2023 Honda CRF250R with QS138 70H V3 Motor and EM260S Controller

[Dave Daum]

Many thanks, Don. I'm totally new this but have been pouring over these threads (and videos) and thanks to you and the others here, I'm feeling confident enough to take this on. Given my lack of experience, I'm inclined to go with the electric and co motor kit to take advantage of the controller tune and wire harness. Likewise, building a battery is way beyond my scope of knowledge/ability, so will likely go with Amorge as you've described. A woods rider is my ultimate goal, so will prioritize distance over sustained (or top) speed.
I'll add the KTM SXF to my list, although a cursory search suggests it may be harder to find one in my price range around my area. Part of the reason I asked about Kawasaki and Suzuki is that I've been finding more availability in later model frames at good prices...possibly says something about Suzuki and Kawasaki owners being more likely to seize their bikes .
Thanks again!

After following the advice from several members of the group, I'm making great progress with my 2011 Honda CRF 250R conversion. I'm waiting for my E&C kit. During the wait, I 3D printed a mock-up motor. This allowed me to fit check the Lithium King motor mount and to design an irregular shaped battery box. The battery box will accommodate 20s12p Molicel 42A cells. Thanks Don Cox, Bob Casper, Bayo, and the others for the guidance. I'll post some photos showing my progress.

 

[Dave Daum]

 

[DonCox]

Many thanks, Don. I'm totally new this but have been pouring over these threads (and videos) and thanks to you and the others here, I'm feeling confident enough to take this on. Given my lack of experience, I'm inclined to go with the electric and co motor kit to take advantage of the controller tune and wire harness. Likewise, building a battery is way beyond my scope of knowledge/ability, so will likely go with Amorge as you've described. A woods rider is my ultimate goal, so will prioritize distance over sustained (or top) speed.
I'll add the KTM SXF to my list, although a cursory search suggests it may be harder to find one in my price range around my area. Part of the reason I asked about Kawasaki and Suzuki is that I've been finding more availability in later model frames at good prices...possibly says something about Suzuki and Kawasaki owners being more likely to seize their bikes .
Thanks again!

You should be able to find newer YZ donor bikes, I have heard that the motors like to scatter themselves a little too often, and it isn't cheap to rebuild a motor that scatters. But Suzuki and Kawasaki provide a great base to build on, I just don't have any experience with them. Amorge can build to whatever shape you want, within certain limits. The battery we use for the YZ250F and also fit tightly in the CRF450, and it was exactly 6.25" x 8.25" x 12.5", with the connectors coming out of the front top of the battery. It is 20S12P with whatever cells you want in it. $1801 shipped to my door ( shipping might be different to where you live) with the P42A Molicels, an ANT Smart BMS, and a charger.
Get whatever donor bike you want, make a mockup battery out of wood, and see what fits. You can see this battery could be longer below where it is and in front of the motor, in the third picture, but just a different shape, or you can do narrower and longer like the forth picture. The forth picture is a YZ250F 2014

 

[Dave Daum]

Hello guys,

I found a few extra millimeters for more storage. I've changed the size of the battery to give me 20s13p for 72v 58.5Ah. I'm totally stoked! Here is the final battery box size:

 

[DonCox]

Dave, I told you that Amorge can make almost any size, but there are some limitations. The width of 6.10" is maybe doable, send it off to Amorge, and they will let you know if the can and will give you a price. Usually they stack 2 rows of cells in that direction, so that is why I think why they got our batteries down to 6.25". Let them tell you.
On the BMS , if you go with open discharge, you want the BMS to handle 40-50A charge. The one they put in the KTM battery was a 220/550A 480A Peak. That has I think 50A charge
Also if you go to Molicel P45B cells, you get a slight improvement in range. These are the cells they are using in the Starks. There are also P50B cells, the give you almost 20% improvement in range, but at the best price I could find, they were almost twice the price per cell ($8.50 per cell in quantity that we need) The P42A cost $4.35 per cell in our quantity, and the P45B are $5.27 per cell.
Are you still planning on coming out this Saturday? Bob Casper is thinking to come out also.

 

[fsfs]

Dave, I told you that Amorge can make almost any size, but there are some limitations. The width of 6.10" is maybe doable, send it off to Amorge, and they will let you know if the can and will give you a price. Usually they stack 2 rows of cells in that direction, so that is why I think why they got our batteries down to 6.25". Let them tell you.
On the BMS , if you go with open discharge, you want the BMS to handle 40-50A charge. The one they put in the KTM battery was a 220/550A 480A Peak. That has I think 50A charge
Also if you go to Molicel P45B cells, you get a slight improvement in range. These are the cells they are using in the Starks. There are also P50B cells, the give you almost 20% improvement in range, but at the best price I could find, they were almost twice the price per cell ($8.50 per cell in quantity that we need) The P42A cost $4.35 per cell in our quantity, and the P45B are $5.27 per cell.
Are you still planning on coming out this Saturday? Bob Casper is thinking to come out also.

View attachment 12329

There was a guy with a very long Molicel P45B, P50B comparison on youtube. In short, the 50 is only a very slight improvement over the 45. In the real world the gains are not nearly what the data sheet reflects.

The difference in the 42A and 45B was night and day. Going to the 45B made the Varg a better bike. The biggest gain comes from the lower resistance -- voltage sag and battery heat was significantly lower with the 45Bs. The real world gain from the 42A to the 45B was more than the data sheet reflects.

If it were my bike I would go with the 45Bs, with the 50Bs not nearly worth the extra expense. Just IMO.

 

[fmxxx666]

@fsfs I know exactly the video you are talking about after watching that I also decided to go with the P45B Cells.

here is what I just Orderd at Amorge:
22S13P Open Discharge (BMS only for charging up to 50A) Metal Case

 

[Dave Daum]

I just now emailed Allen at Amorge and asked to change from 45A to 45B cells. Thanks guys.

 

[DonCox]

@fsfs I know exactly the video you are talking about after watching that I also decided to go with the P45B Cells.

here is what I just Orderd at Amorge:
22S13P Open Discharge (BMS only for charging up to 50A) Metal Case

View attachment 12330

What are the dimensions of your battery, and what bike are you putting this in?

 

[fmxxx666]

@DonCox it’s for my 2009 CRF 250

but frame should be the same from 2006-2009 CRF 250

I used also the available space inside the Gas Tank