Search found 767 matches

by jag
Feb 03 2011 10:59am
Forum: E-Bike General Discussion
Topic: Re: Ebike Kit, Batteries And Trailer
Replies: 24
Views: 2629

Re: Ebike Kit, Batteries And Trailer

It sounds like you don't have much ebike experience. If at all possible try some ebikes before putting lots of money into buying a building a high end one yourself. Cell_man's recommendations are good, but with some experience everyone finds little things they would have done differently. Personally...
by jag
Feb 02 2011 10:14pm
Forum: E-Bike General Discussion
Topic: A machine that is screaming for an electric motor.
Replies: 13
Views: 1529

Re: A machine that is screaming for an electric motor.

Note cop who shows up at about 4 min into streetflier video.
[youtube]LWxfxo1SdpA&NR[/youtube]

http://www.youtube.com/watch?v=LWxfxo1SdpA&NR=1
by jag
Feb 01 2011 10:44pm
Forum: General Discussion
Topic: Big winter storm - backup power question
Replies: 14
Views: 867

Re: Big winter storm - backup power question

Q1: Is the inductive load of a 24V transformer (similar to a doorbell xformer) incompatible with a typical computer UPS? Q2 is there a mod or alternative to make the transformer/UPS play nicely?[/list] Many computer UPS chop DC directly into 60Hz square wave, then use a big transformer to step it u...
by jag
Feb 01 2011 12:29pm
Forum: E-Bike General Discussion
Topic: Quest for "super stealth"
Replies: 35
Views: 4866

Re: Quest for "super stealth"

I live in an area with lots of hills/mountains, many 10% to 20% inclines, but, apart from hill climbing, my main priority is to not attract attention either audibly or visually - "super stealth". Builds just started: Bike 4. Two wheel drive Two 350W geared hub motor kits have arrived from cellman. ...
by jag
Jan 31 2011 9:51pm
Forum: E-Bike General Discussion
Topic: Best Deal on a Magic Shine Headlight only?
Replies: 8
Views: 754

Re: Best Deal on a Magic Shine Headlight only?

FYI: I just tried to order from geomangear to my address in Canada. The site seemed set up for worldwide orders, but somehow it choked on my Canadian address. Anyone else had l8uck? What are their typical shipping rates? On Deal extreme: The Magicshine with the presumably not-so-good battery is $77 ...
by jag
Jan 29 2011 7:10pm
Forum: E-Bike General Discussion
Topic: Magicshine Light Help -- Kit or just light?
Replies: 19
Views: 1527

Re: Magicshine Light Help -- Kit or just light?

I'm reposting Adrian's note about Eastward and Magicshine lights form the motor review thread below. Wonder if the different reflector design in the Eastward makes it less desirable? Some comments: The Magicshine runs off (afaik) 2s2p (or is it 4s??) , and I understand some people run it off 12V con...
by jag
Jan 28 2011 6:06pm
Forum: E-Bike Technical
Topic: BLDC Efficiency at different voltages
Replies: 63
Views: 2787

Re: Efficiency at same speed, different voltage.

Hi all, I'm building up a 9x7 9C to run on lipo with a Lyen 12 FET controller. My in-frame battery box holds 6 6S packs (zippy 5ah 15c) and I'm looking to use the bike to travel 18km each way to work. I believe if I run the motor with batteries wired 2s3p (nom. 44.4V) I will do about 40kph, which i...
by jag
Jan 28 2011 11:19am
Forum: E-Bike General Discussion
Topic: How cold is too cold for your motor?
Replies: 36
Views: 3490

Re: How cold is too cold for your motor?

Motor gears and bearings are lubed with grease. The grease gets stiffer and works poorly at very low temps. The lowest working temp varies with type of grease. Unfortunately eBike and bike products aren't labeled with type of grease or made with low temps in mind. With proper grease temps as low as ...
by jag
Jan 27 2011 11:17am
Forum: E-Bike General Discussion
Topic: Magicshine 900 Lumens MJ808 kit for $38?
Replies: 11
Views: 1284

Re: Magicshine 900 Lumens MJ808 kit for $38?

Reviews for Magicshine MJ808 mentions Light output less than advertised, but still good light output for the price. Battery issues (1/2 the run time of advertized) and some pages say under recall. (Again maybe likely battery). See mtbr: http://reviews.mtbr.com/blog/magicshine-mj-808/ http://reviews....
by jag
Jan 26 2011 10:57pm
Forum: E-Bike Reviews & Testing
Topic: 1000 watt Aotema Maxi-Might Cooked
Replies: 89
Views: 12488

Re: 1000 watt Aotema Maxi-Might Motor Kit Test

rebelpilot wrote:Update.

I will be testing this weekend, maybe even logging the CA data with my N800.
Do you have a data logging program for the Nokia n800? I searched briefly on google, but didn't find anything relevant looking on the first page of hits.
by jag
Jan 25 2011 11:12am
Forum: Large EV General Discussion
Topic: Open Source Controller - 144v 500 amps
Replies: 17
Views: 3604

Re: Open Source Controller - 144v 500 amps

I'm of the view that controller designers have thought too much about the DC issues, like Rdson losses and associated junction to ambient thermal conductivity problems, and have only paid lip service to the need for clean gate drive and proper RF type layout of the drive signal path. One look at th...
by jag
Jan 24 2011 10:43pm
Forum: Motor Technology
Topic: 40kW motor?
Replies: 23
Views: 3983

Re: 40kW motor?

So, I'm thinking about buying one, but what is up with this 280euro tax BS on top of a $2300usd motor? That's the VAT tax. You won't be charged that when they ship it for export, but look out for US import duties and UPS brokerage fees of at least similar amounts... kV seems a bit unpractical unles...
by jag
Jan 24 2011 10:34pm
Forum: E-Bike Technical
Topic: DIY Balance charger using IC chargers ???
Replies: 2
Views: 678

Re: DIY Balance charger using IC chargers ???

They are not isolated, so you could not series the output for several cells. They are also surface mount and require a few components around them. Wall warts are far easier to modify than to build these correctly (have to add an isolation PSU/transformer before each). Alternatively, convince some wa...
by jag
Jan 23 2011 10:03pm
Forum: Alternative Energy
Topic: My place
Replies: 3
Views: 882

Re: My place

Nice design! Especially the way you adapted it to the slope. Congrats on coming to a close with an ambitious building project. The amount of effort and dedication needed to do things yourself is rare nowdays. I like the first pics best, the garage door the least, but I guess a 2 car garage door ups ...
by jag
Jan 23 2011 7:33pm
Forum: Large EV General Discussion
Topic: Open Source Controller - 144v 500 amps
Replies: 17
Views: 3604

Re: Open Source Controller - 144v 500 amps

Looks like this is the main page for this project. http://ecomodder.com/wiki/index.php/Open_ReVolt Good news: There seems to be an Open Source code base for using the Atmega in a variety of controller types. Wiki advertises both DC and AC versions. Controller.jpg Didn't look through it carefully. Wi...
by jag
Jan 22 2011 3:17pm
Forum: E-Bike Reviews & Testing
Topic: Cannondale Jekyll Full Suspension with BMC build and review
Replies: 13
Views: 4166

Re: Cannondale Jekyll Full Suspension with BMC build and rev

Winter riding update So how does the equipment hold up? Snow, salt and low temps has been harsh on the 9sp chain and freewheel. Freewheel is now pretty gummed up. Will try to thaw inside and get some lightweight oil into it. Rear shock is air and seals drop pressure from 200 to 100psi in a week or ...
by jag
Jan 21 2011 10:52pm
Forum: Battery Technology
Topic: Single Cell chargers Lipo (& Lifepo4 in one?)
Replies: 14
Views: 1518

Re: Single Cell chargers Lipo (& Lifepo4 in one?)

To change the voltage of a switched PSU it is better to look inside for the resistors that control the voltage setpoint. I've bought lots of 2A switched small "wall-wart" supplies for $1-$2. It's been possible to change two resistors to set the voltage to charge LiFePO4. Some notes: The supplies I t...
by jag
Jan 18 2011 10:10pm
Forum: E-Bike Technical
Topic: Stock 9C Kit Enhancements
Replies: 8
Views: 1031

Re: Stock 9C Kit Enhancements

Top speed about 27 mph Max current CA indicates is 20A, generally 15A is the max that I see Loses speed significantly on mild grade (maybe 5-6%), need to pedal to keep it from stalling Like you suggested, first check that the CA is calibrated right. If the controller is really 35A you should see at...
by jag
Jan 17 2011 11:33pm
Forum: E-Bike General Discussion
Topic: Visiting Hong Kong...
Replies: 6
Views: 712

Re: Visiting Hong Kong...

The peak is a nice visit. Staneley market is interesting, but watch out for fake stuff, like the goretex jacket I bought that was not seam taped, and who knows if it's gore tex at all. Of the islands: For a quiet time on a small island try Lamar island, a short ferry ride away. For a longer outdoor ...
by jag
Jan 14 2011 11:18pm
Forum: E-Bike General Discussion
Topic: Rear hub motor options
Replies: 10
Views: 957

Re: Rear hub motor options

I'd suggest stick with the 9C you have, and put your money in batteries. The BMC/MAC/eZee big geared hubs do significantly better up hills, or when pulling a trailer, but for a flat commute the 9C is good enough. Since you will go LiPo the wind of the 9C matters less. For the slow wind just series m...
by jag
Jan 14 2011 11:13pm
Forum: E-Bike General Discussion
Topic: Germany needs help!!!
Replies: 2
Views: 341

Re: Germany needs help!!!

Those two motors are both brushed DC motors. Old technology. Also, they have no internal gears, so they would be best applied with a 5:1 or 6:1 or thereabouts reduction gearing using a separate chain to the rear wheel, e.g a 10 tooth sprocket on motor and 50-60 tooth on rear wheel. Such a build can ...
by jag
Jan 14 2011 10:44pm
Forum: E-Vehicles General Discussion
Topic: Governments will tax electricity for vehicles
Replies: 19
Views: 1840

Re: Governments will tax electricity for vehicles

I'll gladly pay some kind of annual registration for an electric moped or very light EV as long as it's somehow relative to the weight of my EVs compared to cars and trucks. I consider those kinds of fees to be road use taxes, and those revenues should go only to building, maintaining, and policing...
by jag
Jan 14 2011 10:09pm
Forum: General Discussion
Topic: OR Democrat proposes banning child bike passengers
Replies: 11
Views: 1072

Re: OR Democrat proposes banning child bike passengers

John in CR wrote:I propose that children be banned as passengers in automobiles. Wouldn't that save more lives?
Yup. Burt Rutan, of space ship one fame, makes that statistic obviously clear in his talks. Getting killed in a car crash is one of the biggest causes of death for kids.
by jag
Jan 13 2011 10:35pm
Forum: E-Bike Non-hub Motor Drives
Topic: Can a custom extruded rim w/belt groove be made?
Replies: 6
Views: 1809

Re: Can a custom extruded rim w/belt groove be made?

This is a question for those of you who know how to deal with manufacturers. Would it be possible to order an extruded rim that had a belt groove off to one side? Such a rim seems like it would be a potentially cheap and effective way to get a big reduction to a motor. Another option would be to bo...
by jag
Jan 08 2011 10:32pm
Forum: E-Vehicles General Discussion
Topic: Aluminum VS steel frame construction, a discussion
Replies: 58
Views: 7706

Re: Aluminum VS steel frame construction, a discussion

First thanks to Jeremy and others for the detailed technical info. Good to know when designing or comparing designs on paper. Now for some less scientific information, yet perhaps of practical interest. I just tested four frames for lateral stiffness. I just gave them a push in the crank area by han...