IV - THE MAIN PROBLEMS

The 7 main defects

Cracks

Splits / Crown

crown sidewall

DESCRIPTION

Damage to sidewalls with or without puncture instead

of perforation and/or tears.

CAUSES

External aggression either by running over sharp/blunt

objects or by rubbing against a foreign body.

DEVELOPMENT

Rubber and/or plies broken on the sidewall, running

underinf lated.

CHECKS / ADVICE

•Check the conditions of use.

•Check pressure used.

•Replace the product(s) concerned if the damage

is extensive and has reached plies or the carcass.

DESCRIPTION

Crown damage with or without puncture and/or tears

and splits. Localised breaking.

CAUSES

External aggression either by running over sharp/blunt

objects or by rubbing against a foreign body.

DEVELOPMENT

Damage to a tyre by running underinf lated, breakage

of plies, product delamination.

CHECKS / ADVICE

•Check conditions of use.

•Check pressure used.

•Replace the product(s) concerned if the damage.

is extensive and has reached plies or the carcass.

crown sidewall

DESCRIPTION

Localized or widespread cracks in the rubber - radial,

oblique or on the circumference - of varying sizes that

may reach the plies. These breaks may be on all sidewall

areas of the tyre.

CAUSES

Visible damage in the f lexed area.

CHECKS ADVICE

Types of surface of use

Roads paths accesses

Speed load pressure

Inspect the other tyres on the vehicle

Adapt pressure to use

Replace the products concerned if the splits are deep

or have reached the plies or carcass

DESCRIPTION

Splits in the rubber on the crown, edge or base of tread,

with or without radial or circumference tears

CAUSES

Conditions of use

DEVELOPMENT

Risk of contamination with damage to crown or sidewall

CHECKS ADVICE

Check conditions of use

Replace the products concerned if the damage

is extensive and has reached plies or the carcass

MICHELIN MOTORCYCLE AND SCOOTER 181

Technical data