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Hey all!
I am in the process of my first EV conversion and I thought I'd find a place to get feedback, suggestions, and just generally try to benefit from the wisdom of those who've been through the process. I will be converting a motorcycle for the purposes of a commuter vehicle. Goals are a top speed in the neighborhood of 45 to 50 mph and a range of ~20 to 25 miles on a charge. With the components I already have I think these goals are achievable but as with anything new I am certain there are complications I have not considered. That is where you guys will hopefully come in.

I have a friend in the EV industry who has been assisting me in selecting and acquiring the drive components (motor, controller, bms, can charger etc) and will be tuning the system for me once it is built, but his expertise does not translate to the conversion of an existing vehicle and since I'm sure he is already sick of my endless questions I am hoping to get y'all involved. Let's start with what I've already got. 20200301_155021_1583175433176.jpg
Motor is Motenergy ME0201012801 http://www.motenergy.com/me0201012801.html
Motor controller is a Sevcon Gen4 and is configured for 48v with 100A continuous. Don't remember peak at the moment.. http://www.sevcon.com/products/low-voltage-controllers/gen4/
BMS is a CAN enabled Orion Jr 2 (battery pack is 16s 4p so each parallel chain will be treated as a single cell but the cells are brand new and have been balance tested so I feel comfortable with this configuration) https://www.orionbms.com/products/orion-bms-jr/
Charging unit is an ElCon HK-H-H66-25 https://www.elconchargers.com/catalog/item/9034090/10295151.htm
The throttle is an inexpensive hall effect unit that I bought Ebay.
The battery pack is 16s4p and is built from 38120 HP cells that i was able to source brand new. http://www.headway-cn.com/en/showproducts.php?id=1560
I also have all appropriate fuses, mains contactor, CAN connectors etc.

What I am left with is deciding on what donor bike will best suit my needs, and the mechanical aspects of the build such as motor mount, sprockets, battery box, mounting bms and controller components, chain guard etc..
I'm currently looking for a donor bike somewhere in the kz440 to cb750 range. Don't want a bigger bike than necessary so I can keep the weight down, but need enough space for everything and it has to support a big guy (I'm 6'5 and 260 lbs).
Any and all comments, suggestions and assistance is welcome! If it gets some interest I will update as the build progresses. Thank you all in advance!
 

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Some things I forgot to mention.. the controller, bms, and charger are all CAN enabled and will be configured for maximum system safety and stability. I only mention this because when my EV friend suggested the Orion Jr 2 I expressed some concern about treating each parallel string as a single cell. His opinion was that because the sevcon, the Jr 2, and the ElCon are all robust, well made components with seamless CAN integration the risk of damage to or failure of the battery pack due to cell balancing/thermal issues is highly unlikely.
 

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Paralleling cells in the way you've described carries a very low risk, especially with new, well-balanced cells. I'm in the process of building a pack of 92s4p 20Ah cells and it's really fine to do it this way. The Tesla Model S battery packs are built this way, except instead of 4 cells in parallel, their modules are 6s74p. They fuse each cell with a fusible wire link, which if you're worried about safety, you can do.
 

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Paralleling cells in the way you've described carries a very low risk, especially with new, well-balanced cells. I'm in the process of building a pack of 92s4p 20Ah cells and it's really fine to do it this way. The Tesla Model S battery packs are built this way, except instead of 4 cells in parallel, their modules are 6s74p. They fuse each cell with a fusible wire link, which if you're worried about safety, you can do.
Thanks for the feedback! Good to hear that the method is being used safely by others. I'm just waiting on my 110 copper and then I can make my bus bars and bench test the system. Can't wait to get it all hooked up!
 

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I would have to suggest a cb750 frame would work best as it has the frame and size you're needing. That was the more larger bikes back in the day and any bigger cc bike (cb900 and so on) are the same frame just different motors. You could make a cafe racer style cb750 to modernize the fashion of the electric vehicle. The kz440 frame is for a twin cylinder bike and would be too small in both the components you have along with the size of individual you are. You can fine these bikes pretty much anywhere.

Eager to see the progress.

Could you have a list of costs you've endured so far with those components? No one has really done a cost analysis of a bike conversion so I would be really curious.
 
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