Do I need an MOT for my
classic bike?

AJS | Ariel | BSA | Norton | Matchless | Sunbeam | Triumph | Velocette

The forty year rule

If your motorcycle is 40 years old or more, and if it hasn't been substantially modified, it doesn't require an MOT.

MOT testing station logo "Substantially modified" is a woefully loose term and basically means that if the engine has been upgraded with a turbo charger or some other performance aid, or if the frame/wheels/fork have been significantly altered, an MOT will be required.

Smaller changes like slightly wider wheel rims, or custom saddles, or different indicators, or a change in colour might not make a difference. The basic principle is: does the Triumph or Honda or Harley-Davidson look/feel/ride/behave very differently to the way it left the factory?

But who decides? Well that's a tricky one because there are so many variables. Ultimately, the problem might not come to light unless and until the bike becomes involved in an accident or theft where the police and/or insurance company gets involved. It's then that the vehicle's documents and status will be checked, and it's then that someone will decide if your bike has fallen foul of the MOT regulations.

Does a bigger engine automatically mean that the bike has been substantially modified?

Well it might. If you stick a V8 motor in a Tiger Cub, that's definitely considered "modified" and will mean an MOT tester will be required each year to check the bike. But if you upgrade a 350cc British single to a 500cc single, that might be considered acceptable—and especially so if you use original manufacturer parts.

So a 500cc BSA M20 upgraded to a 600cc M21 might be within the rules. Similarly, upgrading a 650cc Triumph Bonneville to a 750cc Triumph Bonneville might be fine. It depends on how severely the rules are interpreted at any given time, by any given person or "expert".

Unsatisfied with this position? Well so are we. It's worryingly ambiguous. But that's the situation, and sometimes you have to take things as you find them. Meanwhile, if you have any doubts about the legality of your motorcycle, MOT-wise, we suggest you take it to an MOT station and ask if those ape-hangers, big bore kit, or high-level pipes or that chromed and twisted steel girder fork has substantially modified your wheels.

MOT rules & regulations

Keep in mind however that although the MOT tester might have a better idea of the rules and regulations than yourself, he or she also has to make a reasonable judgement—meaning that they could be right or wrong. But either way, we think you'd be wise to tell your insurance company about any significant changes to your bike. Your broker might add a charge to your premium, or they might not. But if they feel that you've failed to tell them something significant about the motorcycle, and if it's stolen or involved in a crash or similar, they might refuse to pay—in which case you'll lose money, or will have to take the insurance company to court. Tip: Avoid litigation whenever possible. It's expensive and stressful.

Rolling 40 year rule

Note too that the 40 year rule is "rolling". Therefore, if your bike is 39 years old at the moment, it will need an MOT. But next year, if you've kept it reasonably standard, it won't need an MOT. So any contemporary bike from Honda, Yamaha, Suzuki, Kawasaki, BMW, Triumph or whoever will eventually become "MOT-free"—unless, that is, there's another rule change coming at us.

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