Gearing Explained – How to choose what you need

Picking the right gears has a dramatic effect on how your bike rides and how much (or little) you wish to suffer when the road heads upwards. Our gearing explained guide will hopefully make you a little more gear savvy when it comes to your bikes spinny bits.

GEARING EXPLAINED

We can well understand the confusion when it comes to deciding what gear ratios your new bike should have. It’s easy enough for experienced cyclists to become bamboozled by gearing options let alone anyone looking to take up cycling for the first time. Especially when faced with options such as 10, 11, or 12 speed and cassette ratios of anything between 11-28 and 11-50.

So we’ve put together this gearing explained beginner’s guide to hopefully help you decide which is the right fit for you.

So, when we refer to gearing, what specifically are we talking about?

Simply put, it’s the chainset at the front and the cassette (also referred to by some as sprockets or cogs) at the rear. More specifically the number of teeth each component has. The general rule of thumb is that the more teeth a chainring has, the harder it is to pedal. However, the opposite is true for the rear cassette, the more teeth there are, the easier it is to pedal.

Therefore, if you wanted to make ascents easier you would want smaller chainrings at the front and larger sprockets at the rear. With us so far?

Now for the nitty-gritty. Just how does one go about selecting one option over another. And how does your selection affect how the bike performs?

Chainrings

A chainset will typically consist of 1, 2, or rarely 3 chainrings. Otherwise referred to as One by, Double and Triple respectively.

To put it as simply as possible, the smaller these are then the easier it will be to spin the pedals.

Most bikes will come fitted as standard with chainsets that have 1 or 2 chainrings. If it is a double chainset there will be 2 chainrings, an inner and outer. The inner is always by virtue of its small number of teeth the climbing ring. The larger diameter outer chainring is better suited to flatter terrain and descending.

Ribble is renowned for its bike customisation options, which means that virtually every bike in the range is fully customisable. You can select chainring sizes and cassette ratios to suit your riding needs.

34/50

You may see or hear this referred to as ‘compact’. Both the inner and outer chainrings are quite small, which makes pedalling easier. This is especially handy on climbs and the 34-50 ratio chainset has found great popularity among novice cyclists or seasoned roadies looking for more assistance on the climbs.

There is, however, a trade-off. The relatively small diameter outer ring will cause you to ‘spin out’ more quickly on descents or on the flat (if you’re fast and fit enough). Spinning out is when you run out of gears and your legs spin like the clappers but to little effect.

36/52 – 34/53

Shimano 12-speed groupsets now include a semi-compact 34/53 ratio.

Known as ‘semi-compact’ this is an intermediate option for riders who still want help on the hills but desire more speed on the flats and descents. Rather than the 34/50 of compact, you now get 36/52 or 34/53 chainrings.

39/53

Ok, so it’s not strictly 39/53, but it is so very pretty!

Back in the latter part of the 20th century, almost every new bike would arrive with a ratio identical or similar to this. It was for a time the standard ‘race’ setup and dates back to a time when you bought a bike that simply came with double or triple gearing. Today’s racers will still use something very similar, albeit with a slightly larger outer ring. This ratio is fast on the flat but offers little assistance on the climbs. It is, therefore, only the supremely fit or dedicated racers who use this.

1x Single Chainring 

The lack of a front derailleur adds simplicity and greater chain security over rough terrain.

The relatively new kid on the block is the single ring chainset. Or 1x as it is referred to in the cycle industry. 1x isn’t actually a new concept. In fact, it’s been used in the MTB sector for a number of years. Its transition to the drop-bar bike sector, however, has been surprisingly slow considering the advantages it offers in certain scenarios.

Let’s take the Gravel Bike boom, for instance. The more difficult terrain encountered when riding off-road demands a lower gear range than you would typically use on the road. Enter the 1x system. Its popularity now means that nearly all gravel and all-road bikes come with it as standard.

With only a single chainring to worry about, you don’t need a front derailleur. By removing this you instantly eliminate any possibility of a front end chain jam. When riding off-road mud and debris had a tendency to clog up the derailleur which could force the chain to unship when shifting.

With the 1x system you can expect to see chainrings as small as 30t or as large as 44t specced. This will depend entirely upon the model of the groupset.

Cassettes

A wide range cassette, note the increase in cog size. The closer to the top, the easier it is to pedal.

A cassette is a collection of cogs that sits on the rear hub and provides a select gear range for every riding discipline. In direct contrast to the chainrings, the larger the sprocket is, the easier it is to pedal. Large sprockets are more advantageous when climbing.

The groupset that a bike is supplied with will determine whether the cassette will have anything between 8 and 13 sprockets. Entry-level groupsets will typically have between 8-10 sprockets, whereas mid to top-tier will have between 11 and 13.

You, therefore, need to select an appropriate cassette ratio for the terrain you expect to ride most often. For most assistance on the ascents when riding on the road an 11-32 to 11-36 may prove most beneficial.

Closer ratio cassettes such as 11/25, 11/28 or 11/30 are better for riders with a high level of fitness or who prefer flatter terrain.

1x systems are equipped with cassettes that have a much wider spread – anything between 11-42 and 10-50 at the norm.

Gear Ratios

Climbers gearing – 34/50 with 11/32 or 11/34 Cassette

What we here at Ribble refer to as a ‘climbers’ ratio. It’s what we recommend for beginners or existing road riders who want plenty of assistance on the climbs. With both a small and large chainring at the front, there’s no need for a massive cassette at the rear.

The advantage of this is that when you change gear the jumps between each individual gear are smaller. The smaller the steps between gears are, the smoother the action is when shifting from one sprocket to the next. A smoother shift results in less interruption of your pedalling rhythm (cadence). This is more pronounced with 1x systems due to their much bigger sprockets.

Semi-Compact 36/52 with 11/25 to 11/34

Amateur racers and riders with a decent level of fitness may benefit from this setup. It still offers some assistance on the climbs thanks to its 36t inner ring. However, it’s the 52 teeth outer chainring that anyone opting for this setup really desires. This setup offers the following benefits;

  • The gap between gears is relatively small. Ideally, you want to keep this number as small as possible. The reason for this is to avoid loss of pedalling rhythm when changing gear. A loss of rhythm will also affect power output making it less efficient. Therefore, opting for a smaller spaced cassette like an 11/25 or 11/28 avoids this jump when changing gear.
  • The gears do not ‘spin out’ as fast when descending. Spinning out is when you descend at such a velocity that you can no longer pedal. Sure you can spin the pedals but there is no traction on the chain. A large chainring at the front means that you can pedal for longer before losing chain traction.
  • Specifying larger chainrings and/or closer cassette ratios also makes the bike faster on the flat.

Single Chainrings

The gearing loadout of a bike will depend entirely upon what type of bike you go for and what groupset it comes fitted with. A hybrid style of bike will often have a chainring as small as a 32t at the front and a road ratio cassette of 11-32 to 11-36 at the rear.

Allroad or gravel bikes tend to have a larger chainring of approximately 40 to 44t. This is then combined with an MTB ratio cassette of anything between 11-42 and 10-50t. In reality, the gear range will be markedly similar and you are less likely to be offered a choice of gearing.

We hope this guide helps you gain an understanding of what to choose when buying a new bike. If, however you still need assistance then please do not hesitate to get in touch.


If you are in the market for a drop-bar bike, which should you choose? In our guide, we compare all-road bikes to gravel bikes and endurance bikes to help you decide.


Looking to take up cycling? Check out our guide for the answers to most of the usual rookie questions.


Looking to get fit or save some money. Find out why an e-bike could just be the solution that you are looking for. Click here to find out more.

15 Comments
  1. Interesting post. Glad to see cross chaining wasn’t mentioned 😉

    When I ordered my CGR AL at the end of 2019 it came equipped with 34-50/11-25. I never questioned that at the time and I still run that configuration but it’s not mentioned here.
    Is that because that setup is more specific to gravel/road crossover riding?

    My rides typically are a mix of forest trail and (badly) paved roads and it’s been working quite well for me, even after putting 16000.

  2. Hi Ragnar,
    Thanks for getting in touch. The blog was never meant to be an exhaustive list of all of the different gear ratios but was only ever intended to give examples of the most commonplace ratios. I have to say that a 50-34 chainset with an 11-25 cassette is a more unusual combination as it mixes a compact chainset with a race ratio cassette. It would be unusual to find this specced on any of our bikes so it would be interesting to see your original order information. It is also worth noting that every bike’s gear ratio is fully customisable before completing the order. We give customers full control over what cassette and chainring ratios they would prefer on their new bike. By all means, feel free to get in touch and we will review the original order details.
    Best Regards
    Team Ribble

  3. I did away with my three-ring chainwheel last year because I live in the city of Valencia in Spain and the surrounding terrain is flat. My days of climbing mountains are over so I didn’t need the front chainrings. I settled for a 50t single ring. I have a 7-speed freewheel set at the rear with a very wide range, so I can still climb the occasional hill. The three big advantages of doing away with the front chainwheels are the reduction in weight, the reduction in wear on the chain and the simplification of the cables. I wonder about the use of cassettes. Yes, you can customise them to your needs but the other supposed advantage in that you can replace just one that is worn seems a bit weak. I’d be interested in your views on freewheel sets versus cassettes..

  4. Hi John,
    Thanks for getting in touch, from your description of a triple chainset and a 7-speed screw-on freewheel you must own a retro classic of a bike. Triple chainsets experienced a decline approximately 5-10 years or so ago when component manufacturers launched compact double chainsets that offered much the same gear ratio as a triple but without the additional. SRAM, Shimano, and Campagnolo have largely phased out triple and it is a similar story with screw-on blocks. When I first started out in the industry some 25 years or so ago, the screw-on freewheel was already in decline. Cassettes have gradually gained the ascendency until today there is hardly any call for screw-on blocks and very few of the type are still manufactured. Yes, you can, in theory, buy separate sprockets for a cassette.
    However, in reality, most people tend to change out the entire cassette rather than replace worn sprockets. If one sprocket is worn out it is highly liable that the others won’t last too much longer. Plus, having one new sprocket working alongside partially worn sprockets is liable to cause shifting issues. A cassette is certainly easier to clean than a screw-on block, however, as you can separate the sprockets to treat them to a thorough degreasing.
    Best Regards
    [email protected]

  5. Interesting article. I’ve recently bought the Level 1 wheel set to extend the riding season for my Endurance SL disc (currently running on carbon deep section wheels) and have opted for 11/34 cassette. The carbon wheels have 11/32 cassette. I’m wondering if I can run the new wheels with the existing chain (it’s not worn , I’ve checked, or will I have to put on a longer chain? I’ve got Ultegra Di 2 and the longer derailleur cage.

  6. I have a 1970’s Mercian and a modern Cannondale. On the Mercian, I use a 28-14 six speed screw on freewheel, (The rear drop outs aren’t wide enough to take either a cassette or a screw on with more cogs), wiith a 28, 38, 50 triple chainring. The Cannondale came with a 34-11 ten speed cassette and a compact 34-50 chain ring set. As you will note the lowest ratio on both bikes is 1:1, which is much lower than I had on the Mercian when it was new, 42 to 28, but my legs were 40+ years younger then! Today the ratios on both bikes are similar, I never use the two smallest sprockets on the Cannondale with the big ring anyway. Both bikes climb hills pretty much as comfortably for me at the pace I can climb today. Albeit either 34×34 or 28×28 means I climb at not very much more than walking pace.,
    The one issue I recall with screw on freewheels, comes when you need to remove them. The torque produced by the rider, especially a strong rider using low gears, on a fully laden touring bike causes the freewheel to become screwed on very tightly. There is no such problem with a cassette as all the sprockets are splined and held on by a lock ring that doesn’t transmit torque.

  7. None of the gear options available are suitable for guys in their late 70’s riding in the Alps or Pyrenees especially if you want Di2. Previously with mechanical SIS I managed to use a 24 inside ring on an Ultega triple with a 28 sprocket on a 10speed cassette. Now the best I can do with Di2 on a road bike is a 31 inner using an Ulega GRX chainring which works OK with a SRAM 36 tooth on a 11 speed cassette but because I need to ‘Spin’ its still not low enough. If there is a Di2 solution for lower gears can someone tell me please?

  8. Hi Stephen,
    Thanks for getting in touch,
    If you are running a 32t cassette currently with a medium cage rear derailleur, then you should be able to use the existing chain.
    Best Regards
    [email protected]

  9. Hi Chris,
    You’ve hit upon one of the major reasons why they ditched triple, it replicates some of the gears so they become unnecessary. Unless you are after Strava segments, it’s not about how fast you climb but simply making it to the top without stopping or walking that measures your success! Personally, I’ve never used a screw-on block but what you state makes perfect sense. It’s much the same with pedals, the action of pedalling means that they should never come loose.
    All the best
    [email protected]

  10. Hi Colin,
    Thanks for taking the time to read the blog. If you are currently running a 31T inner ring with a 36t at the rear this is about as low as you can go. In fact, that combination already exceeds what Shimano recommend as being the maximum designed capacity of both the front and rear Ultegra Di2 derailleurs. The only option I can think of to provide you with lower gearing is to swap out the rear derailleur for a GRX Di2 model which would then allow you to fit an 11-42 ratio cassette. Though others may be able to suggest other possible options.
    Best Regards
    Team Ribble

  11. Hey Alan,

    thanks for the reply.

    My comment certainly wasn’t meant as a complaint, mind you. Quite the opposite really…I’ve been nothing but super happy with my ride for over 2 years now.
    As it was my first ride I never questioned it really and I still love the very smooth gear progressions. It was meant to be and it has proven great for my style of riding really.
    If you’re still curious have a look at order #145365344 though.

  12. Hi Ragnar,
    I’m very happy to hear that you love the bike so much. I was only interested to see if I could glean any information as to why the bike arrived with an 11-25 cassette and sadly I have not been able to.I t still seems slightly strange but as you have found the close gear progression of the 11-25 to your liking, then it has worked out very well indeed.
    Happy Cycling
    [email protected]

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