Modern Vespa

ScooterWest quotes a 2,000 to 3,000 mile belt life for the specially sized belt that comes with the GTS 300 Polini Evolution Variator (this is NOT the 9-roller variator kit, which can take a standard-sized belt, the evolution Variator only works with the special belt). Does anyone have any experience with the special belt? If so, how many miles have you put on it?

That seems like a really short belt life.

The big belt killer seems to be heat. If your belt case filter is dirty or otherwise clogged, it will kill a belt in a short period.

Maybe the belt side angle doesn't match the variator sheave angle well and it's stressing the belt in a smaller surface area than a stock belt.

Always check the CVT filter when changing oil.

Not many do. Most belts are 15 deg. Whilst many after-market sheaves are 14 deg. or even 13.5 deg. So it takes about 400 kms for one side of the belt to bed down to, say, 13.5 deg.

The belt is the picture above looks like a GT200 belt.

I've never had good luck with the polini transmission stuff. the rollers wear quickly and the belts besides their smaller displacement ones tend to have really short intervals as well.

for the 250/300's I'd only trust malossi.

Or just remove it altogether.

Those belts have a short life because of the extreme diameter the Variator moves out to. The performance on that Variator is insane, but at high top speeds the belt rubs on the casing on the bottom, by the sump. This leads to short life.

I have personally had them break on 3x different highly tuned bikes at around the 3000km mark, which is even less than what was quoted to you. Having said that, the bikes were routinely sitting at 140-150km/h for 20km intervals.

In my opinion, a good compromise is the new BGM Variator kit, which uses the same principle as the polini Evo but isn't as aggressive. It will perform stronger than the polini 9 roller, but not as strong as the Evo. I have fitted about 6x BGM kits now and they seem to perform well.

What kind of belly life are you seeing on the BGM? I really need about 6,000 miles.

I have seen belts last approx 7500km which, much like the performance, falls somewhere between the 9 roller and the Evo