Buying Guides

You only get one head

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by Natalie Milne – Team GB and Team Scotland Triathlete

Recently I got a new mountain bike (Trek Fuel EX Project One) and as I got a new bike I thought it was only fair that I got some other bits of kit to complete the new package. I’ve never owned a mountain bike specific helmet and when I saw that Criterium had the new Bontrager Rally MIPS in the same colours as my bike I just had to buy it! Little did I know that when buying this helmet, I’d get to test out its level of protection a little sooner and in more dramatic style than I would have hoped!

Bontrager describe the Rally as raising the bar for comfort and protection in MTB helmets. The Rally has been around in Bontrager’s range for a couple of years now, but for 2017 has been updated with the MIPS Brain Protection System. I can say that when I tried the helmet on in the shop it felt and snug as a bug on my head. I’ve worn Bontrager road bike helmets for the past 3 years and found them to really suit my head shape, so when the time came to get a new mountain bike helmet Bontrager was the go-to brand for me to try.

The helmet has plenty of venting with deep channels that allow good airflow even at low speeds. The flat lock straps also help ensure the straps sit flush against your head and don’t get tangled. The design of the shell also gives greater coverage down the side and rear of the head for added protection. If you ever ride with goggles the adjustable visor is designed so as you can push it up out of the way to allow your goggles to sit neatly on the helmet (under the visor) when not in use. The headmaster fit system used on the Rally has a very fine degree of adjustment to help achieve a perfect fit. There is also enough space between the base of the helmet and the headmaster dial to allow a pony tail to slide through, which is a feature I have found lacking on other helmets in the past.

So, to the main event. Having been riding with the new helmet for all of an hour, I clipped my handlebar on a tree, resulting in me somersaulting over the bars and my head and shoulder taking a good whack. A landing hard enough to knock me unconscious and dislocate my shoulder. I daren’t think what might have happened to a lesser helmet judging by the damage sustained. In the end having endured an ambulance ride to A&E I was diagnosed with concussion to go along with my dislocated shoulder. Having learned in a slightly more painful and dramatic way than most, I know that I will certainly be paying even more attention to the quality of helmets (and other protective gear) I buy in future. After all you only get one head!

Check out the video from Trek that explains a bit more about MIPS and how it reduces the damaging risk of rotational forces on the brain in an impact.


A guide to Bike Lights (Part 1)

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It is the law to have your lights switched on your bike between the sunset and sunrise. But the choice is bewildering. In this Blog (Part 1), Criterium Cycles examines the technology behind lights and lighting, and suggests some ideas for how to choose the best light for your road or urban / commuting needs. Mountain Bike lights will be looked at in Part 2.

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Criterium Cycles Buying and Size Guides

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Criterium Cycles Buying and Size Guides

We know how confusing it can be to make the right choice when you are looking to buy something of a more technical nature. Sometimes it just isn’t possible to get down to the store and often, you are looking online when the store is closed anyway.

So we have developed a series of Buying and Size Guides for a range of products. As we develop more of them, we will add them to the list here so do keep looking back to see what new guides we’ve added.

If there is a specific buying or size guide you would like to see then Contact Us and let us know and we will be delighted to see what we can do.

Buying Guides


Size Guides



Bianchi Infinito CV

With bikes such as the gorgeous Bianchi Infinito CV it is always important to get professional and informative buying adviceg

Clothing Buying Guide

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Clothing for every (Cycling) occasion

There is a well known expression used in the outdoor industry. It goes “there’s no such thing as bad weather, just the wrong clothing”. Clearly whoever came up with that one was well versed in the variety of weather that we can experience in the UK. All four seasons in one day is another expression that also comes readily to mind. There is no doubt though that sitting on top of a bike for a reasonable length of time is going to expose you, the rider, to everything the British weather has to offer and more. So choosing appropriate clothing is important. Weather is not the only factor to be aware of either when considering clothing. Safety and comfort are two equally critical factors so in our Criterium Cycles Clothing Buying guide, we look at the most important factors to take account of when choosing your clothing.


Your layering strategy is the most important first step and the good news is it is pretty simple. You have three layers to consider

  • Base
  • Mid
  • Outer (or Shell)

You should then combine the layers depending on the season, the conditions and you. The last point is very important. Many of us here at Criterium Cycles never wear more than two layers. We prefer to be slightly colder and heat up through cycling than the other way round. We are all different and only you will know what works for you. However, the three layers are all quite distinct as we explain now.

Base layer

This is the layer that sits closest to your skin and is designed to do two things. First, it keeps you warm by acting as an insulator. Second it keeps you dry by wicking away the sweat. Wicking is the process by which a fabric draws moisture away by capillary action, thus keeping you dry. Base layers come in many types with different sleeve lengths, different fabrics, collars and weights. The trick is to find the one that suits your needs on any particular day / ride. Short sleeve for summer, perhaps long sleeve for winter. A short sleeve thermal base layer can always be supplemented by arm warmers and used in the Winter as well.

The other choice to make is in terms of material with the big difference being whether it is a natural or man-made fibre. The most common natural fibre is Merino Wool. It feels lovely to the touch, keeps you warm and it is less susceptible to retaining sweat odour than a man made fibre. This means you can use it for more than one ride before it needs a wash. It is not as good at wicking as a man made fibre so it will not dry as quickly if subjected to a rain shower. Man made / synthetic fibres are usually lighter, better at wicking and more flexible / stretchy. They are not though as warm as merino wool / natural fibres. Some companies also produce hybrid fabrics with wool / synthetic mixes or part wool / part synthetic for different parts of the base layer.

Everything is really down to personal choice. Check out the product descriptions, any customer reviews and technical info on each base layer for more information. Always remember to check the washing instructions that come provided with your purchase.

Mid layer

For many people, the Mid layer is the one that provides the most flexiblity. Mid layers include short or long sleeved riding jerseys, windproof gilets and Softshell Jackets. So depending on the weather and your own approach to keeping warm (or cool) Mid layers can either be the thing you wear on its own, or under a waterproof Outer layer / shell or even on top of a base layer. Whatever combination you choose, make sure you choose fabric that isn’t going to feel too rough and isn’t going be too heavy. Also, we like to suggest that if you are planning to use a softshell jacket or gilet as your top layer, it’s good to choose light coloured fabrics, possibly even with reflective characteristics. Remember – you’re likely to be a perfectly competent rider but it’s other road users we need to be aware of as well as help them be aware of us. Always best to be seen as much as you can.


Whatever you choose as your outer shell layer, it is really important that it is breathable, windproof and, if you are planning to use it when it’s raining, then waterproof and not just water resistant. There is a big difference. If your budget will stretch to it, then jackets that are really breathable but which will also stand up to everything the British weather can throw at them are likely to be the best all year round Outer Layers.


There are few things in cycling that are pretty much a requirement, but a decent pair of padded shorts is one of them. Check out our Saddle Buying Guide for a more detailed explanation of your sit bones and the contact points with the saddle. Note that the quality of the padding between your rear end and the saddle is going to make one heck of a difference to your cycling enjoyment. If you don’t want to be seen wearing lycra then fine. However, if you then wear something else over the top of your shorts do make sure they are cycling specific in terms of design and cut. Perhaps a pair of baggy cycling shorts for example. This is because seam design and location as well as panel design and fit is important for your comfort and enjoyment in the saddle. As with everything else though, there are different types and you get a lot of choice.

Close Fitting (basic) Shorts

There’s nothing basic about a good pair of shorts made of lycra but there are also some really good tips to note to get the best product:

Don’t wear underwear

Padded shorts are your underwear and are designed to be worn as the base layer. These days, microbial padding and inserts help enormously though we always have a clean pair for every ride.

Panels are important

The more panels the better will be the fit. 8 is pretty much the standard.


The padding or chamois in the shorts is a really important feature for your comfort. As the name suggests, they were initially of leather but these days tend to be synthetic materials. They often have gel filled inserts, to mould to your body.

Womens Specific Design

Plenty of Womens Specific Designs exists these days so there is no need at all to compromise with shape, fit or style.

Bib Shorts (and Bib Tights)

OK, so they can look a little bit like old fashioned braces but many cyclists do prefer them. This is because like braces, they keep the lower part of the garment in precisely the spot you need it kept all the time. There is also no seam to rub on your waist when bent over on the bars of your bike. Here are a few other good tips:


It is always best to judge the sizing of your bib shorts by bending over as if you were on your bike. It is advisable to do this in a changing room or somewhere a bit more private! However, the point is you will spend most of the time wearing your bib shorts in a bent over position on your bike. So the size / comfort balance you are aiming for is when you are in that bent over posture, not standing up.


Bib Shorts do come in padded and unpadded forms. We would always treat them exactly the same as normal shorts and go for the padded variety. However, make sure the specification of the product you are buying is exactly what you want i.e. padded or not. The unpadded version does mean you can wear a pair of padded shorts underneath if you wish.

Womens Specific Design

There are plenty of Womens Specific Designs for Bib shorts which have a different cut so as to fit over the chest more comfortably. Some manufactures such as Gore Bike Wear produce Womens Specific Designs that have zipping systems to make comfort breaks a lot more convenient.

Baggy Shorts

Baggy Shorts tend to be the preserve of mountain bikers. However, for those who really don’t like the look of lycra, even if they wear it, they can have a pair baggy shorts over the top to ‘tone down’ the look! If you think baggy shorts may be the way to go, here are some additional tips:


It is still worth looking at high quality breathable and windstopper fabrics. This is especially true if you are going to be wearing them over other tighter fitting garments. You want to make sure you don’t overheat.


If your budget will stretch to it, then it is definitely worth looking for baggy shorts that come with a removable liner, padded or otherwise. This helps enormously when wearing baggy shorts over the top of other shorts.

Fit & Cut

It is worth buying cycle specific baggy shorts because they will normally come with a higher waistband at the rear. You don’t want to inadvertently expose things you would rather not expose. They should also have reinforced padding on the seat to reduce wear.


A Jersey is just a fancy name for a cycling top. They come in all kinds of sizes and materials. When choosing one, your key concerns should be durability, lightness, comfort and the wicking capacity of the fabric. Wicking is the ability of the fabric to draw out moisture using capillary action thus drying out the fabric quickly principally from sweating. Jerseys are a mid layer but can be worn as your outermost garment depending on how you choose to manage your layers. Jerseys may be your innermost garment on occasions which is why comfort is an important consideration.

In terms of material, the wicking capability is important so synthetic fabrics tend to be very popular such as polyester. Polyester has the benefit of being very light and feels quite comfortable too. If you are a traditionalist, or just like the feel of it, then wool is good. Do make sure you go for Merino wool which is much lighter than normal wool, has good wicking capability and dries fast. It also has antibacterial properties, more so than polyester. That means you won’t be quite as smelly after just one ride. We wouldn’t suggest leaving it for too many rides though!

Short Sleeve

Good for the summer when you want to keep cool. If it does get cool and you get caught out, then arm warmers are always an optional extra worth considering.

Long Sleeve

The preferred choice in the winter. However, because of this they come in a bewildering range of weights and thickness with the heaviest, most insulated being very warm indeed. If you are the kind of person that gets very hot on a ride, you may find this overbearing so always check out the specific product descriptions.

Arm Warmers

We absolutely love arm warmers at Criterium Cycles. They are a really clever and flexible addition to your wardrobe. They enable you to add a section of warm clothing to a short sleeve jersey for instance without the hassle of having to take it off and replace with a long sleeve jersey or jacket. They can be quite a challenge to make however. The manufacturer is always trying to strike a balance between an arm warmer that won’t keep slipping down yet isn’t too tight so as to bite into the arm. We have selected arm warmers carefully at Criterium Cycles and the brands we sell are the ones where we think the manufactures have got that balance just right.


Gloves are similar to cycle shorts in our opinion – they are an absolute must. They perform a wide range of functions from general comfort, anti-vibration padding and insulation.


If you spend a decent amount of time in the saddle then inevitably your palms are going to rub against the bar tape or grips on your handlebars and suffer mild abrasion from constant changing of gears. This is especially true if you live where the Criterium Cycles Team lives.

Vibration Cancelling

Then there’s the vibration coming through into the handlebars. Even if you have a high tech vibration cancelling frame such as on the Trek Domane SLR or the Bianchi Infinito CV you are still going to feel the input from our wonderful British Tarmac.

Weather proofing

And then there is the weather. Your fingers are going to get cold because they are at the ends of your body. They are your first point of contact between the onrushing wind and rain. They deserve to be wrapped up a bit.

Safety first

Finally, there is safety. We really hope you don’t come off your bike but it is inevitable that will happen once in a while. The last thing you want is the skin on your hands coming into contact with whatever surface you land on. So for all those reasons, gloves are definitely worth having.

Long or Short?

If cycling in winter, go for long fingered gloves. Many additional options are possible including waterproof gloves, breathable gloves, thermal gloves or various combinations. If it is going to be really cold, make sure you have long cuffs. You can tuck them under the end of the sleeve of your cycling jersey to make sure the wind and rain can’t get in.

If it is the summer and comfort and padding are you priorities, then short fingered mitts may well be the thing. They are certainly more breathable but they are not quite so good if you find your hand coming into contact with the ground. However, we are sure you will find plenty of ways to make sure that doesn’t happen in any event!

For mountain biking, we tend to go for long fingered gloves most times. This is partly for protection and partly because you are going to be braking and changing gear pretty regularly. So the added protection against abrasion is worth having.


Socks are an essential part of a cyclist’s wardrobe. Close fitting socks are good for ensuring that close fitting shoes (e.g. road cycling shoes) don’t rub. There is little more guaranteed to spoil an otherwise enjoyable ride than a blister. In the summer, lightweight socks are best especially those that have good sweat and moisture wicking capability. In winter, thicker, more insulating socks are best. Your feet, like your hands, are body extremities that tend to feel the cold the most. We in Criterium Cycles certainly subscribe to that view.

Helmet Buying Guide

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Helmet Buying Guide

A bike helmet is designed for one primary purpose, to protect your head from injury in the case of accident. Whilst it is not a legal requirement in the UK to wear a helmet at all times, it is advised and we recommend you wear a helmet at all times you are cycling. You can replace the bike but you definitely only get one head. Beyond the basic function of protection from injury, helmets are then designed with other critical functions in mind. These include comfort, ventilation and aerodynamics. Some of the technologies employed in helmet design are genuinely leading edge.  Plus, it’s a fast moving world so it is important to make sure you are buying the helmet suitable for the type of riding you are going to be doing.

The good news is that Criterium Cycles sells a wide range of helmet styles and types from some of the world’s leading brands. So whatever kind of riding you are planning and whatever your budget, we will have the helmet for you. Check out some of the most important factors to be taken into consideration using this Criterium Cycle Helmet Buying Guide.


When you are considering a new helmet, you may wish to consider that one of the challenges with traditional helmets is that they are not fully effective in protecting you from angled impacts. Angled impacts can cause violent accelerations leading to increased rotational forces on the brain. This can lead to diffuse axonal injury, one of the major causes of unconsciousness and in some cases, permanent brain damage. There is however a technology that has been shown to address this issue with considerable success. It’s called MIPS (Multi-directional Impact Protection System). You can read our detailed blog on helmets and MIPS by clicking here.

MIPS is designed to mimic the brain’s own system for protecting itself from trauma. MIPS provides a liner, separate from the shell of the helmet but connected by a low friction layer. When a MIPS helmet is subject to impact, the low friction layer allows the helmet to slide relative to the head. The result is a helmet which reduces rotational acceleration on the brain by nearly 40% without impacting adversely on the energy-absorbing properties of the helmet overall.

Helmet Fit

If the most important priority is to have a helmet in the first place, the next most important thing is to have one that fits properly. This is really important for your safety. If the helmet is moving about on your head it is not protecting you as it should. It will then prove a real distraction, itself a safety concern.

To measure your head correctly, you will need a measuring tape (and possibly a friend or colleague to help!). Measure the circumference of your head by measuring horizontally around your forehead. Do this roughly 1 inch (2.5cm) above your eyebrows. Make sure you keep the tape measure both level and a close fit. Make sure as well that you stay above your ears which helps keep the tape measure level. We often find that taking three measurements and then the average of the 3 helps remove any measuring error in one.

Some manufacturers produce womens’ specific designed helmets which often have a slightly different internal sizing. On our website, you will see those helmets that are specifically designed for women in the product description.

Natalie Milne demonstrating a correctly fitted cycle helmetThis picture of Natalie Milne, the Team GB Triathlete sponsored by Criterium Cycles, demonstrates a well fitted helmet. The straps should form a v-shape with the internal angle of the V just below the ear. If correctly fitted, you should only be able to fit two fingers between your chin and the chin strap. More than that, and it’s too loose. It should feel close fitting but not uncomfortable or biting into your chin.

Helmet Types


Whilst designed primarily for road cycling, these helmets can really be used for all types of cycling. This means they are a good, all round solution. Some helmets come with advanced internal mounting systems that ensure a constant fit around the head. Others focus on lightness and aerodynamic performance. Within the product description for each helmet you will be able to find a summary of the technical features.


Mountain Bike helmets tend to focus less on lightweight / aerodynamic performance (though that is still important) and more on protection recognizing the challenges of trail and off road riding. Peaks on the front are usual features and some helmets come with full face protection. This ensures the lower jaw / chin area receives optimum protection.

Urban Commuter

These helmets are specifically designed for use in the city / urban environment. They tend to do without many of the ventilation systems of more advanced road and mountain bike helmets. This is because they tend to be used for shorter, less physically demanding rides. However, the focus is still very much on safety and protection.


It is really important to get kids to start wearing a helmet at the earliest age possible as it teaches good habits! We stock a wide range of kids’ helmets in some pretty wild colour schemes so that they can look really cool as well as stay safe.

Shoe Buying Guide

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Shoe Buying Guide

Cycling shoes come in a multitude of styles and designs with many of the designs being specific to the riding for which the shoe is going to be used. It is always worth first considering exactly what the shoe is going to be used for and selecting accordingly and then ensuring you have a comfortable, snug fit. Finally, what the shoe looks like is important in our fashion conscious world, but it’s not as important as ensuring you have the right shoe for the right job and it that it fits properly. In our shoe buying guide we explain the key factors to take into account as well as the differences between different brands.

Types of Shoe

Cycling shoes can be split into two very distinct groups – Clipless and Non-Clipless.


The term ‘clipless’ confuses many people because the word clipless derives from the fact that you can dispense with those slightly terrifying toe clips or straps and simply ‘clip in’ to a cleat binding system that locks the sole of the shoe to the pedal. At first it probably sounds a bit mad to be locked to the pedal and we totally accept it takes a little bit of getting used to.

However, it is worth it because there are very good reasons for clipping in. First, it’s very efficient. The faster you turn the pedal (cadence) the harder it is to keep an unattached shoe on the pedal whereas it’s pretty straightforward when you’re clipped in. You do want to increase cadence by the way because higher cadences are essential for efficient pedalling. Second, it’s really comfortable. Riding a bike on flat pedals means your feet tend to move around a lot whereas if they are attached via a cleat, they stay in one place. This is good news for all those tasks you will need to focus on (handling, climbing, descending) without being distracted by whether your feet are staying on the pedals as well.

If you do opt for Clipless then it is really important to make sure your pedals are compatible with Clipless shoes.

Non Clipless

These shoes are much more like traditional shoes though with design features that make them far more suitable for riding a bike than wearing your favourite pair of worn out trainers. Some Mountain Bikers prefer not to be clipped into a pedal for technical descending and cornering. Used in conjunction with a large platform pedal and a high grip sole on the shoe, the foot can be lifted off the pedal and used for balance but then quickly reapplied for pedalling.

Types of Cleat

Road Bike Cleats

Road Bikes utilise three bolt cleat systems such as Shimano SPD-SL, Speedplay and Look. The cleat stands proud of the sole of the shoe making it pretty difficult to walk (in fact, we don’t recommend trying too to walk too much in them) but they do give the best platform for delivering the most efficient pedalling action.

It is particularly important with road bike cleats to fit them correctly and ensure they are properly aligned and set. In particular, it is important that the centreline of your cleat is at least 1cm behind the 1st metatarsal head for fore and aft alignment. If you don’t do this, you will find the nerves in your feet (of which you have plenty) suffer undue pressure and become sore, reducing your pedalling efficiency and increasing your discomfort.

Mountain Bike Cleats

These are two bolt systems such as Shimano SPD and Crank Brothers. They have cleats that are recessed into the tread pattern making it easier to walk over tricky terrain. Set up of mountain bike cleats is equally important to get right as for road, offering the same fore and aft and toe in / toe in positioning.

How to Select the right Shoe Size

Shoe Sizing can be a bit of a challenge not only because there are so many systems in use around the world, but also because manufactures often take a different approach from each other in how they interpret sizing systems. Shoes are manufactured from moulds or ‘lasts’ which is the sole shaped template from which the shoe is made. The size of the last takes no account of manufacturing tolerances nor does it guarantee to result in a shoe size that is guaranteed to fit a particularly foot size.

In the UK for instance, we use a system that calculates an adult shoe size using the following formula:

Adult shoe size = (3 x last length in inches) – 25

So the last length may be slightly variable and different manufacturers may use a different constant (the 25) to calculate the actual shoe size. Confused? Well it is a bit which is why we have produced the following table to help convert the various sizes. However, it is definitely for guidance only – we can’t guarantee the conversion. What we have done though is add a few helpful hints underneath the tables, both general as well as for the shoe brands themselves, to help make the choice as informed as possible.

Mens Shoe Sizing

Mens Shoe Sizing Guide Table

Womens Shoe Sizing

Womens Shoe Sizing Guide Table

General Tips


The Mondopoint measurement in mm is the nearest thing the shoe world has to an international standard. It measures the distance between your heel and the end of the toe that protrudes the most, usually your big toe. Make sure you stand against a wall or similar and measure to the end of your big toe but along a line that is perpendicular to the wall.

Carbon Soled Shoes

Some cycling shoes in the Criterium Cycles shop have carbon soles or part carbon soles. These are very easily scuffed or scratched and if you do that by mistake, we won’t be able to accept the shoes back even if you haven’t worn them riding out on the bike. So when checking to see whether the carbon soled shoes you have purchased fit you properly, it is always a good idea to do it when stood on smooth carpet or similar so the sole of the shoe remains in pristine condition.

Brand Specific Tips


SiDi hand builds its shoes from 3 ‘lasts’ or moulds – Standard Men’s , Women’s and Mega (wide fit). Traditionally, the shape of SiDi shoes provide feet with a ‘snug’ toe area. SiDi call this Pro Fit which means the toe will be close to the end of the shoe and the shoe itself will be snug fitting around the whole foot. The focus of the SiDi shoe design is therefore to provide riders with shoes that do not move once they are on your foot.

For people with wider feet and / or higher arches, SiDi has designed the Mega size for every standard shoe size. The SiDi Mega size provides about 0.5 cms extra width along the axis where the foot is at its broadest.

As a rule, however, because the shoes are snug fitting from heel to toe, we tend to find going up an EU size from what you would normally wear makes sense.

Bontrager Logo

We tend to find that Bontrager cycling shoes follow EU sizing pretty accurately and with reasonably generous fit parameters. However, you also have the benefit of the Bontrager 30-day Unconditional Guarantee. This means that if you buy them but don’t love them you can send them back, guaranteed, and exchange them for another pair of Bontrager shoes.

ShimanoA bit like SiDi, our experience has been that Shimano shoes are normally a size up from the EU size. So for example, if your normal shoe size is EU40, then you may find Shimano EU 41 will be a more appropriate fit.

Lights Buying Guide

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Lights Buying Guide

In the Criterium Cycles Lights Buying Guide, we set out the key points to be taken into consideration when buying any lights for your bikes. We start with the two rules to consider before look at the many options that are available.

Obey the Law

It is the law in the UK that between the hours of sunset and sunrise, you must be displaying at least one white light at the front and one red light at the rear plus have a reflector at each end of your bike and on your pedals. Watch out for the reflector bit – that catches many people out!

Lights are always good

It is never against the law to have lights on your bike during the daytime so we always advise having daytime running lights if you can. They will make a big difference to your safety and well being when out on our roads.

Check out this video of President of Trek Bicycle, John Burke, explaining why daylight visibility is so important and advantageous.

How to measure brightness

The power of a cycle light is measured in Lumens so it goes without saying that a 1000 Lumen light (which is extremely bright by the way!) is considerably brighter than a 100 Lumen light. The Lumens scale is linear so 200 Lumens is twice as bright as 100 Lumens. However, it is worth noting that the human eye can be deceived by a number of factors so be aware of these when considering cycle lights.

How much more light does it take to be noticeable?

A 120 Lumen light is going to look pretty much the same as a 100 Lumen light to the human eye. As a very general rule of thumb, all other factors being equal, Light B needs to be approximately twice the power of Light A in order for Light B to be noticeably brighter to the human eye.

Is focus important?

Yes it is. Just as when you use a garden hose and make the nozzle small the jet becomes much more concentrated even though you haven’t turned the water tap at all, exactly the same applies with light. A focused beam will be brighter than an unfocused one.

Does strobing or interruption work?

It most certainly does. Bontrager for instance have done a great deal of research into this and discovered that with their Ion and Flare lights, the interruption of the light (into a mild strobe effect) causes motorists to be far more aware of cyclists and give them much more room when passing.

Bike Pump Buying Guide

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Bike Pump Buying Guide

Tyre pressure is a remarkably important variable than impacts not only general safety but also handling / grip as well as comfort over longer distances. Whatever tyre pressure you choose to inflate your tyres to, you do need to keep pressure checked regularly (bikes can lose considerable pressure if left idle even for a relatively short period time) and you also need to make sure you can inflate them whilst out riding with the minimum of fuss. Discover how to make sure you have the right bike pump for the job using our Criterium Cycles Bike Pump Buying Guide.

Types of Pump

We would advise all cyclists to consider having at least two pumps to hand; a track pump for use at home (fast, accurate inflation) and a mini pump of some description for use out riding (lightweight, portable and still very effective if not as quick or accurate as a Track Pump).

Track Pump

Specifically designed for accurate, rapid inflation, track pumps stand on the floor and have handy feet incorporated into the design of the base on which you can rest your feet and gain more purchase when pumping the tyre. They come with a handy pressure gauge so you can see exactly what pressure you are delivering and are perfect for use at home. The downside is they are too large to carry with you on the ride so you need another solution for that.

Hand / Mini Pump

We have to be honest – they are nowhere near as quick or as effective as a Track Pump. But they will fit in your saddlebag or seat pack and they will make sure that if you have a puncture, you can get enough air in the tyre to get home though be prepared to have to pump a lot of strokes and also be prepared for a little guesswork too as they don’t usually come with gauges.

CO2 Pump

A brilliant little invention, they take out the hassle of having to pump a large number of strokes to inflate a tyre. One canister will get an empty tyre to around 80 – 90 psi and very quickly so enough to get you home and we even stock some CO2 pumps that have a little gauge on so you don’t have to guess. Read the instructions carefully though – CO2 canisters are under considerable pressure so they get exceptionally cold when discharging and if not used correctly can cause injury. There’s no need to be afraid of them, just learn how to use it and treat with respect.

Another little tip with CO2: Because the molecular structure of CO2 is smaller than air, you may find your tyre inflated by CO2 will have completely deflated within a couple of days. Don’t panic – it’s almost certainly not another puncture – just try re-inflating with air.

Tyre Buying Guide

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Tyre Buying Guide

As with tyres on cars, tyres on bicycles are crucial for safety, reliability and comfort. And as with car tyres, different tread patterns are needed for different applications. The trend for increasingly wider tyres meaning that the choices are becoming bewildering. However, there are a few basic things you need to know that will help you easily navigate the complex world of cycle rubber.

Size is important

As with frame sizing, wheels on road bikes are measured in cm and on mountain bikes they are measured in inches. Just to add to the challenge, Hybrids have frame sizes usually measured in inches but they have tyres and wheels measured in cm. It is therefore crucially important to know how to check your wheel and tyre size. Don’t forget though that your frame will also dictate how large a tyre you can have. If you have a hybrid bike or a road bike fitted with cantilever brakes and mudguards, chances are you going to be restricted in what you can fit with respect to your tyres. Always check the specification of your particular bike before upgrading your tyre size.

Wheel Size

Check the sidewall of your tyre. You will find the size of the tyre clearly printed. If it says 700 x 25c then you have a 700mm wheel with a tyre that is 25mm wide. Note, even the 700mm is slightly approximate due to some tyre manufacturers having slightly taller or shorter sidewalls. Note also that on a mountain bike, you are going to have a wheel measured in inches. This will either be 26”, 27.5” (also known as 650b) and 29” (29er).

Road Tyre Size

Not so long ago, pretty much every road tyre was 700c x 23c and that made life fairly simple. Not so any more. Now, 25c, 28c and even 32c are increasingly common. Why is this? The tyre manufactures say a wider tyre reduces rolling resistance and therefore saves energy plus they are more comfortable. It seems the frame manufacturers agree because frames are becoming ever more generous in their clearances to accept these bigger tyres. Not everyone agrees because there are some potential aerodynamic and weight disadvantages of wider tyres to be taken into account. But the trend is clear – the pros are using wider tyres and that inevitably means the bike manufacturers will follow suit.

Mountain Bike Tyre Size

Mountain bike tyres also come in a variety of widths including Fat Bike tyres and Plus Bike tyres. Tread patterns also play a significant role with mountain bike tyres. The type of terrain you will be predominantly riding over will to a large extent dictate the tread pattern best suited to your needs. If your focus is Cross Country, then a lower profile tyre will probably suit best. These are good on hard pack surfaces with a lower rolling resistance. However, the smaller knobs on the tread pattern will get overwhelmed more quickly in deeper mud than a tyre with a larger, deeper tread knob pattern. If your focus is Downhill, then the larger tread knobs on both the centre tread and the side tread areas will ensure the tyre bites in really well with excellent braking performance and excellent grip in turns.

The really critical things though when choosing mountain bike tyres are:

  1. Correct Wheel Diameter
  2. Width (there needs to be sufficient room to get your tyre between the forks / brakes / stays)

Fat Bikes

Fat Bikes initially became popular for riding on snow and really loose material, providing plenty of grip even in the most extreme conditions. However, the fashion for Fat Bikes has really taken off with Fat Bikes an increasingly common sight at trail centres around the country. Pedalling from a standing start and getting up to speed can require a bit more effort than a more traditional trail bike and the feedback is slightly less with the big fat, lower pressure tyres absorbing much of the undulations in the trail. But get a fat bike up to speed downhill and it’s 100% maximum fun. You’ll flow through those berms like never before with a smile nearly as wide as the tread on the tyre.

Plus Bikes

The most recent addition to the mountain bike tyre glossary is the Plus Bike. In principle they offer the ability to run wider tyres (e.g. 3.0 inch) over standard (2.3 inch) on a wider rim (typically 40mm wide compared to 25mm). Thus a 27.5+ tyre ought to give similar benefits to a 29er in terms of rolling radius with greater tyre contact patch and therefore grip. The wider and deeper tyre also can run lower tyre pressures thereby giving a more confident and compliant ride. Customer feedback has been overwhelmingly positive.

Beads – Folding or Rigid

The bead of the tyre is the stiff edge of the tyre, usually made of steel or composite, that hooks onto the rim to keep the tyre firmly seated on the rim of the wheel.  Two options are available:


They are less flexible meaning they can be a pain to carry around or store. They do however tend to be a bit cheaper.


The advantages of being light and easy to store however does come with a price penalty compared to rigid beads.

Valves – Presta or Schrader

The valve of the tyre is where you attach your pump to get into the tyre to inflate it. Valves come in one of two types:


These valves are tougher and more reliable. Schrader valves are similar in design to those you will find on your car. Amongst their advantages are that they are extremely resilient and are really difficult to break plus you can remove the inner core if something does go wrong and replace it. The downside of them is that partly because of this inner core, they are wider and therefore require a larger hole through the rim of the wheel. That’s not very good because holes in the rim are one of the principle causes of weakness of the wheel. Tyres can also be slightly harder to inflate when they have Schrader valves because of the need to activate the spring on the inner core of the valve.


Presta valves on the other hand are narrower and easier to inflate, not least because you do not have to deal with any spring on the inner pat of the valve. However, because they are narrower, they are more delicate and if you damage the valve, you can’t always replace it – you may have to throw away not only the valve but the inner tube as well.

The whole question of whether to go Schrader v Presta is something of a moot point however. If you have a road bike then you will almost certainly have Presta valves but if you have a Mountain Bike, you will have a choice of either. However, it will be rim specific. In an emergency, you can always get a presta valve through a rim hole designed for Schrader valves but not the other way round.

The most important thing? Buy a track pump that has a valve attachment that will work with both thereby rendering it pretty irrelevant whether you have a mixture of the two valves. Do note however, that if you have a wheel rim that has a deep dish (perhaps a carbon dish such as a Bontrager Aura wheel) you will need to buy an inner tube that has a long valve otherwise it may not be long enough to sit inside the carbon dish and still protrude far enough for you to be able to attach a pump and inflate the tyre.

Tyre Pressures

Pressure is measured in good old fashioned imperial psi (pounds per square inch) on bikes. Each tyre will have its own minimum and maximum recommended tyre pressures and it is important to ensure you stay within these parameters when inflating your tyres.

In terms of which Tyre pressure also dramatically affects grip and comfort as well as puncture prevention and rolling resistance. For example, if a road tyre has a minimum of 80 psi and a maximum of 120psi, if a rider of 90kg riding on rough tarmac inflates the tyre to the minimum 80psi then the rolling resistance and risk of pinch puncturing will be materially higher. However, if the same rider on the same road inflates the tyre to the maximum 120 psi then the tyre will feel significantly easier to reach and maintain a higher speed. But the vibrations felt through the bike also be significantly higher.

In summary, tyre pressure is a constantly evolving process based on a balance of your weight, comfort requirements and performance. We recommend starting with the mid point between the minimum and maximum pressures of your tyre and increase or decrease the pressure by 5 psi increments / decrements until your own ‘sweet spot’ of comfort / grip is achieved,