WATCH YOUR TYRE TREAD
The legal limit of tyre tread depth in the UK for motorcycles over 50 cc is 1 mm across ¾ of the width of the tread pattern and with visible tread on the remaining ¼. For motorcycles up to 50cc the law requires that all the grooves of the original tread pattern must be clearly visible. The legal requirements may differ in other countries.
Tyre treads are designed to give good wet grip but the road surface also plays a significant role in tyre to road adhesion. In general, wet grip decreases as tyre tread patterns wear down and as the depth of surface water increases. Riders should take this into consideration and reduce speed in wet conditions. Motorcycle tyres normally have tread wear indicators in the tread grooves and as these are approached, you should consider a replacement. Once the indicators are level with the tread surface the tyre should be replaced.
The correct inflation pressure is vitally important for safe handling of motorcycles. The recommended pressure for original equipment tyres will be stated in the motorcycle owner's manual. For the fitment of aftermarket alternatives, advice should be sought from the tyre specialist or the tyre manufacturer. Specific advice from the tyre manufacturer is recommended for tyres fitted to classic and vintage motorcycles (pre-1960) where pressures quoted in the original handbook may be inappropriate.
Pressures must be adjusted appropriately for solo and for pillion and pannier loads. It is dangerous to re-inflate a tyre which has been run flat or seriously underinflated. Such tyres should be removed for inspection by a tyre specialist. Prolonged under-inflation causes excessive flexing, deterioration of the casing and rapid wear of the tread edges. Your fuel consumption may also be adversely affected.
Over-inflation may result in an uncomfortable ride, a reduced area of contact with the road, accelerated wear on the tread centre and makes the tyre more susceptible to impact damage. Inflation pressures should be checked once a week when the tyres are cold using an accurate and reliable pressure gauge.
SAFETY AND MAINTENANCE
Motorcyclists are strongly encouraged to be aware of their tyres' visual condition such as tread depth, cracking of the tread or sidewall rubber, cuts or bulges, foreign objects, as well as being alert to any change in dynamic performance or behaviour such as air loss, noise or vibration.
Driving over potholes, kerbs and speed bumps, even at low speeds can result in the weakening or fracture of the tyre structure.
Riders experiencing an in-service impact should ensure immediate inspection by a tyre professional. Lumps and bulges can indicate internal damage and should be examined by a tyre specialist without delay.
Inflation pressures must be checked at least once a week. They should be checked only when the tyre is cold - this is due to an increase in pressure when the tyre is warm after being used. Therefore, a reliable pressure gauge should be used.
The recommended inflation pressures are vitally important for safe handling of the motorcycle. Pressures must be adjusted appropriately for solo and for pillion and pannier loads. It is dangerous to re-inflate a tyre which has been run flat or seriously under-inflated. Such tyres should be removed for inspection by a tyre specialist.
Tyres should be examined regularly, removing stones and other objects embedded in the tyre. Oil or grease should be removed with a suitable diluted detergent.
Lumps or bulges could indicate internal damage and should be examined by a tyre specialist without delay.
Tyres can deteriorate with age which shows as cracking of the tread and sidewall rubber, sometimes accompanied by carcass deformation. Cracking is usually an indication that tyres have been in service for an extremely long time, but rubber deterioration may be brought about by poor storage conditions. If cracking is severe, the tyre must be replaced.