s1dewinder
1 mW
- Joined
- Aug 11, 2020
- Messages
- 15
I plan on building another ebike. I have some design goals, a rough components list, and a dream.
In short: I want a fat mountain bike e-moto conversion with dual electric drive and no shifting (single speed).
Design goals:
It must be possible to assemble the bike from existing components in the market. Required handywork must not exceed wrenching, filing, and soldering. I don't have access to custom parts or a machine shop.
170mm rear drop out fat bike conversion build (from components, not from an existing bike)
Dual electric rear wheel drive: mid drive+direct drive rear hub (don't try to stop me, this element is non-negotiable)
Must be able to handle the heat generation of full throttle on a 10% grade from a full charge to nearly dead and then roll back down the hill with regen braking. Again, without risk of overheating. Assuming a 220 pound rider.
60 MPH top speed.
Single speed
No tubeless wheels
Frame: 18” Framed Minnesota 2.0/3.0
I built my current ebike on the 20 inch version of this frame. I love it. Huge triangle space. Rides great with the seat slammed. Very much like a mountain bike but fat. Sportier geometry, like a more acute rear angle, would be cool, but I do love this frame. Going smaller, 20" to 18", should yield a small gain in agility.
Rear direct drive hub and wheel: ENC3000
I've used this motor in the past on my current bike and I love it. It's 11.94 Kv, so it is a relatively fast winding. The primary reason for using this motor specifically is because Ncyclebike told me they could send me one with a 170mm compatible axle laced into a 19" motorcycle wheel. (I'm considering going 17" for less weight, more stiffness, more agility, and more torque). They also told me they could send me an 11 tooth single speed rear freewheel for it.
Mid Drive: CYC X1 Pro Gen 2
With a BAC 855, 12/72 gearing, and an 11 tooth rear freewheel. Disable/bypass PAS and spoke speed sensor.
Rear hub controller: Phaserunner
This controller will drive my rear hub. It is expensive, but ideal for now. The guys at Grin tech are hub motor guys and their controller comes with a suite of support for when it comes time to program it for my ENC3000. I considered a BAC 2000, but I feel there is a risk I will struggle to pair it with my ENC 3000. Also, the phaserunner's lower power will be safer on my dropouts as well as generating less heat to satisfy the 4th design goal. (Though, I will use dual grin tech torque arms, so the BAC 2000 may be an easy option for an upgrade later). This controller will handle speedometer, as well.
Battery: 72V 32AH (litespeed)
Big voltage and capacity to make maximum use of my big triangle. 300 amp BMS means my 105 amps of draw (65A BAC 855+40A phaserunner) will never challenge the battery. It also leaves plenty of room to eventually upgrade the phaserunner to a BAC 2000.
Brakes: Shimano Hydraulic Disc Brakes with 200mm or larger rotors.
Fork? (Idk yet)
I want a stiff/high speed/high performance front suspension fork. Any recommendations?
Front wheel?
Once I figure out my fork I can figure out my front wheel. 17" or 19" motorcycle wheel would be great, but I don't know how to mount that to quick release drop outs so that may violate the first design goal. 24" or 26" plus size or fat size wheel may be what I end up going with. Then, I'd need to find fast tires for the wheels.
Throttle: right thumb throttle
No twist throttle means I can grip and rip the handle bars without accidentally pumping my throttle.
According to the system calculator at ebikes.ca this sort of setup should yield somewhere between 5kw and 6.5kw of power and 85-95 ft/lb of torque. The calculator tells me a top speed of roughly 50mph, but I think that is an under-estimation due to assuming too much drag and rolling resistance. My current ebike's top speed outperforms the ebikes.ca estimation by between 5 and 13 mph depending on riding conditions, so the 50mph estimation does not discourage me from my 60mph goal.
Please let me know your thoughts about my dream bike and help me make it a reality by enlightening my amateur ebike assembling mind.
In short: I want a fat mountain bike e-moto conversion with dual electric drive and no shifting (single speed).
Design goals:
It must be possible to assemble the bike from existing components in the market. Required handywork must not exceed wrenching, filing, and soldering. I don't have access to custom parts or a machine shop.
170mm rear drop out fat bike conversion build (from components, not from an existing bike)
Dual electric rear wheel drive: mid drive+direct drive rear hub (don't try to stop me, this element is non-negotiable)
Must be able to handle the heat generation of full throttle on a 10% grade from a full charge to nearly dead and then roll back down the hill with regen braking. Again, without risk of overheating. Assuming a 220 pound rider.
60 MPH top speed.
Single speed
No tubeless wheels
Frame: 18” Framed Minnesota 2.0/3.0
I built my current ebike on the 20 inch version of this frame. I love it. Huge triangle space. Rides great with the seat slammed. Very much like a mountain bike but fat. Sportier geometry, like a more acute rear angle, would be cool, but I do love this frame. Going smaller, 20" to 18", should yield a small gain in agility.
Rear direct drive hub and wheel: ENC3000
I've used this motor in the past on my current bike and I love it. It's 11.94 Kv, so it is a relatively fast winding. The primary reason for using this motor specifically is because Ncyclebike told me they could send me one with a 170mm compatible axle laced into a 19" motorcycle wheel. (I'm considering going 17" for less weight, more stiffness, more agility, and more torque). They also told me they could send me an 11 tooth single speed rear freewheel for it.
Mid Drive: CYC X1 Pro Gen 2
With a BAC 855, 12/72 gearing, and an 11 tooth rear freewheel. Disable/bypass PAS and spoke speed sensor.
Rear hub controller: Phaserunner
This controller will drive my rear hub. It is expensive, but ideal for now. The guys at Grin tech are hub motor guys and their controller comes with a suite of support for when it comes time to program it for my ENC3000. I considered a BAC 2000, but I feel there is a risk I will struggle to pair it with my ENC 3000. Also, the phaserunner's lower power will be safer on my dropouts as well as generating less heat to satisfy the 4th design goal. (Though, I will use dual grin tech torque arms, so the BAC 2000 may be an easy option for an upgrade later). This controller will handle speedometer, as well.
Battery: 72V 32AH (litespeed)
Big voltage and capacity to make maximum use of my big triangle. 300 amp BMS means my 105 amps of draw (65A BAC 855+40A phaserunner) will never challenge the battery. It also leaves plenty of room to eventually upgrade the phaserunner to a BAC 2000.
Brakes: Shimano Hydraulic Disc Brakes with 200mm or larger rotors.
Fork? (Idk yet)
I want a stiff/high speed/high performance front suspension fork. Any recommendations?
Front wheel?
Once I figure out my fork I can figure out my front wheel. 17" or 19" motorcycle wheel would be great, but I don't know how to mount that to quick release drop outs so that may violate the first design goal. 24" or 26" plus size or fat size wheel may be what I end up going with. Then, I'd need to find fast tires for the wheels.
Throttle: right thumb throttle
No twist throttle means I can grip and rip the handle bars without accidentally pumping my throttle.
According to the system calculator at ebikes.ca this sort of setup should yield somewhere between 5kw and 6.5kw of power and 85-95 ft/lb of torque. The calculator tells me a top speed of roughly 50mph, but I think that is an under-estimation due to assuming too much drag and rolling resistance. My current ebike's top speed outperforms the ebikes.ca estimation by between 5 and 13 mph depending on riding conditions, so the 50mph estimation does not discourage me from my 60mph goal.
Please let me know your thoughts about my dream bike and help me make it a reality by enlightening my amateur ebike assembling mind.