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Discussion Starter · #1 · (Edited)
First, let's define ...
Human power?

According to "NASA 1964", a "Healthy man" is capable of:
About 200 watt sustained for 30 minutes
About 150 watt sustained for 60 minutes
100-150 watt seems a reasonable sustained "human assist" on an eBike! ... ?

I, personally, would like to sub-categorize "eBikes", into 3 categorizes.

1. eaBikes - electric assist bikes
<750 watt output motor ?
Healthy man is capable of sustaining 20%, or more, of the eBikes propulsion

2. eBikes - electric bikes
>750 watt output motor ?
Where healthy man is capable of reasonable contribution - but, essentially, only during limited throttle use.
Due to wind resistance, a tucked position increases range, better than a "proper" pedaling position.
Somewhere near 30 mph, the cyclist, (<10-15% contribution), is detrimental, to speed and range, compared to a more aerodynamically positioned, (non-pedaling), rider.

3. eMotorcycle - incapable of any "reasonable" % pedal assist
Pedals are "ornamental", if they even exist!

Note: 750w (watt) = 1hp = USA, Federally recommended, eBike limitation.
 

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Discussion Starter · #3 · (Edited)
Speed?

I, personally, would like to sub-categorize "eBikes", into 3 categorizes.

1. eaBikes - electric assist bikes
<750 watt output motor ?
Healthy man is capable of sustaining 20%, or more, of the eBikes propulsion

2. eBikes - electric bikes
>750 watt output motor ?
Where healthy man is capable of reasonable contribution - but, essentially, only during limited throttle use.
Due to wind resistance, a tucked position increases range, better than a "proper" pedaling position.
Somewhere near 30 mph, the cyclist, (<10-15% contribution), is detrimental, to speed and range, compared to a more aerodynamically positioned, (non-pedaling), rider.

3. eMotorcycle - incapable of any "reasonable" % pedal assist
Pedals are "ornamental", if they even exist!
A simpler, and probably better, classification might be based on speed capability.
For example ...

1. eaBikes - 20mph top speed (motor only)
Federally recommended to be treated and classified as a bicycle.

2. eBikes - 30mph top speed (motor only)
Since this would be capable of "in traffic" travel, head, turn and brake lights might be recommended-required.

3. eMotorcycle - >30mph top speed (motor only)
Lights, inspection, registration, insurance should be required.
 

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Discussion Starter · #4 ·
eaBikin' - Pump It Up!

I would rate, most all, pre-built eBikes as eaBikes. (electric assist Bikes)
Most are limited to 20 mph, and all, seem to, require pedal assist to attain "reasonable" range - 20miles?

Happily, "stretching" the top speed and range can be interesting ... and fun.
I set my personal goal at 30mph, that allows me to meld smoothly, with local traffic.
Typically I "cruise" at about 20mph, great for most of my commuting routes, trails, paths etc., but there are unavoidable sections of 30mph "heavy traffic". The only "safe" options are to match their speed, or wait on a side street till they get a red light, then "hump it" to keep ahead of them for several blocks (a nice morning workout!).
"Pushing" a 20mph eaBike to 30mph can be reasonably easy and moderately safe, pushing designed capability to 150% seems acceptable if offset by load capacity reduction, below ~250lb capacity rating. (165lb rider?)

Honestly ... I fear for the builders, pushing their oem bikes towards 40-50mph+ capabilities.
That exceeds the designed capabilities by an outrageous degree.
Most recognize this and spend a "comparative fortune" on upgrading components!
But the build is only as safe as the weakest link ...

I have nothing against, even, highway speed capability.
It just seems, much safer and cheaper to rebuild a motorcycle as an eMotorcycle.
Tires, brakes, frame, suspension ... every component is designed for the weight, power and speed!
While a 40-50mph eBike might not be considered as street legal ... most anywhere! ... ?
A motorcycle "eConversion" gives you a Title, Registration, VIN number, everything you need for legal street use, including Insurance!

Trust me, if you are ever in an "incident" with a "hopped up" eBike build, you will want insurance!
 

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Discussion Starter · #5 · (Edited)
Starter eBike

Like many, I began my quest into the arena of eBikes with an eZip Trailz.
eZip Trailz - On Sale!
Being what I consider a "starter eBike" it is, comparatively, very affordable.
2008 eZip Trailz cost me $300ish.
15 mile range w/pedal assist.
16mph motor only speed with some assist to 18mph.

Being so cheap, I didn't expect much in the way of performance or durability.
But, in it's 4th year (4000+ miles) my Trailz is still going strong!
This received 2 major enhancements.
1. 20mph+ from EZIP 24 volt OEM pack! $20 upgrade!
2. I designed and built 25.9V Li-ion battery packs, by recycling laptop batteries!
40-50 mile range (@16mph oem speed) and 1/2 the weight of the oem battery!

I got a 2nd eZip, an eZip Mountain Trailz, and upgraded it, from 24V to 36V.
Big advantage was that it increased my speed, from 16mph to 23mph.
After I built a 37V Li-ion for this I really started piling on the miles.
3500 miles+, so far, and I ran it through the last 3 Winters.
Check out my thread on building your own studded tires.
Studded Tires!



I've done other enhancements and have plans ...
30mph capability.
Modified spoke methodology - added strength & durability.
Regearing for high speed assist, rather than optimal motor only speed.
Adult tricycle econversion.
Adult tricycle "mobility" econversion (with forward\reverse etc.)
7 speed eBike conversion w/shifting buffer

Stay tuned for more ...
 

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retromike3
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Definitions and reality check

Until very recently I had a motor assisted bicycle. the bike was an old Scott mountain bike that i converted over to use with a small two-stroke motor. Since I build bike frames as a hobby I replaced the rear dropouts with track bike ends with a rear derailleur hanger so I could put tension on the motor chain. I also modified the front fork and set it up so that it had a much more relaxed head angle.

Even with a "tuned pipe" and a better rear drive cog the top speed I got under power was around 27 miles an hour.(according to my iphone) Since I was going to school downtown and I had to get over a fairly steep hills and since I am simply too beat up to ride like I used to, having that little motor really helped me out a lot.

The neat thing about the system I was using was that the motor was an option. As soon as I got close to campus I would simply turn the motor off and pedal in. I could then park the bike at the bike stands and I wouldn't have to worry about paying the exorbitant fees that that they charge for the motor parking.

I figured out that i was getting about hundred and twenty miles to the gallon. which is a pretty good system I think.

The way these things work is that you have to pedal them about fifteen miles an hour before you can pop the clutch to get them started and as I stated before, typically if I came up to a place where I thought that the motor would be obtrusive I would simply go into "stealth mode" and just pedal the bike.

I set up the rear freehub with a eight speed 11/32 cassette and in front I had a single 36 chainring. That gearing made it possible that if my motor quit I could still get there on my own.

I also made it a point to ride my bike responsibly regardless of motor assisted or not and I always wear a helmet and do stupid things like turn signals just to be sure.

The main thing I got out of that bike was the freedom to go were I needed to without having to find a shower and a fresh change of clothes when i showed up.

mike
 

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Discussion Starter · #7 ·
Gas MPG vs Electric MPGe

Until very recently I had a motor assisted bicycle. the bike was an old Scott mountain bike that i converted over to use with a small two-stroke motor. ...
I figured out that i was getting about hundred and twenty miles to the gallon. which is a pretty good system I think.

mike
Much better than a car but ...
My eZips run on a 450w DC motor (0.6HP).
My larger Li-ion pack is a 25.9V x 31.2Ah (0.8 kWh), and lets me, motor only, cruise +35miles @ +20mph. (43.75 miles per kWh)
(USA June 16, 2012 prices)
With gas at $4.16 and electricity at $.11 per kWh. (37.8 kWh per gallon gas, by cost)
37.8 kWh x 43.75 miles per kWh = 1653.75 MPGe

Sadly, wind resistance is a bitch.
Upgrading to, a motor only, 30mph will drop economy to 1000 mpg, possibly worse!

Yes, I do intend on experimenting with simple front fairing designs.
Full fairing designs have produced 80mph pedal only speeds!
While I don't intend on motoring at 80 mph, a simple fairing might double my fuel economy ... 2000-3000 MPGe!

PS. A test run, 16mph economy mode cruise produced 50 miles per .8kWh = 2362.5 MPGe.
 

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Discussion Starter · #8 · (Edited)
eaBike

I've come to favor eaBikes.
Power applied when wanted for hills, acceleration, higher sustainable speed etc.

Optimal motor would be a geared, permanent magnet, front hub brushless motor.
Brushless is noticeably more efficient ~90%
Permanent magnet is is very noticeably more efficient
Geared, typically involves a freewheel so there is not the "drag" of the DD (Direct Drive) hub motor, when not powered
Front hub allows normal access to all sprocket gearing options (rear hubs are typically limited to 5-6 sprockets)

Further, motor should be optimized for type of assist.
By varying voltage and controller amperage, it is possible to customize the torque and efficiency profiles.
 

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I would get lazy with a motor. When I ride the Prairie, sometimes (less and less now) I have to take breaks. If I had a motor to turn on, I would not take those breaks and then get the extra benefit of going up the hard to climb hills, those forever lasting inclines, that have helped me get in shape and taken pounds off my body.
 

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Discussion Starter · #11 · (Edited)
I would get lazy with a motor. When I ride the Prairie, sometimes (less and less now) I have to take breaks. If I had a motor to turn on, I would not take those breaks and then get the extra benefit of going up the hard to climb hills, those forever lasting inclines, that have helped me get in shape and taken pounds off my body.
I got my 1st eBike back in 2008 because I was badly out of shape.
Poor heart and and respiratory function.
I felt like dying after a few minutes trying a Mountain bike.

Anyhow, got the eBike and began "cycling" everywhere, pedaling constantly with moderate throttle use.
Rather than relying solely on the motor, I relied less and less upon it.
So much so that I regeard the eBike to provide less assist ... but to increasingly higher speeds.

I built multiple eBikes designed to motor only at the US "legal" 20mph limit, took up to speed, released throttle then maintained 20mph by pedal only for 1 mile stretches, recovered with applied motor assist, then pedaled another mile etc.
The eBike rehabed me from a wheezing shuffling 49 year old old man into a reasonably healthy 55 year old youngster. Was eventually able to sustain 20mph for my 8 mile morning jaunt around the local MUP - pedal power only.

Most all of my builds are designed and built as eaBikes (electric assist Bikes) not as eBikes (electric Bikes) ... to assist and enhance the cyclist in me ... not replace him.
 

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Discussion Starter · #13 · (Edited)
Cardiovascular Workout

Have you considered trying a human powered vehicle now that you've regained fitness?
Oh ... yeah ...
Got a nice 2010 Haro Express Deluxe that I take 10 mile pedal only jaunts with ...

Optimal cardiovascular workout is 30 minutes of sustained moderate workout.

About ½ mile of cautious steet then 8½ miles of reasonable level MUP, back to ½ mile of street gives me a warm up - workout - cool down ... optimal.

I did build a quick swap 700C motor capable wheel for the Haro.
5 min quick conversion from Bike to eaBike ... and back.

But even my eZips are excellent pedal only bikes ... unlock the battery from the rack and go ... but my 1kWh battery build is only about 10lb.

See - Haro Express Deluxe Conversion

Much of the "upper management" is actively anti-eBike and hostile towards any mention of eBikes.

I have decided to ally with them and help rid this forum of those interested in, or in need of, electric assist.
There are much better forums for eBikers.
Most progressive seems to be endless-sphere.com they are the premier advocates for promoting eVehicle, including eBike, development. Bonus = no advertisements!!!
Also of respectable provision and intent is bikeforums.net

 
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