Estimated reading time: 10 minutes
Table of Contents
- How to Measure Your Foot for Motorcycle Boots
- Motorcycle Boot Size Chart — EU to UK Conversion
- Do Motorcycle Boots Run Small?
- Motorcycle Boot Sizing Tips for UK Riders
- Sizing for Wide Feet
- How Closure Type Affects Fit
- Castiron Ride Model Sizing Comparison
- IronRider — Sizing & Fit
- ShiftCast — Sizing & Fit
- FAQ
- External Resources
How to Measure Your Foot for Motorcycle Boots
- Trace your foot on paper — stand on a sheet of paper and trace around your foot. Measure the distance from heel to the tip of your longest toe in centimetres.
- Measure foot width — measure across the widest point of the ball of your foot.
- Measure at end of day — feet swell throughout the day. Always measure in the evening and wear the socks you'll actually ride in.
Motorcycle Boot Size Chart — EU to UK Conversion
| EU Size | UK Size | US Men | US Women | Foot Length (cm) |
|---|---|---|---|---|
| 38 | 5 | 6 | 7.5 | 24.0 |
| 39 | 6 | 7 | 8.5 | 24.7 |
| 40 | 6.5 | 7.5 | 9 | 25.3 |
| 41 | 7 | 8 | 9.5 | 26.0 |
| 42 | 8 | 9 | 10.5 | 26.7 |
| 43 | 9 | 10 | 11.5 | 27.3 |
| 44 | 9.5 | 10.5 | 12 | 28.0 |
| 45 | 10.5 | 11.5 | 13 | 28.7 |
| 46 | 11 | 12 | 13.5 | 29.3 |
| 47 | 12 | 13 | 14 | 30.0 |
| 48 | 13 | 14 | 15 | 30.7 |
Do Motorcycle Boots Run Small?
| Boot Type | Typical Fit | Sizing Recommendation |
|---|---|---|
| Touring boots (IronRider) | True to size, roomy last | Size true — BOA adjusts for fine-tuning |
| Performance boots (ShiftCast) | True to size, roomy last | Size true — BOA adjusts for fine-tuning |
| Lifestyle shoes (RoadCast) | True to size, standard last | Size true — size up if wide feet |
| Street shoes (StreetCast) | True to size, standard last | Size true — size up if wide feet |
| Any boot with thick armour | Can feel snug initially | Allow break-in period of 2–4 rides |
Motorcycle Boot Sizing Tips for UK Riders
- Always measure both feet — most people have one foot slightly larger. Size to the larger foot.
- Measure at end of day — feet swell throughout the day.
- Wear your riding socks — thick socks add 0.5–1 size of volume.
- Check heel hold first — the heel should sit firmly with no lift.
- Allow for break-in — leather motorcycle boots typically need 2–4 rides to fully break in.
- BOA closure = more flexibility — BOA dial allows micro-adjustment after sizing.
Sizing for Wide Feet
| Situation | Recommendation | Best Castiron Ride Model |
|---|---|---|
| Wide feet, standard length | Size true, choose roomy last + BOA | IronRider or ShiftCast |
| Wide feet, between sizes | Size up half a size | IronRider or ShiftCast |
| Wide feet + thick socks | Size up half to full size | IronRider |
| Average width feet | Size true to EU chart | Any Castiron Ride model |
How Closure Type Affects Fit
| Closure Type | Fit Adjustability | Best For | Castiron Ride Models |
|---|---|---|---|
| BOA Dial | Micro-adjustable — highest flexibility | Wide feet, precise fit, all-day riding | IronRider, ShiftCast |
| Lace-up | Adjustable but fixed once tied | Standard width, traditional fit | MileCast |
| Velcro / Zip | Low adjustability | Quick on/off, standard width | RoadCast, StreetCast |
Castiron Ride Model Sizing Comparison
| Model | Last Width | Closure | Sizing | CE Rating |
|---|---|---|---|---|
| IronRider | Roomy / Wide | BOA Dial | True to size | CE Level 1 · 1 1 1 1 |
| ShiftCast | Roomy / Wide | BOA Dial | True to size | CE Level 1 · 1 1 1 1 |
| RoadCast | Standard | Velcro | True to size | CE Level 1 · 1 1 1 1 |
| StreetCast | Standard | Lace-up | True to size | CE Level 1 · 1 1 1 1 |
IronRider — Sizing & Fit

IronRider
The IronRider is built on a roomy last and sizes true to EU. The BOA dial closure allows micro-adjustment after sizing, making it the most forgiving fit in the Castiron Ride lineup for UK riders between sizes or with wide feet. CE Level 1 certified to EN 13634:2017.
- Last: Roomy / Wide
- Closure: BOA Dial
- Sizing: True to EU size — size up half if wide feet + thick socks
- Break-in: Minimal — BOA adjusts from day one
ShiftCast — Sizing & Fit

ShiftCast
The ShiftCast shares the same roomy last as the IronRider and sizes true to EU. BOA dial closure provides the same micro-adjustment flexibility. CE Level 1 certified to EN 13634:2017.
- Last: Roomy / Wide
- Closure: BOA Dial
- Sizing: True to EU size — size up half if wide feet + thick socks
- Break-in: Minimal — BOA adjusts from day one
Shop Castiron Ride — UK
FAQ
Do motorcycle boots run small in the UK?
Most motorcycle boots, including Castiron Ride, run true to your regular EU shoe size. Use the EU-to-UK conversion chart above. If you're between sizes or have wide feet, size up half a size.
Should I size up in motorcycle boots for UK riding?
Size up half a size if you have wide feet, plan to wear thick riding socks, or fall between EU sizes. BOA dial closure on the IronRider and ShiftCast allows fine-tuning after sizing.
How do I convert EU motorcycle boot sizes to UK?
Use the size chart above. As a general rule: EU size minus 33 = approximate UK size (e.g. EU 43 = UK 9).
Do motorcycle boots stretch with wear?
Leather motorcycle boots will stretch slightly during break-in — typically 2–4 rides. If a boot feels uncomfortably tight from day one, size up rather than relying on stretch.
What size motorcycle boots for wide feet in the UK?
Choose a boot built on a roomy last (IronRider or ShiftCast) and size true to EU. See our full motorcycle boots for wide feet UK guide.
External Resources
- GOV.UK — Motorcycle Protective Clothing
- IAM RoadSmart — Motorcycle Rider Safety
- Bennetts BikeSocial — Motorcycle Gear Reviews
- Visordown — UK Motorcycle News & Gear
- MCIA — UK Motorcycle Industry & Safety
More Castiron Ride guides for UK riders:
Written by T-K