You need to run a clutch pulley with the clutchless varriator. You can't pedal with a clutch pulley without the motor turning over, it's kinda a pain. The model with clutch function replaces the varriator part of the stock setup using the stock clutch, it's prety sweet.
A really cheap and pretty easy option is to just take apart your stock varriator and replace the weight plate things with weights like this they fit on the stock varriator. Only problem is you have to take the whole thing apart every time you change the weights, but it only takes a few min once you get the hang of it.