I installed a conical air filter as well. It is quieter with the factory box intalled. As far as performance goes the two are similar. Youtube has a video about this (done in Australia). The guys were doing sort of a loose spin off of Mythbusters. Instead of testing a scooter it was a Honda S2000 car. They put the car on a dyno with the factory box installed and ran a test, then tested the same car with the conical filter installed. The results: There wasn't a lot of difference in horsepower or torque to get excited about, it was a 3% gain with the aftermarket system.
If you translate the results of the Honda S2000 to a 35 horsepower single cylinder Burgman engine, I'd say the only gain you would make is a quieter engine.
Air box design is not just a fluke. A lot of engineering goes into it. It has a lot to do with the volumetric efficiency of each engine. Some times it can be improved but MOST times all it does is improve or runes the SOUND of an engine.
If I were to add a Leo Vance exhuast, different slider/rollers in the CVT, different clutch and any other mods then I may change out the air box. But I would just modify the stock air box with maybe an external filter mated to it. But with all these mods the power level will not be much higher that stock, just at a different place in the RPM or at road speed areas.
On two wheels now, one is a car tire. Looking for a 2F1R trike.
I am poor, please do not ask me for money or tools. I will ride 100 miles to help for a beer and sandwich.
All I know is I have all the mods installed and had a tech at Fuel Moto that does dyno tuning take it for a ride. He said it was tuned perfectly with plenty of power and smooth power delivery throughout the range. He could not fit it on their dyno but has been tuning for a long time and could get a good feel on the test ride. He was gone for quite a while and said he tested it at all speeds and acceleration tests.
It has been super reliable and all the performance I ever wanted in my trike so a pretty happy with the performance of mine