Motorsport Tyre Tips

SELECTION

A large selection of tyres is available to suit all types of motorsport competition BEFORE selecting your wheels, establish the best tyres for your car or area of sport. Widest and softest is not always the most suitable Discuss the best option with one of our motorsport distributors (link)For motorcycle racing tyres contact your state motorcycle tyre distributor (link)

FITTING

FITTING SHOULD ONLY BE CARRIED OUT BY SUITABLY QUALIFIED PEOPLE Check wheel width and diameter are correct for tyre size being fitted Check for Drive 'arrows' or if tyres are directional they must be fitted the right way Avoid damage to the bead area Ensure alloy wheels are not porous. (This is less of a problem with modern alloys) Follow ALL Safety procedures for bead seating and inflation

TYRE CARE

Store tyres in a cool and dark environment Avoid high temperatures, direct sunlight, and electric motors and welding equipment which are a source of ozone. Clean off any contamination from fuel or oil immediately New tyre life will be improved if tyres are correctly 'scrubbed in'

TYRE MARKINGS

Size markings on circuit racing tyres indicate approximate dimensions e.g. 240/625R17 where: Where 240 is nominal tread width (mm), 625 is overall diameter (mm) 17 is the wheel diameter in inches

NOTES

Other manufacturers may use different markings.Other markings indicate compound, casing construction and, if applicable, a pattern designation Tarmac rally tyres and Gravel rally tyres are usually size marked as per passenger car tyres.

TYRE PRESSURES

There are no firm rules for 'Ideal' pressures. Driver, vehicle and circuit all have an influence Indicative COLD pressures as a starting point are:

Single Seater 16 - 18 psi Sports/GT 22 - 24 psi Touring Car 24 - 28 psi

If pressures are too low, structural damage to the tyre can occur. Look out for 'tuck under' shoulder wear, roll on cornering, slipping on the wheel rim or excessive pressure build up.

VEHICLE SET UP

Generally use more camber and/or castor with Radial construction Look for pressure build up of around 8 psi from COLD (slightly more may occur in extreme conditions) If 'bleeding' hot tyres to obtain the desired HOT pressure, check again when the tyres have cooled for a COLD pressure. This should be your starting pressure for that event. Optimum operating temperature range is generally 70 - 100 deg. C (non working wheels may not reach this range) Higher inside shoulder temperatures are acceptable.

Dunlop AMA SX