Tag Archives: changing tire size on same rim

Can you buy oversized tyres?


Hot On Wheels is a saying dedicated to the blitzing drivers who make rough use of their tyres of the automobiles. As it is commonly seen with almost all components, fatigue becomes an issue with tyres also, especially since they are being constantly exposed to continuous contact with the road, thereby developing frictional heating. This might result in faults or tears in the tyres, eventually making them unfit for on-road drives. Replacing the tyre is one important measure that needs to be done regularly with periodic maintenance and monitoring.

After deciding to fit in a new tyre in your vehicle, there is a particularly very important criterion that needs to be looked into, so as to get the maximum effectiveness from them. This aspect deals with the size and overall dimensions of the tyre to be incorporated. Retrofitting is an easy procedure but care must be taken regarding the diameter and thickness of the rubber materials.

There are mainly two different types of size defects related to tyres. They are oversizing and undersizing. Both result in the improper or inefficient functioning of not only the tyres, but also bring to question the whole dynamic balancing of the vehicle. This would make the tyre susceptible to mechanical wear and tear, irreparable losses and wobbling of the body while in motion.


Oversizing is the condition where the tyres diameter is higher than what used to be the original dimensions of the default tyre. This would affect the speed range of the vehicle, and the speedometer readings might mislead to wrong conclusions. This is because the speedometer is usually calibrated to the standard dimensions of tyre for every revolution.

Can you buy oversized tyres
Can you buy oversized tyres

If the size of tyre is increased, the time taken to complete a single revolution will be increased. Hence, the number of revolutions per minute (rpm) would correspondingly decrease. This would cause drastic effects in the gear shifting pattern of the vehicle. For cars with automatic transmission system, the gear shift would significantly get affected because it works on sensors that sense the cycles of rotation. Now if the cycle gets modified, the sensors might sense ambiguous speed ranges, thereby affecting the performance of the vehicle.


On the other hand, undersizing (the condition where the dimensions of the tyre retrofitted becomes smaller than the required size) might lead to enhanced difficulties with the rim. Small size of the tyre would mean that it would be fitted over the rim by exerting extra force. This always makes the tyre subject to extra pressures within them even when they are idle (cold pressures). Moreover, the load bearing capacity of the vehicle is usually vested to be borne only by the tyres. If their load gets reduced, it might put unnecessary weight on them thereby making them susceptible to more problems, and also taking a toll on the overall efficiency of the vehicle concerned.

So it is always a better practice to check for the exact dimensions of the tyre to be fitted in before getting it fixed into the vehicle. Tyres are one of the most important companions when you are cruising on road, make sure they are fit enough to carry the momentum forward, quite literally.