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try_all replied to the thread Aprilia electric supermoto.
Quote Originally Posted by Electro Flyers View Post
Nice looking work! What was the original motor again? GM? Do you have a picture of it? Also, is the pack voltage 400 Volts like on the warning label?!!
yes i started out with goldenmotor, pack voltage is 74v nominal, that label is only for joke lol "

18 Hours Ago

Electro Flyers replied to the thread Aprilia electric supermoto.
" Nice looking work! What was the original motor again? GM? Do you have a picture of it? Also, is the pack voltage 400 Volts like on the warning label?!! "

19 Hours Ago

T Rush replied to the thread Aprilia electric supermoto.
" yeah man!

I've seen your first video a few times...nicely done...I think it had a big influence on me to want to do my project

so are you going to make another video now that you upgraded the bike? "

1 Day Ago

T Rush replied to the thread Need help to figure out the battery.
" you might consider a higher voltage system for such a large battery pack using so many cells

other forum members hopefully know way more about this than me...as I am new here

I don't fully understand the voltage vs amp hours thing yet, which is better to have more of....but I think most of the big company EV manufactures use higher voltage systems with many more modules(groups) in series, with fewer cells in parallel in each module..and I don't know exactly why, but it might be some simple obvious answer for someone who has more experience with electric than me "

1 Day Ago

try_all replied to the thread Aprilia electric supermoto.
" The bike has been re built with me 1507 ipm motor and sevcon size 6 its ready to race now

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Attachment 7582 "

1 Day Ago

T Rush replied to the thread Need help to figure out the battery.
" 800 is still a lot, and will cost much... you also will have to figure out how big a 800 cell battery pack will be, and if you can fit it in your motorcycle frame

you could even start with 500 or 600....and then later add more, but to add more you will have to take the whole battery pack apart to add cells into the parallel cell groups to increase amp hours for run time
...if you just added a new 'group'(or they call it a 'module') in series, then you increase voltage "

1 Day Ago

EVcycle replied to the thread Caffeine and Octane Motorcycle Best of Show - Our electric !.
" Thanks
Originally built 8 years ago with Headway batteries. It has a Mars 1003 Brush-type PM DC Motor, sealed contactor and a Magura 0-5K Twist Grip.
It currently has 2 Chevy Volt 12 cell battery packs set up for both bulk and individual cell charging (small wall plugin chargers). The street gearing is
14-54 with a aluminum rear gear and Renthal R1 420 Chain. I have yet to wear out the chain. I have had a spare set in a box forever.

No BMS. I do not ride it to within an inch of the battery life and cell charging keeps things balanced. The controller will shut it down if the battery pack gets too low.
No lost cells to date. It has a cycle analyst so I have all the data I need. It currently weighs 380 lbs total. It has the "street" 600 Amp Kelly controller in it now.
The race one is 1200 amps.

It is nimble, fast and a blast to ride. It is a nice simple clean setup that has proven to work well throughout the years. "

1 Day Ago

electric.supermoto replied to the thread Need help to figure out the battery.
" ...

Thanks for you answer ...that what i calculated so i was pretty right but it seems that is is a lot of 18650 to go in the frame of the motorbike (that's why i thought it was wrong but in fact it is not)do you think if i get 800 of them it would be enough to ride in the city?? "

1 Day Ago

T Rush replied to the thread Need help to figure out the battery.
" let me see if I can get this right(as I'm still learning)...as I was curious to what I'd figured out before, and if my math was correct

it is important to decide the capacity of the battery you will need...too small and you don't get the range, too big and it weighs extra and slows you down

I was looking at what the big name brand manufactures get for range at highway speeds, and what level of battery they use to do it
...like the Zero Motorcycles http://www.motorcycle.com/mini-featu...cle-range.html
looking at that info, lets say you need a 10kWh battery to go 62miles at 62mph with a lighter aerodynamic motorcycle
(so that would be my 100km @ 100kph, with the 100volt X 100ah = 10kWh battery for a 100kg bike)
...and with your 72volt system you are designing...then you need a 139ah battery
(72volts X 139ah = 10kWh)

using the 3.7V 18650 cells, you need to have about 20 'groups' of them in series to get 72volts
(3.7volts X 20 = 74volts)
...but each one of those 'groups' needs to be made up of a block of cells in parallel to get the amp hours

you might get 18650 cells rated at only 2600mAh
(so many fake ones out there with different ratings...I wouldn't know which ones to get to actually achieve the best 3ah or even the 2.6ah I'll use here)
....so each one of those 'groups' would have 54 cells in parallel to get up to 139ah
(2600mAh X 54 = 140ah)...so this is where the total number of cells needed for a 72volt battery pack multiplies way up

so by my calculations; to build close to a 10kWh battery you would need about a thousand 18650 cells
(54 cells in parallel for each group X 20 cell groups in series = 1,080 cells for 74volts 140ah)
...a thousand 18650 cells also can work out the same for different voltages and amp hours designs
it could be ... 27 X 3.7v cells series = 100volts, 39 X 2.6ah cells parallel = 101ah ... for 1,053 cells total
(27 cells series X 39 cells parallel = 1,053 cells and 100volts X 101ah = 10kWh battery pack)

18650 cells weigh about 45g each, so a thousand together would weigh 45kg(about 100lbs) so that is a pretty huge battery
...now keep in mind that battery would give you maybe twice that range at slower speeds in town, so riding at 50kph and you might be able to go 200km or even further
...so you might not really need that big of battery....and I was just guessing that a 10kWh battery is necessary for 100km @ 100kph
(you might find that you need a larger battery pack, or maybe a smaller one depending on motorcycle and rider: weight, size, aero, and power efficacy)

you will still be able to hit a max speed of 100kph with a smaller battery pack using fewer 18650 cells...say you only buy 400 cells
still you would have 20 groups of 3.7v cells in series for 74volts.. then just 20 in parallel for each group at 52ah(the 'amps' will just get used up faster when riding at 100kph, and wont last an hour; maybe 20min run time at that fastest speed)... however, that smaller 3.8kWh battery might still last 100km if you only ride at 50kph(so then the bike would run for two hours at only a slow 50kph)....and with the lower weight; it will be quicker(more fun) to get up to 100kph, and stop faster "

1 Day Ago

T Rush replied to the thread Need help to figure out the battery.
" I can not tell you my exact calculations...but I played with some of them to try and figure out how many 18650 cells I would need
the basic formulas are simple:

voltage per cell X number of Cells in Series = Volts

ah rating per cell X number of Cells in Parallel = Amp hours


Volts X Amp hours = Watt hours

...as I understand it: "Volts" is how quickly the electricity can work(with a battery, the voltage will vary with the state of charge; a normal 3.7v cell might be fully charged as high as 4.2v, and drained at 3v) fast(high voltage) or slow(low voltage) frequency, no matter how much its actually doing at once...kinda like spinning away crazy if without any amps
"Amp hours" is the amp level a battery can output if it was drained during one full hour of time; with battery storage, 'time' is the key factor, and 'amp hours' are different than a single momentary 'amp' load, and you could use it faster than a hour and get more amps all at once(so like it could be 3amp load for an hour, or 6amp load for a ½hour, or 12amps load 15min. etc) so how much the electricity can actually do no matter how fast or slow it does it, all at once or spread out over a longer time...kinda like sitting there doing nothing if without volts
"Watt Hours" is the total capacity of the battery pack...it can be high amp hours with low volts, or low amp hours with high volts and still be the same(so like digging slow with a shovel, or digging fast with a spoon...but still digging the same size hole in the same time)
...there is also "current" which might be how fast and how much a battery pack can flow its power; like high current to a motor could suck a battery dry quickly and give you lots of motion power to move mass far and fast, but low current flow and you are barely moving anything or anywhere slowly with long battery life; the job of the 'controller' between the battery and motor
"Series" battery cell connection is when they are lined up end to end with the + on one going to the - of the next
"Parallel" connection is when the battery cells are all next to each other, with all the + ends together but separated from the - ends wired together
number of Cells in Series X number of Cells in Parallel = total number of Cells in the battery pack

...but when I was looking to do 100kph for 100km, the 18650 cells seemed to be the only battery pack that would do that with keeping the weight and size of the bike down
(I was trying for around a low 100kg motorcycle weight, with 100v X 100ah = 10kWh battery pack)

you should be able to build an el.motorcycle that would reach a max speed of 100kph
an el.motorcycle that can go 100km distance

...either of those might be pretty easy...but building one that can do both at the same time(run for one hour @ 100kph for 100km) and you will need to have everything in 'perfect balance'! [weight, size, aero, power, battery]
so there might be other sacrifices(like you might need something more aerodynamic than a supermotard, you might not have lower speed performance, and you might have to use a smaller motor with lower weight)

good luck
...and I will be watching to see if other forum members know how to do it! and help you "

1 Day Ago

T Rush replied to the thread Caffeine and Octane Motorcycle Best of Show - Our electric !.
" awesome...congratulations!

that IS a smart looking ev motorcycle
being a kinda new fan of Hondas ....what else can you tell us about it? "

1 Day Ago

electric.supermoto created the thread Need help to figure out the battery.
" Im a student in nz and want to build an electric supermoto. I think I'm going to go for a 20kw motor 72volt 330amps.the problem is that i don't know how to calculated how much 18650cell would i need(first is it the good battery to use).I would like to have a max speed at 100Km/h and ride for about 100Km .
could anyone help me
Elian "

1 Day Ago

EVcycle replied to the thread Caffeine and Octane Motorcycle Best of Show - Our electric !.
" Thanks, the Comstars are original to that bike. It was a SS in its former life. That is what they made the "R" version out of.
The fiberglass is from the original molds from Honda. We ran the bike with the Historic Moto Gran Prix group as it was period
correct enough. You are allowed a motor change and they liked the idea of it having an electric motor.

Attachment 7580

and Yes..... I have linux.... "

1 Day Ago

Spaceweasel clicked Likes for this post: USA Leaf owner wants to convert Derbi supermotard by T Rush

1 Day Ago

Stevo replied to the thread Caffeine and Octane Motorcycle Best of Show - Our electric !.
" Congrats! Very cool old school cafe look. Are the comstars off an old Hawk? "

1 Day Ago

EVcycle created the thread Caffeine and Octane Motorcycle Best of Show - Our electric !.
" For any of you that have not seen the Caffeine and Octane Show, It is a national car show that regularly attracts
over 2000 vehicles and 15,000 fans every month. (NBC Sports)
The event is held (rain or shine) the first Sunday morning of each month from 8AM - 11AM at Perimeter Mall,
located on the Northside of Atlanta in Dunwoody GA.

This past weekend was the second annual Caffeine and Octane at the Beach and was held at Jekyll island, Ga.

It was the first year for a Motorcycle to get an award and of all the great motorcycles there...we were given the nod.
The announcement given by Ricky Gadson (11 time motorcycle Drag racing champion) was cool as he described the
bike in Watts and not HP.

We had a great time and this show is not to be missed. We met great people, ate excellent food and the cars and
bikes are from some of the best builders in the world. The crowd was great with a lot of questions and good comments.
The award was a shock considering some of the rides there and was icing on the cake of a fun weekend.

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Attachment 7575

This photo is where they asked us to be in the background while they were doing some TV shots....Fun stuff !

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2 Days Ago

T Rush replied to the thread USA Leaf owner wants to convert Derbi supermotard.
" thanks for keeping on posting stuff guys, it really helps...while I might not totally jump on board right away with your recommendations...it does make me think, and this is the stage for lots of that, then rethinking lots more

so, I looked at it again (my Wife gave me a ride to the shop so I could get my circular saw and still drink green beer) so while my Wife was at the grocery store, which takes her a long time; I noticed a few things

1) space for the motor up high in the rear sub frame is pretty tight; might have to mod that part of the frame some, but I'd think it would have to be reinforced anyway as the motor has to pivot(like an alternator on a car) for belt or chain tightness ...so that might get extra fancy(more than I'd want it to)...I can tell already this will be an issue, with the motor trying to twist itself right out of there, and not being in the 'strong part' of the frame designed for the engine

2) jackshaft space is limited....I did think earlier about the swing arm axle pivot being the support for a jack shaft tube(as Richard230 just posted above) but my swing arm and frame narrow right there(where it would need to be wider for both chains/belts to clear beside the tire)...a jack shaft will keep the drive sprocket closer to the swing arm pivot like the ICE/trans had it...and there is way more space for a jack shaft than a 8"dia motor(there is no way any Leaf modules would fit inside the frame if the motor was there)...the jack shaft concept and changed motor location is so I can use Leaf battery modules....without the Leaf battery I looked at 18650 cells, but then there goes my range or run time, and I'm doing just one of those popular Chinese eBike kits ...heck, I'd just buy a Sur Ron

3) I do have other non running motorcycles....namely I have two CB/CL 350 Scramblers(one I paid $175 for, a week later someone saw it and gave me another matching one)....one of them I put new tires on, beefed up NOS vintage aftermarket rear shocks, heavy front springs, and started cleaning it up to do a cafe racer style(I called it a "Cafe Sport")...the other I used the parts I took off the cafe to build it back to stock, but its engine is screwed....sadly nether has any paperwork, so never bothered to run them http://trushcafesport.blogspot.com/
...but they have way more space for a bigger motor(normal location) and battery

4) I just really want to sell that gixxer...yes, I was/am in love with that bike...but I'm never going to ride it again(would rather be on my CBR1100XX Super Blackbird) and selling it would pretty much fund an el.motorcycle build "

3 Days Ago