>>i was just wondering if any upgraded parts like mufflers or 70cc kits work on Batavus mopeds.<<
One of the forum guys has a page on Batavus modification...search the forums a bit and you should find it...might be in resources links too.
>>And are other brands of moped engines able to work with different mopeds. ex. could i use a tomos engine in a batavus moped?<<
I've done it, don't know that anyone else has....but it IS possible in some cases, just a lot of hard work.