Race Tyres

Tyres need to be speed rated to the speed attempted.

The fastest Vespa tyres are rated "P" which is 150 km/hr

Sava 3.50-10 51P MC 18
Schwalbe Raceman 3.50-10 10327541
Continental ContiTwist Race 3.50-10 M/C 59P TL

The tyres I use are Sava 3.50-10 51P MC 18 tyre Code 72761.

Speed Ratings

Most scooter tyres are rated "J" which is only 100 km/hr.

Speed symbol	G	J	K	L	M	N	P	Q	R	S	T	U	H	V	W	Y	ZR
Speed (km/h)	90	100	110	120	130	140	150	160	170	180	190	200	210	240	270	300	240+

Reading Notes

Reading Tyre Technology - Tom French

Internal heat generation is a problem and the times per second a tyre is deflected contributes to this heat generation. When the tyre gets hot enough the it "can lead to total disintegration". The book talks about a typical motorcycle tyre at 100 mph having 17-18 deflections per second.

My calculations are that at 100 mph a scooter tyre has about 34 deflections per second (twice that of a motorbike!). This is based on a tyre having a circumference of about 1.3 metres.

Comments

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