EU43 motorcycle boots can be a starting point for replacing a well-used pair, but a worn boot is not a perfect sizing template. Check the new model, your current measurements and the way the fresh lining and closures hold your foot.
Check the UK label
RST's men's chart lists EU43 as UK9, matching this collection heading. TCX's adult chart lists EU43 as UK8.5. Use the exact maker's guidance and confirm the product option rather than assuming the two systems always translate identically.
Compare new with worn
Bring your old boots as a reference for what worked and what did not. Note whether the heel slipped, the toes felt restricted or a closure reached the end of its adjustment. Those observations help you compare a replacement without expecting it to reproduce a worn-in shape immediately.
Allow for your normal equipment
Fit the new boots with the socks and any insoles you normally use, where compatible with the manufacturer's instructions. Check that they can be secured properly and do not crowd the foot. Persistent pressure should be investigated rather than dismissed as something that must disappear with wear.
Compare your options at Moto Central
Bring your old EU43 boots and normal riding socks to Moto Central for a practical replacement fitting.
