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Free, tracked UK delivery on orders over £10

We offer free, tracked UK delivery on orders over £30, with delivery starting from £2.99 for orders below this value. We also have a selection of premium shipping options available including timed slots, Saturday delivery and DPD Pick-up

All of our bicycles are fully built by our experienced and certified mechanics prior to delivery; all you will need to do is turn the handlebars and fit some pedals.

Bicycles are shipped from a different warehouse to other items and so may arrive in advance of any other items you have ordered.

View all Delivery Options

90-Day UK Returns for all items

We want you to be 100% satisfied with your shopping experience at Rutland Cycling, so we offer a 90-day exchange or refund on any unused item (within the UK).

We've chosen to offer products at the very lowest prices, rather than provide a free returns service. If you do need to return an item, we provide printable postage labels and collection services at a small cost for all items - including bicycles.

See our full Returns policy.

30 Day Test Ride

All the convenience of buying online, without the risk
When you buy a new bike at full RRP from, you can now benefit from the added reassurance of our Rutland 30-day test ride. Once your new bike arrives, you can ride it as your own for 30 days, and we're confident you'll love it! However, if it's not right for you, we'll exchange it for another model. (There's a nominal charge of £60 for us to collect your bike - just make sure you keep the box your bike arrived in.)

On which bikes is the 30-day test ride available?
The Rutland 30-day test ride is available on all full price, non-discounted bikes available for home delivery on It is not available on discounted or special offer bikes, click and collect bikes, bikes bought on finance, bikes bought through Cyclescheme, or bikes bought in store. This offer is only available on bikes delivered to mainland UK addresses.

How many times can I use the 30-day test ride?
We will allow up to two exchanges within this scheme.

Full T's & C's

Finance your purchase

Get a confidential decision online in seconds.

At Rutland Cycling, we offer Finance on orders over £250, with 0% finance up to 36 months available on selected bikes, including some sale bikes. Visit the product page to see which finance products are available.

You can apply for Finance online or in store. To apply online, add your selected items to your basket, then checkout as normal. Select Finance as your payment method, fill in the application form, then complete your order.

See our Finance page for more information.

Lockdown Update: We are open

We are still despatching online orders and our sales team are on hand to help with any product enquiries you might have 7 days a week.
While most of our stores remain open for essential retail, we have updated our store policy.

Find out more>

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Helmet Size Guide

   Words by Harry Archer

   on 13/03/2018 13:43:35


Our helmet size guides below show you how to measure your head properly, to get the best fit.


How do I choose the right size?

1. Measure your head with a tape measure

Top tips: Ask a friend to help – it tends to improve accuracy. Keep the tape measure snug but not tight.


Measure around the centre of your forehead just above your ears, crossing the bumpy bone at the back of your head (occipital bone).

2. Find your size, using the tables below

Remember, all sizing information is a guide only. If you have any questions about bike sizing, our expert team is here to help. Call us on 0330 555 0080, use our Live Chat, or email us.

Helmets – Size Charts

See below for specific sizing charts for Specialized, Kask, Met and Giant

Specialized Helmet Size Charts

Adult 3-Size

Helmet Size Cir. (in) Cir. (cm)
Small 20"-22" 51-56cm
Medium 21.75"-23.25" 55-59cm
Large 23.25"-24.75" 59-63cm

Universal Adult Sizing

Model Cir. (in) Cir. (cm)
Max 22"-25.25" 56-64cm
Align 21.25"-24.5" 54-62cm
Chamonix 21.25"-24.5" 54-62cm
Centro 21.25"-24.5" 54-62cm
Sierra 19.75"-23" 50-58cm
Duet 19.75"-23" 50-58cm


Helmet Size Cir. (in) Cir. (cm)
Small 20"-22" 51-56cm
Medium 21.25"-23" 54-58cm
Large 22.5"-24" 57-61cm
X Large 23.25"-24.75" 59-63cm

Adult MIPS 3 Size

Helmet Size Cir. (in) Cir. (cm)
Small 20"-22" 51-56cm
Medium 21.25"-23.5" 54-59cm
Large 22.5"-24.75" 57-63cm

Universal MIPS Adult Sizing

Model Cir. (in) Cir. (cm)
Chamonix 21.25"-23.5" 54-59cm
Duet 19.75"-23" 50-58cm


Helmet Size Cir. (in) Cir. (cm)
X Small 18.5"-20.75" 47-53cm
Small 20.5"-22" 52-56cm
Medium 22"-23.5" 56-60cm
Large 23.5"-24.75" 60-63cm

S-Works TT

Helmet Size Cir. (in) Cir. (cm)
X Small/Small 20"-22.5" 51-57cm
Medium/Large 21.25"-23.5" 54-60cm

Dissident/Dissient Comp

Helmet Size Cir. (in) Cir. (cm)
Small 21.25"-21.75" 54-55cm
Medium 22"-22.5" 56-57cm
Large 22.5"-23.25" 58-59cm
X Large 23.5"-24.25" 60-62cm

Universal Fit Youth Sizing

Model Cir. (in) Cir. (cm)
Mio 17.5"-20" 46-51cm
Shuffle Child 19.75"-21.75" 50-55cm
Shuffle Youth 20.5"-22.5" 52-57cm
Flash 19.75"-23" 50-58cm

Small Fry

Helmet Size Cir. (in) Cir. (cm)
Toddler 17.5"-20.5" 44-52cm
Child 18.5"-21.75" 47-55cm

Kask Helmet Size Charts

Infinity / Rex / Rapido

Helmet Size Cir. (in) Cir. (cm)
Medium 20.5"-22.75" 52-58cm
Large 23.25"-24.5" 59-62cm

Protone / Valegro

Helmet Size Cir. (in) Cir. (cm)
Small 19.75"-23.1" 50-56cm
Medium 20.5"-22.75" 52-58cm
Large 23.25"-24.5"" 59-62cm

Bambino Pro / Mistral

Helmet Size Cir. (in) Cir. (cm)
Medium 21.75"-22.75" 55-58cm
Large 23.25"-24.5" 59-62cm


Helmet Size Cir. (in) Cir. (cm)
Small 18.25"-22.1" 48-56cm
Medium 18.75"-22.75" 52-58cm
Large 23.25"-24.5"" 59-62cm
X Large 23.75"-25.25" 63-64cm

Met Helmet Size Charts

MET Child Universal

Model Cir. (in) Cir. (cm)
Crackerjack 20.5"-22.5" 52-57cm
Elfo 18.25"-20.75" 46-53cm
Genio 20.5"-22.5" 52-57cm

Giant Helmet Size Charts

Adult Helmet Sizes

Helmet Size Cir. (in) Cir. (cm)
Small 20.25"-21.75" 51-55cm
Medium 21.75"-23.25" 55-59cm
Large 23.25"-24.75" 59-63cm


Helmet Size Cir. (in) Cir. (cm)
Small/Medium 19.25"-22.5" 49-57cm
Medium/Large 20.75"-24" 53-61cm

Holler Kids

Helmet Size Cir. (in) Cir. (cm)
One Size 18.25"-20.25" 46-51cm

Hoot Kids

Helmet Size Cir. (in) Cir. (cm)
One Size 19.75"-21.75" 50-55cm

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Rutland Cycling is a credit broker and is Authorised and Regulated by the Financial Conduct Authority (FRN 690345). Credit is provided by Hitachi Personal Finance, a trading style of Hitachi Capital (UK) PLC, authorised and regulated by the Financial Conduct Authority under Financial Services Register no. 704348. Credit is subject to status and affordability. Term & Conditions apply. The register can be accessed through