Do I need to declare modifications on my motorbike?
Yes. Any modification that changes your bike from its standard factory specification must be declared, or your insurer could refuse a claim or void your policy.
Which modifications matter
Insurers price cover based on the bike's risk profile, so changes to performance, appearance or security all need declaring, even if they were fitted by a previous owner.
- Performance mods such as aftermarket exhausts, tuning kits or big-bore conversions usually raise your premium.
- Cosmetic changes like custom paint, fairings or wheels can affect repair and theft costs.
- Security upgrades such as approved alarms, immobilisers or ground anchors may lower your premium.
Failing to declare a modification, even an honest oversight, can leave you uninsured when you need it most. Declare everything up front and compare quotes to see which broker treats your modified bike most fairly.
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What happens if I don't declare a mod?
Your insurer can reduce a payout, refuse a claim entirely, or cancel the policy, leaving you to cover costs yourself and possibly facing higher future premiums.
Do security devices really cut my premium?
They often can. Thatcham-approved alarms, immobilisers and trackers reduce theft risk, which many insurers reward with a lower price.
Should I declare mods made by the previous owner?
Yes. You insure the bike as it is now, so any existing modifications must be declared regardless of who fitted them.