If you're caught in California driving a motorcycle without a motorcycle license then the fee for the first offense is $250.00 and you'll usually have your motorcycle towed and impounded and so you'll have to pay those towing and impounding fees to get your motorcycle back.
Then if you're caught a second time without a motorcycle license you'll also have your motorcycle towed and impounded and could spend 6 months to a year in jail.
And you will usually also get another fine or ticket of $1,000.00 so it's not worth it to ride your motorcycle without having a motorcycle license.
The cost of the motorcycle license is cheaper compared to paying the fines and spending time in jail which is not fun.
Plus the costs of towing and impound fees.