48 volt motor with 12 volt motor question

I'm building a motorized bike. specifically i'm putting a 80cc motor on a beach cruiser but i was going to also attach one of these as well http://www.electricbikefactory.com/index.php
I planned on having a big basket in the back and putting a deep cycle marine battery in it to replace the little battery it comes with and having one of these charge it. http://www.harborfreight.com/45-wat...e=pe&ctype=2&gclid=CKrA8tiatqgCFQl_5Qod4S-RCA
i just got a ezip trailz bike from a friend but he didn't have the charger or battery. I see it has a welded on slot on the frame where the motor attaches and was thinking of adding this motor and its freewheel as well to my motorized bike that i'm building. I would have to get that attachment cut off and welded on to my bicycles frame but i'm already planning to have welding done on my bicycle so i can use my bicycles frame as and exhaust pipe and possibly welding on a back rack. viewing the side of the ezip bikes motor i remember it saying 48volts. the information on the electric motor that mounts on the front wheel says its a 12 volt motor and the battery that comes with it says its a 12 volt 18 amp battery. can i hook them up directly to the marine battery or do i need some type of voltage regulator or resistor or fuse or something? Is it worth the hassle you think to hook them both up? I only thought to do so because one battery for the ezip is 120 bucks and the charger is another 25 at least. both of the motors seem to say they do about 17 to 20 miles an hour. just listening to this after i've written it i've decided not to do it but i spent so much time writing this i might as well post it. happy easter:idea::worthless:

 

Sorry, but I didn't quite follow your plans. But I picked up on one or two things that I can comment on.

I don't see any way of using the ezips left side freewheel with an 80cc gas engine. that freewheel will be right where you need to install the engine's drive sprocket.

The ezip probably has a 24 volt motor. At least, that's what most of them have. On this bike the electrical contacts between the stock battery case and the bike's electrical system are a bit weak. I had to replace mine pretty quickly, in any case. A 12 v/ 10 amp/hr sealed lead acid battery can be found for about $40.00. Two of them plus an automotive battery charger could be had for just a bit over $100.00. That would at least get you up an running. In my case, I run four batteries in a series/parallel arrangement. One battery mounted near the axle, front and back-one on each side. If you actually have a 48 volt motor (I'd double check this), then you could run four in series.

Then you'd still have the gasoline engine to use on a different bike.

I hope this gives some clarity. I'm not sure, actually.

But good luck in any case.