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[Gregski]

OK, so I started learning about batteries, and some basics, standard car batteries are about Cranking Amps (bad) we need ones that are about Amp Hours so we need Deep Cycle Batteries, (good).  Lead Acid Batteries is what I can afford, so let's talk about those.  I plan on using six 12 volt 100 amp hour AH batteries and a 72 volt 100 amp motor.

First of all who came up with this crazy amp hour rate system based on 20 hours, I mean what's the significance of 20 hours.  It's not even a day's worth.  Then some provide amp hours in 25 hour increments, other's in 5 hour.  Now somewhere I read you take the 100 AH divide it by 20 hours and you get 5 amps per hour.  Though some battery specs show a different 1 hour rate then if you divide it by the 20 hour rate, what gives?

Now since I will be connecting these batteries in series (plus to negative, plus to negative, plus to negative, etc) the volts will add up 12 + 12 + 12... = 72 volts.  However from what I gathered, in a series the amps stay the same so they will not add up, so I will still have a 100 amp system at the 20 hour rating.

So does this mean if I plan to ride the bike for 1 hour the motor will be sucking in 100 amps and therefor running at it's theoretical peak performance, aka providing 100% of its horse power?  Assuming somehow I gauge it / throttle it in such a way.

To follow up on this question, if I ride bike for 2 hours will it be using 50 amps per hour, and running at 50% horse power? Assuming somehow I gauge it / throttle it in such a way.

[Bogan]

with lead acid batteries, the faster you draw the current from them, the more energy is wasted, so if you get high amp hour batteries and draw that current really fast, you will get less amp hours than the batteries are rated for. When choosing lead acid batteries you MUST check that the battery can generate the high currents needed for extended periods of time, otherwise the battery will most likely collapse internally. So the amp hour rating you look at would be the 1 hour, or 5 hour or whatever the smallest given is.

yip you are right about the amps staying same as you add (series the batteries) the voltage. If you parralel  the batteries then the voltage stays the same and the current would add.

Not exactly sure what you are asking with the other questions, but essentially current through the battery is directly related to the power, full current = full power, and yeh the controllers generally have overcurrent sensors so you can adjust the max current you put through it

[NewAge]

Gregski... You are doing a bunch of math but are you aware of the amount of weight you're talking about. 100 ah lead acid batteries weigh about 60 lbs each and you want to run six of them, that's about 360 lbs  ... remember balance  somethings gotta give, seriously, a bare chassis with motor and controller less batteries would be probably 150-200 lbs all by itself, then add 360 in batteries and a 180 lb rider and you have 700 to 800 lbs that you're powering down the road.

Also, I hate to say it but your math did not take into account the fact that you should never run your battery pack below 35% capacity or they will not provide nearly as many recharge cycles so whatever number you came up with for power/range subtract 35%, sorry.

Check out this guys set-up http://www.electricmotion.org/ This represents a very nice thought out package.

[Bogan]

yeh i agree with newage, thats a lot of batteries, and a lot of weight, i should have mentioned you really need deep cycle batteries as these can discharge a lot more than standard ones and not lose any significant capacity.
I think you should have a look for some ex hybrid batteries, think they are 1.2V D-cell 6Ahr capable of 100A each!! well the ones my mate has are anyway, and they would allow you to fit more in, and use the original fairings to make it look nice too