the tire is about 54mm wide and it fits a 559mm wheel. Problem is, in many parts of the world, folks really only know the "other" sizing method, calling them 26x2.1, or 26" tires that are 2.1" wide.

You're probably looking for something like a 38-559, which would be a 26x1.5 tire. Or maybe even a 35-559, which might be labeled a 26x1.4. Lots of tires exist in these sizes, you may just have to play with the size nomenclature on websites to find what you want because sizing is, unfortunately, not quite standardized.

Something like 26 x 1.5" to 26 x 1.75" should be a nice all rounder.

What kind and model tires do you already have on there - that would help us with recommendations, and how much money are you looking to spend?

Additionally if you want to reduce pedalling effort look for a tire with smoother or no tread. Most hybrid tires have a fair amount of tread that is not needed for road and light trail riding.