Compact Electric Bike Design

[nimblemotors]

Been working on a compact electric bike and was wondering what things are important in a 'onshore transport vehicle' if I were to make a product from this effort.

I've been research bike designs, and it is truly amazing that a bike has been built by someone using just about every imaginable possible way to build 'personal transport vehicle'. From one-wheel pedal, gas and electric wonders, to four wheel wagons and wheel chairs and everything between.

The relative importance of the design features is what I'm wondering about.
Compactness, Price, Speed, Comfort, Durability, all somewhat conflict.

The 'standard' that marine supply houses sell to boaters is a 20in foldup bike.
I don't particularly like this setup, just seems to heavy and not compact enough.

What I've put together to test out is essentially an electric 'kick bike', something like this $480 product:

Cross Max Kickbike Scooter (Metallic Green) - Rakuten.com Shopping

With an electric hub motor in the front wheel and the batteries in the middle,
and have it disassemble or fold into a small package, made out of materials that will last in a marine environment.
My test bike is just cobbled together parts from old bikes.

My question would others be interested in a bike like this, and how would you rank the features in importance? Compactness more important than Price or Comfort? For example, small wheels are compact, but give a poor ride.
Durability and Price conflict as durable materials can vary dramatically in cost.

I appreciate any input.

[socaldmax]

I think I'd rather have something that looks like a regular 10 speed bike, but with a motor that's easy to engage/disengage. I think I've already seen a few that are exactly what I'm thinking about. With a rack on the back and lightweight canvas saddle bags, plus a medium or large backpack, one could get quite a bit of groceries/knick knacks each trip into town.

[delmarrey]

This is what I carry on the back of my RV. It'll last an EZ hour on flat ground and travels up to 15 mph, weighs just under 75 # and the handle bars fold down. it cost less then $400. The battery even lasted about 5 years. The new batteries were $70.
There are a lot of different brands and models to choose from.


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[ranger58sb]

Originally Posted by nimblemotors

The relative importance of the design features is what I'm wondering about.
Compactness, Price, Speed, Comfort, Durability, all somewhat conflict.

My question would others be interested in a bike like this, and how would you rank the features in importance? Compactness more important than Price or Comfort? For example, small wheels are compact, but give a poor ride.
Durability and Price conflict as durable materials can vary dramatically in cost.

Weight would be my number one criterion. I'm not lifting anything over 40 lbs, and 25 is better. Even if components have to be separable to accomplish it.

None of the other criteria matter for me, until weight is solved.

-Chris

[nimblemotors]

Originally Posted by ranger42c

Weight would be my number one criterion. I'm not lifting anything over 40 lbs, and 25 is better. Even if components have to be separable to accomplish it.

None of the other criteria matter for me, until weight is solved.

-Chris

I agree weight is important, particularly having to lift it from a locker or in/out of the dinghy. The design is to have it breakdown into 3 parts, the rear wheel, the center battery section, and the front wheel and handlebars. Won't really fold but disassemble.
I've changed it so the electric hub motor is on the rear wheel, which distributes the weight more equally between the three components.
I increased the rear wheel size to 16in.
Also going to make the throttle control wireless, so the handle bars have no wires to the battery section.

I'm thinking aluminum for the custom frame. With the motor in back, the front wheel, and handle bars can be off-the-shelf, so one could use carbon fiber components to reduce weight there.

[BandB]

Yike Bike:

YikeBike Models, Specifications and Materials | YikeBike - The world's first super light folding electric bike.

Ecobike Vatavio is nice but 50 lbs.

Nycewheels.com has a few different brands in the 43 lb range.

Or itemindustrialdesign.com for custom bikes.

Or get a Velomini at 36 lbs and you can even tow a trailer behind it. http://velomini.com/bikes

[nimblemotors]

As I mentioned, there are many many options. Almost NONE are designed to take the abuse of a salt-water environment.
The market for ocean bikes is tiny compared to general city commuters.
The best thing I have seen in my countless hours of research is the Stigo, 30 lbs and very compact. What is not to like? Small wheels on dirt, gravel or Mexican 'roads', not going to work, only 15mph too slow for me, not enough range either, and current price almost $3,000, and still not salt-water friendly. Folders mean having to lift the total weight, whereas with a disassemble design means lifting-moving smaller 15 lbs parts.
And where is the basket to carry groceries?
BTW, the Yike is a good example of how just about everything has been tried, no matter how dorky or impractical!

[BandB]

Originally Posted by nimblemotors

As I mentioned, there are many many options. Almost NONE are designed to take the abuse of a salt-water environment.
The market for ocean bikes is tiny compared to general city commuters.
The best thing I have seen in my countless hours of research is the Stigo, 30 lbs and very compact. What is not to like? Small wheels on dirt, gravel or Mexican 'roads', not going to work, only 15mph too slow for me, not enough range either, and current price almost $3,000, and still not salt-water friendly. Folders mean having to lift the total weight, whereas with a disassemble design means lifting-moving smaller 15 lbs parts.
And where is the basket to carry groceries?
BTW, the Yike is a good example of how just about everything has been tried, no matter how dorky or impractical!

First time I knew of a Yike was Jarrod and Brandi found one in a storage locker on Storage Wars and were shocked to find out how much it was worth.

[ranger58sb]

Originally Posted by nimblemotors

And where is the basket to carry groceries?

Ah, yep, forgot to mention: load-bearing capability is my second criterion.

One of our current bikes is a Downtube suspension model... but only front suspension, so the rear is rigid with a luggage rack. Easy to zip-tie a small milk crate to it for groceries, ice, beverages, etc. Snap-on pouch for the handlebars will hold a little. All augmented by my backpack when absolutely necessary.

-Chris

[Dockhead]

An electric bike with the right qualities would be a real boon to cruisers -- a kind of land tender.

But I don't think the "right qualities", at least as I understand them, are attainable with the present state of technology.

My present "land tender" is a Dahon Jetstream EX folding bike. It is too heavy (20 pounds) and bulky even for a 54' boat, not to even think about two of them. But I need it, so I sacrifice a large part of my precious deck storage (lazarette) to it. The weight and bulk affect not just storage on board, but also carrying in the water tender to shore. I have a large (3.4 meter Avon RIB) tender, but the one bike pretty much takes up half the dinghy.

So although electric propulsion would be nice, I wouldn't consider it if it meant that the bike would be even heavier and bulkier than what I have already.

So purely theoretical discussion -- just dreaming -- but what I would personally like to see:

1. Very light and folds up very compact -- I would pay a lot of money if this were possible.

2. Probably needs 20" wheels; certainly not less than 16". I'd rather pedal a bike with 20" wheels than ride an electric with 14" wheels or whatever.

3. Regenerative braking.

4. Good stiff frame and decent pedal gear -- electric propulsion is no good if you can't pedal it.

5. Personally, I would be ok if the electric drive mechanism is sized more to give assist up hills, than to drive the bike continuously. The hill assist is key for middle-aged cruisers hauling carp to the boat, but I don't think most of us mind pedaling in other circumstances.

[Cotemar]

Light and compact will win any cruisers heart for a boat bike.
20 lbs is a good weight that a woman can carry.
Compact, so you can fit two of them in a 10 foot dinghy with two adults.
E-TWOW

[BandB]

Originally Posted by Cotemar

Light and compact will win any cruisers heart for a boat bike.
20 lbs is a good weight that a woman can carry.
Compact, so you can fit two of them in a 10 foot dinghy with two adults.
E-TWOW

The 8" wheels on that scare me. But then I don't have the greatest scooter type balance. I just imagine feeling like a giant riding a small kid's toy.

[nimblemotors]

It is always possible to make one more compact by having tiny wheels,
make it lighter by having tiny motors and tiny batteries.
All these design factors make the result have limited usefulness.


I get that weight is important, and have addressed it by breaking down the bike into 3 small lightweight parts, each part is lighter than the 20lb scooter!

Having pedals adds a large amount of complexity and weight and bulk that is not necessary if the motor and battery is big enough (in my opinion).
This adds a lot of cost vs pedals, but I think this is the right tradeoff,
cost more and get more compact and simpler.
The current front wheel is 24in, and as my pic shows, this looks like a bike, not a kids toy.