Lately when I see questions coming up frequently, I've been clicking on the KB to see if it has responsive info. If it's not there, I look to see if there's a stub for the subject. Questions come up regularly about choosing a donor bike or frame for an ebike project. Since I didn't see a stub in the KB for this, I'm going to try to cobble together enough information to create an entry on the subject. I'm going to start with frame materials, listing some of the pros and cons, and then some stuff on frame geometry as if related to building an ebike, and any considerations.
I'd appreciate any input regarding this subject. The build thread subforum as been a good resource, but things like carbon fiber frame builds are a bit sparse, but there have been some successful builds using carbon frames, so even though I currently state "mid drive generally not recommended", I do think I noticed a successful mid drive carbon build, but not much insight into the long term durability, so I'm hoping some folks can speak to that based on experience. The threads are good since they demonstrate how the challenges along the was were addressed. Experience on things like the amount of flexing materials can withstand when chain stays are spread to accommodate a hub motors, etc., would also be helpful. The frame geometry section is meant to capture how it relates to ebike conversions, rather than personal preferences, comfort, etc.
Anyway, below is how I'm trying to gather material, while keeping it segregated to make it easier to post in the KB when complete. Thanks ahead of time for any input you can share.
Frame material:
ES Builds:
I'd appreciate any input regarding this subject. The build thread subforum as been a good resource, but things like carbon fiber frame builds are a bit sparse, but there have been some successful builds using carbon frames, so even though I currently state "mid drive generally not recommended", I do think I noticed a successful mid drive carbon build, but not much insight into the long term durability, so I'm hoping some folks can speak to that based on experience. The threads are good since they demonstrate how the challenges along the was were addressed. Experience on things like the amount of flexing materials can withstand when chain stays are spread to accommodate a hub motors, etc., would also be helpful. The frame geometry section is meant to capture how it relates to ebike conversions, rather than personal preferences, comfort, etc.
Anyway, below is how I'm trying to gather material, while keeping it segregated to make it easier to post in the KB when complete. Thanks ahead of time for any input you can share.
Frame material:
Steel
Pros:
Cons:
Motor: Suitable for hub drive or mid drive motors
Aluminum
Pros:
Cons:
Motor: Suitable for hub drive or mid drive motors
Carbon Fiber
Pros:
Cons:
Motor: Suitable for hub drive, mid drive generally not recommended
Frame geometry:Key considerations:
Battery mounting/placement - Ideally a frame with an "open triangle" provide the greatest ease and flexibility from battery mounting. Because the battery is a heavy component, placement lower on the frame keeps the center of gravity lower, and affects handling less. Other locations include under the frame downtube, provided there is enough clearance if the bike uses a suspension fork and the mounting is secure (additional straps may be necessary since bottle cage mounts may no provide the necessary strength, etc.). Mounting on a rear rack is also an option, but even very strong racks can be subject to fatigue over time and fail, so should be regularly inspected.
Hard Tail
Pros:
Cons:
Full Suspension -
Pros:
Cons:
ES Builds:
