Have been doing it for years as I refuse to give up my home license which entitles me to drive in a great number of countries without an international permit for a Taiwanese license which doesn’t. You bring your ARC and international permit to the DMV, fill out a form and the they stamp and staple an addendum to your permit, it’s for a maximum of 1 year, will be less if either your ARC or permit has less than a years validity remaining. I have “heavy” motorcycles and cars on mine.
You can check the rules on the DMV’s own website, DMV, quoting from there, “Only people with an IDL issued by reciprocating countries and staying in the country fewer than 30 days can drive without additional permission. If foreigners wish to stay more than 30 days they should fill out the IDL permit application form and submit it to the highway inspection department. The longest validity for an IDL permit is one year. If the permit validity date is shorter than one year, the validity shown on the license or document applies. After expiration, permission to drive ends.” The bolding is mine. You may be running into an issue with reciprocity, assuming you are from Belgiun then there may be a limitation as Belgium only allows Taiwanese to use an IDP for 3 months in Belgium, check here DMV
They typically aren’t clear for “heavy” motorcycles, if your IDP and home license states a “heavy” motorcycle category then you should have that on the stamped insert they gave you. If I remember correctly mine states something odd like motorcycles to a maximum weight of 600kg which isn’t really a limitation as I can’t think of any offhand that weigh more than that or even close…
Never had an issue, I’ve actually never had to produce my license for an insurance company. Had a recent accident (not my fault) and there was no issue with license or insurance.