Search found 159 matches

by cerewa
Jun 01 2008 1:41pm
Forum: E-Bike General Discussion
Topic: what motor/system to buy?
Replies: 7
Views: 1011

what motor/system to buy?

A friend of mine wants an e-bike. She can pedal, but not very strongly due to a knee injury. She has never ridden an e-bike. I suspect the setup that would work best for her would give its best performance at 10 to 15 mph and have lots of torque for steep hills. Any hub motor under 600W is probably ...
by cerewa
Jun 01 2008 1:26pm
Forum: E-Bike General Discussion
Topic: electric bike from 1993 !
Replies: 3
Views: 531

Re: electric bike from 1993 !

The change in the last fifteen years is a lot more social and political than technological, with the exception of batteries.
Brushed motors and SLA batteries have been around a lot longer than 15 years, I can tell you that. :D
by cerewa
May 31 2008 6:32pm
Forum: E-Vehicles General Discussion
Topic: *** Club For Extreme Battery Range ***
Replies: 45
Views: 4069

Re: *** Club For Extreme Battery Range ***

Here's my pack:

$330, YESA 24V10Ah LiFePO4 pack - about 250 miles @ 50% pedal power, and in perfect shape - but my motor controller doesn't work right
by cerewa
May 31 2008 8:26am
Forum: E-Bike General Discussion
Topic: Ebike Relay Charging Stations
Replies: 29
Views: 2351

Re: Ebike Relay Charging Stations

Great idea. 5. Do I need to specify maximum power drain (watts)? or (Kwatthours). People providing outlets should be asked to specify the available amperage for the circuit breaker the outlet is on before folks decide whether to charge there. I get the impression single family homes in the USA (I do...
by cerewa
May 31 2008 8:16am
Forum: Battery Technology
Topic: Yesa vs Ping packs
Replies: 7
Views: 1084

Re: Yesa vs Ping packs

I didn't know about Ping packs when I bought my 24V10Ah pack from Yesa.

In my experience yesa's quality is good, but I'd buy more watt-hours for the same price if I could.
by cerewa
May 20 2008 8:49pm
Forum: E-Bike Technical
Topic: Multiple Cyclone Motors
Replies: 19
Views: 1851

Re: Multiple Cyclone Motors

One of the things that the efficiency curves don't show is what kind of efficiency you get at below-full throttle. My subjective impression is that the 500W cyclone motor (which i have) runs very efficiently if you avoid running it at full throttle. All that extra copper (compared to the 360W versio...
by cerewa
May 20 2008 8:46pm
Forum: E-Bike Technical
Topic: Aero e-bike concept
Replies: 35
Views: 8396

Re: Aero e-bike concept

I've thought about this sort of beast for a long time. If you want a power to weight ratio like a car, you will need two x5 motors but if you don't mind having all the acceleration/hillclimbing of a bus (or of a Prius that's being driven for top fuel economy) you can go with just one motor. Using on...
by cerewa
May 20 2008 8:32pm
Forum: E-Bike Technical
Topic: .
Replies: 27
Views: 2166

Re: Gearing a Mountain bike for road

If you have a non indexed shifter (or install one) then any bike that can handle a MTB triple should be able to handle a road triple, a road double, a road double used as a single (just leave it in the big gear), whatever. Do not use a chainring designed for a track bike - single speed chainrings ar...
by cerewa
May 14 2008 11:23pm
Forum: Battery Technology
Topic: battery voltage vs AC voltage
Replies: 7
Views: 546

Re: battery voltage vs AC voltage

If chargers were smaller, lighter, and created less heat when in use, you could attach your charger to your battery like it's part of your BMS, and just plug your battery in to the wall whenever you feel like. Less fooling around with separate parts. Easier to charge away from home, at a cafe, at a ...
by cerewa
May 14 2008 5:55pm
Forum: Battery Technology
Topic: battery voltage vs AC voltage
Replies: 7
Views: 546

battery voltage vs AC voltage

All of the battery chargers I have seen use a step-down voltage converter of some sort in order to efficiently charge the battery. I don't think it would save all that much, but I'm sure you could save a little bit of electricity by dispensing with the converter entirely and just using diodes to tur...
by cerewa
May 14 2008 5:35pm
Forum: E-Bike Technical
Topic: Hands off oscillation - what gives?
Replies: 30
Views: 2501

Re: Hands off oscillation - what gives?

Is this a motor that actually operates when the hands are off the bars? If not, the change in the hub's resistance to forward motion as the permanent magnets pass by the would seem to be a likely explanation. If not - the contact patch (where rubber meets road) is actually BEHIND the spot you would ...
by cerewa
May 14 2008 8:14am
Forum: E-Bike Technical
Topic: Brain Teaser: 72V set-up and 48V set-up Throttling
Replies: 12
Views: 886

Re: Brain Teaser: 72V set-up and 48V set-up Throttling

If i get this right of what he said. I one spun there motor up free wheel and say it spun to 50mph, and with a load on it at full throttle it only went 30 then your motor and controller combo ain't right and your wasting power. He said you need to be in the 10 mph ball park at be energy efficient f...
by cerewa
May 13 2008 9:45pm
Forum: Alternative Energy
Topic: free energy
Replies: 77
Views: 6674

Re: free energy

In linguistics, it makes sense to say that the definition of a word is whatever a bunch of people think the definition is. But the trouble with applying that idea to this "theory" business is that, just because one thing gets called a theory and another thing gets called a theory doesn't mean they'r...
by cerewa
May 13 2008 9:38pm
Forum: E-Bike Technical
Topic: Buy a new bike - sell mine, buy a steel framed?
Replies: 22
Views: 1804

Re: Buy a new bike - sell mine, buy a steel framed?

I'm confused. Why open-ended wrenches instead of closed (circle) ended wrenches? Is the axle the wrong shape for the closed ones?
by cerewa
May 10 2008 11:33am
Forum: Battery Technology
Topic: EEStor ultracapacitor
Replies: 181
Views: 15767

Re: Zenn gearing up for EEStor-powered car

What I want to see is a reasonably priced e-bike "battery" that charges in 5 minutes and is 10 times lighter than SLA batteries.

Who knows, it might happen. Might not.
by cerewa
May 10 2008 11:29am
Forum: E-Vehicles General Discussion
Topic: Another thread on frames: 700c
Replies: 11
Views: 1503

Re: Another thread on frames: 700c

the ratio of speeds you will get on 700c compared to 26 inch is about 27 to 26 (700c tires are about 27 inches in diameter, less for skinny tires). In my opinion, suspension is NOT the way to go but fat (non knobby) tires at somewhat low pressure are good - you do want a little bit of cushioning for...
by cerewa
May 10 2008 9:43am
Forum: E-Vehicles General Discussion
Topic: Questions about building an e-bike
Replies: 11
Views: 1687

Re: Questions about building an e-bike

so you would need to carry around 30% more fuel No you wouldn't. 9%: The volumetric energy density of biodiesel is about 33 MJ/L. This is 9 % lower than regular Number 2 petrodiesel. To run straight VO (veggie oil), you need to heat it to ~200F before passing it through the injection pump. I think ...
by cerewa
May 10 2008 8:55am
Forum: E-Vehicles General Discussion
Topic: 100MPH DOT RATED WHEEL TIRE???
Replies: 16
Views: 2849

Re: 100MPH DOT RATED WHEEL TIRE???

That bike is freakin Awesome! Nice job on it! Did you do everything yourself? Do you have street tags on it or is it still a "bicycle" by law? Ask your lawyer - If it's got no pedals, i'm pretty sure it ain't a bicycle. In the mean time you could call it an off road vehicle - just about anything th...
by cerewa
Apr 16 2008 7:12pm
Forum: E-Bike Technical
Topic: 24 volts from 2*36 v. batteries?
Replies: 4
Views: 591

Re: 24 volts from 2*36 v. batteries?

The dewalts are made out of individual 3.3V cells, which means if you use them in a 7 series setup they're about 23V and if you use them in a 8 series setup they're about 26V. (the 24V motors are designed to handle SLA batteries that give voltages in actual use between 20V and 26V or so, and any bat...
by cerewa
Apr 15 2008 8:03pm
Forum: E-Bike General Discussion
Topic: FrontWheelDrive dual-hubbed KMX
Replies: 30
Views: 5531

Re: FrontWheelDrive dual-hubbed KMX

did you mention the disadvantage that a trike with two hubmotors is going to be heavy? Probably weigh double what my lightweight e-bike weighs. :)
by cerewa
Apr 02 2008 10:23pm
Forum: E-Bike General Discussion
Topic: Gas $3.45 a gal.; charge your e-bike 3 cents
Replies: 28
Views: 3424

Re: Gas $3.45 a gal.; charge your e-bike 3 cents

You can calculate it, but it's better to know the reality. I use a "Kill a Watt" meter ($25). By my calculations, it would take me several years to use $25 worth of electricity (at about $7 per year). I think I'll pass on the meter that tells me how much I'm actually using. My battery is rated at 2...
by cerewa
Mar 26 2008 7:16pm
Forum: E-Bike General Discussion
Topic: What is the best way to protect your eBike from theft...
Replies: 42
Views: 4538

Re: What is the best way to protect your eBike from theft...

how bout a paint grenade.... that's been what I wanted to have as bike security for a while. NOt quite sure how to implement it though.

I'm not sure whether covering your thief in bright paint would stop them, but it might.
by cerewa
Mar 25 2008 6:02pm
Forum: E-Bike General Discussion
Topic: Cyclone-USA in business?
Replies: 9
Views: 1216

Re: Cyclone-USA in business?

one of the advantages of cyclone taiwan is that their prices are lower.

cyclone usa is an authorized reseller for cyclone taiwan, but I don't think there's really a lot of connection between the taiwan and usa companies.
by cerewa
Mar 24 2008 8:12pm
Forum: E-Bike General Discussion
Topic: Cyclone-USA in business?
Replies: 9
Views: 1216

Re: Cyclone-USA in business?

I think it's much better to deal with cyclone taiwan. (I got my kit from cyclone taiwan and then bought a replacement motor from cyclone usa when i destroyed my motor by running it full of water). cyclone-tw didn't ship all that soon after I ordered. it took them at least a week, but they warned me ...
by cerewa
Mar 24 2008 7:18pm
Forum: E-Bike General Discussion
Topic: Cyclone-USA in business?
Replies: 9
Views: 1216

Re: Cyclone-USA in business?

I've dealt with cyclone-usa. He shipped my order about 3 weeks after I put it in. One day after I ordered, he sent me an e-mail saying he would ship in a week. On a saturday 3 weeks after I made my order, I called the credit card company (after several "hey please ship my order" e-mails to cyclone) ...