What you need to know about Spacesaver spare tyres

If you’re properly prepared for a flat, knowing where all the equipment is to change the wheel and how to fit the tiny replacement the car manufacturer has supplied in lieu of a full-size spare, the real questions begin.

So how fast can you drive while you complete your journey and make plans to repair or replace your original?

The key is to know that stability, not speed, is the enemy of the space saver spare.

The temporary replacements are usually only rated to 80km/h but the speed limit is more about staying safe than any shortcoming in the design of the skinny spares.

“Switching to a space saver tyre means one tyre is different to the other three on a car, which naturally will change the handling of a vehicle and change corning and stopping characteristics,” says Jon Tamblyn, national technical field services manager at Bridgestone Australia.

“While skinny space saver spare tyres obviously have lower performance than a conventional tyre, the main limiting factor is mismatching wheels and tyres on a car, which affects the handling.”

But there are tyres which can be run safely at more than 80km/h.

“Space saver tyres are designed to be quite capable tyres and are often rated to 130km/h, with a load rating suitable to the vehicle. They operate on a similar principle to a bicycle tyre: a smaller tyre running at a higher pressure to carry the load and speed.”

Regardless of the speed, Tamblyn emphasises the need for an early change back to a full-sized regular tyre after a flat.

“This limit is to ensure driver safety and is also why motorists should only use space saver tyres as a short-term measure to get their damaged tyre replaced,” Tamblyn said.

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