[roadster]

Beware of assuming that removing the air box or de-restricting the exhaust automatically means that the engine will run weak because more air will flow through it. It isn't a continuous flow system its a pulsing or vibrating one and both intake and exhaust resonate by design. By all means experiment but you may find results can be counter intuitive.

 

[roadster]

One way to evaluate changes is to use a GPS device such as Garmin to record your track over a pre-determined test route. Make sure the route has a longish uphill section and try to choose quiet roads where traffic is unlikely to impede progress. Also try to test on wind free days because with bikes as small as this headwinds make a huge difference. GPS data from recorded tracks can be exported and analysed in detail using GPSBabel and a spreadsheet if you want to get really scientific.