the hobbit tail light assembly must be wired differently, otherwise it wouldnt die. being a 91, it wont have the resistor in the tail light, but rather, a voltage regulator mounted on the right side frame under the engine cover. make sure both yellow wires are plugged into the regulator, and that it is grounded good. dying as the brakes are applied tells me you dont have the tail light assembly grounded properly.
there is no low end mixture. it is fatory pre-set. i would;
clean the exhaust
make sure the engine has 120 lbs or higher compression
make sure the air box and filter are clean
install a new champion l86c spark plug
there are some k&n performance filters. but the wire mesh one is stock for most peds.
yep, all tomos are made in yugoslavia. they are the best peds out there in my opinion.