Parts for these machines are slowly becoming available from European manufacturers.
The biggest single improvement you can make is by fitting one of the exhaust systems. To see the difference look at the Dynojet graph below comparing the standard exhaust with an aftermarket Giannelli Freeway exhaust.

The larger 21mm carb kit from Malossi improves this again, but the major change is the exhaust.
There are also some improved transmission parts available that extend the range. We will provide Dynojet graphs showing the use of these parts as soon as we have them available.

With the exhaust fitted the power output is so much improved that the 100 is even more under-geared than standard and can usefully do with gearing 20-25% higher. As soon as we have chance to check out the internals we will sort one out but I’m sure the Italian aftermarket parts manufacturers will have something available soon.