Mother's Day Musings - Kick-ass Mama E-bike

[Ravi Kempaiah]

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For the past 4 weeks, I kept thinking what would make an excellent gift to my mom or anyone's mother for that matter that would help them stay healthy.
If she can stay very healthy until whatever age God has given her, that would be a blessing.

20-30 minutes of biking per day can greatly reduce that number of knee and hip replacements.
And E-bikes make exercising fun!

Apart from that, females in the age group of <40 might also benefit greatly if they can find a very low-maintenance bike that is built from the ground up to be a high-quality machine.
So, we are designing this prototype. The goal is to build a very low maintenance bike that women (and men) can get on and ride.
Service will be handled through Velofix or local bike shops for which they will be reimbursed.

If you have any thoughts or feedback for improvement, I would welcome that.

CAD sketch, specs and anticipated pricing can be seen below.
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[YTOUY]

Ravi, this looks like a winner.
Good luck with the new venture.

 

[Deacon Blues]

Ravi, for older people who haven't ridden a bike in many years the enviolo automatic shifter looks to be a good choice.
My 63 year old wife, who was never much of a cyclist in her younger years, loves riding her ebike. What she doesn't like is shifting gears. Given the choice of shifting gears, even with the Rohloff Hub, or going fully automatic, she'd prefer the auto shifter.

I won't show her this post, because she may like this bike over the WW Superbike I ordered for her.

 

[Ravi Kempaiah]

The step is way too high.

Thanks for the pictures and feedback.

1. The second battery is optional. The default option is a powertube and the frame will have deep wave design.
   From the ground to concave arc in the frame near the motor, it is about 35cm (just above the height ~ 1 ruler length). Picture shows 29" wheels and that may change the visuals a bit.
   
   
2. This bike is not for disabled. This is for folks who are healthy and want to remain healthy or regain better shape/stamina.
   
   
3. There are not many Class 3 bikes with Gates drive in deep step-thru design for under $4000.
   
   
   

 

[TomD]

Have you experimented swapping the spare battery and water bottle locations? I wonder if that would make for easier step through with spare attached? It might also make things look more balanced with the spare battery attached, not sure.

 

[Ravi Kempaiah]

Have you experimented swapping the spare battery and water bottle locations?

Excellent observation, Tom!

That is what I have been working on. We need to source the right gusset and a different seat tube to be able to do that.
A support gusset is needed to maintain the rigidity of frame and we will have to figure out stealthy re routing of the second battery cable.

 

[Ravi Kempaiah]

Bolton puts water bottle right on where fork tube is.

We have mounting points near the headtube. Perhaps you missed it because it was so small on the CAD sketch.

There are two on each side. Could be used for a lock or water bottle.

 

[BlackHand]

That design looks nice, Ravi!

Given your mother's day theme, what's the anticipated minimum rider height? The average adult female is 63.6", and that kinekt seatpost really raises the saddle height...

 

[Solom01]

Interesting, but this looks more like a bike designed for the wives of the small number of bike enthusiasts instead of the general population. Living in Florida where there are a lot of older people I don't think anything would convince most older women to get on a bike. Besides the weather the bike infrastructure is horrible and the number of distracted, confused riders on the road makes biking dangerous. Assuming you could overcome that there's a reason why in the real world hub driven, throttle bikes vastly outsell middrive euro type bikes. They are a lot easier to use, quite reliable if good parts are used and the "push" feel of the hub drive is very pleasant for most people. As for the gearing assuming mutiple speeds are needed (in places like FLorida they're largely irrelevant) the last thing an older person wants is the complexity of multiple closely spaced gears. If the bike has enough reserve power even a simple three speed gear should be more than enough.

 

[Ravi Kempaiah]

That design looks nice, Ravi!

Given your mother's day theme, what's the anticipated minimum rider height? The average adult female is 63.6", and that kinekt seatpost really raises the saddle height...

Thanks for this observation. We have 3 sizing options. S-M-L. Very rarely you see a female rider who is 6ft+ , so for now, XL is not an option, may change in the future.
For shorter riders, 26" wheel be an option. This should make the small frame accessible for riders ~5ft.

Interesting, but this looks more like a bike designed for the wives of the small number of bike enthusiasts instead of the general population. Living in Florida where there are a lot of older people I don't think anything would convince most older women to get on a bike. Besides the weather the bike infrastructure is horrible and the number of distracted, confused riders on the road makes biking dangerous. Assuming you could overcome that there's a reason why in the real world hub driven, throttle bikes vastly outsell middrive euro type bikes. They are a lot easier to use, quite reliable if good parts are used and the "push" feel of the hub drive is very pleasant for most people. As for the gearing assuming mutiple speeds are needed (in places like FLorida they're largely irrelevant) the last thing an older person wants is the complexity of multiple closely spaced gears. If the bike has enough reserve power even a simple three speed gear should be more than enough.

Thank you.

A very nice hub drive is in the works. It is totally possible to build a nice hub drive with 48V, 17Ah battery for $1990.
The challenge is to test the motor + controller + torque sensing system and tune them for highest reliability. We will strive towards making that happen.

For now, Bosch system is chosen for several reasons:

1. Reliable system integration (Motor + battery+ controller + display has been thoroughly field tested).
   
   
2. Gen 4 systems have very nice torque sensing setup and features like app, upcoming NYON are all very nice additions.
   
   
3. Availability of spare parts.
   
   
4. Ability to couple with high-quality parts like Gates drive system, Enviolo or Rohloff.
   
   
5. End user service can handled easily as there are hundreds of shops with Bosch certified mechanics.

Since we are going after refined ride characteristics, Bosch or Yamaha is a natural choice. If we are going after power, a MAC motor would be outperform many of the mid-drives but reliability, service, design, aesthetics of the bike will be a point of concern.

But, as I mentioned, we will strive to get that hub design out on the market later this year or early next year.

 

[Ravi Kempaiah]

What she doesn't like is shifting gears.

Thanks for pointing this out. This is exactly the issue that makes people think Bosch bikes are under powered: they just don't know how to shift.

If someone has not ridden a bike for 30 years, a simple hub drive + throttle gets the quickest pathway to E-bike happiness (or addiction!) but there is a bit of learning curve for riding a mid-drive system properly.

Automatic shifting eliminates that problem for the most part.

 

[BlackHand]

Thanks for this observation. We have 3 sizing options. S-M-L. Very rarely you see a female rider who is 6ft+ , so for now, XL is not an option, may change in the future.
For shorter riders, 26" wheel be an option. This should make the small frame accessible for riders ~5ft

That's great to hear. Not enough smaller brands offer multiple frame sizes and wheel sizes. Thanks!

P.S. love the mounting points up by the stem, much more accessible for a lot of folks.

 

[Ravi Kempaiah]

Quite excited to see this come to fruition. Frames ready for painting

4th Gen Bosch motor - excellent reliability and speed
Gates belt drive - silent, super-low maintenance, long service life
Rohloff E-14 Internal gear hub -
1000 Whr Dual battery for all-day riding -
Step-thru frame for a kickass mama -

 

[Taylor57]

Quite excited to see this come to fruition. Frames ready for painting

4th Gen Bosch motor - excellent reliability and speed
Gates belt drive - silent, super-low maintenance, long service life
Rohloff E-14 Internal gear hub -
1000 Whr Dual battery for all-day riding -
Step-thru frame for a kickass mama -

View attachment 69308

What about kick ass papa?

 

[Ravi Kempaiah]

What about kick ass papa?

We have a separate thread for that particular bike and that frame is also ready for painting

 

[ExFire]

We have a separate thread for that particular bike and that frame is also ready for painting

L-L-L-L-Link?

 

[Ravi Kempaiah]

L-L-L-L-Link?

As we speak, it is getting painted in Ashland, OR.
I will share the pictures as soon as it's done.

 

[Ravi Kempaiah]

Testing is so important to offer a frame that performs even in the toughest conditions. It takes time but it is worthwhile in the long run.

 

[vincent]

very cool! cannot wait to see them after they are painted