You need to check to see if your international license permits you to drive a motorcycle. Bolivia, like most other countries expect, expects you to have a special license to ride a motorcycle.
Here in Bolivia there are check points checking to see if you have the correct paperwork. Being a foreigner they will probably give you more trouble than if you were a native.
To get a Bolivia driversBolivian drivers' license you need to be a resident.
You need a local medical checkup and you have to go to drivers school. You will also need several certificates from several different police stations.
Here is a link for reference: http://www.segip.gob.bo/web/index.php/requisitos-para-obtener-la-licencia-para-conducir