Search found 45 matches

by otas
Jun 26 2018 5:06am
Forum: E-Scooter and Motorcycle General Discussion
Topic: Why Is my scooter struggling battery sag?
Replies: 24
Views: 1524

Re: Why Is my scooter struggling battery sag?

I am in a similar position, I have Erider Model 30 with 5 x 12V 20A led acid batteries not even 2 years old. My range is hardly 12m. On flat I can reach 30mph. Uphill it struggles. From 62V it drops under load to 54V whilst drawing 17A. So I am thinking about hybrid. IC generator 4 stroke and smalle...
by otas
Feb 07 2011 2:29pm
Forum: E-Bike Build Threads / Photos & Video
Topic: Stealth folding bike - UPDATE
Replies: 62
Views: 7900

Re: Stealth folding bike - UPDATE

Thanks for results of your homework Jeremy, yes, the DNP looks like stamped from a cheese, not steel. This one looks like an honest job. I got worked up on the 11gear, which would be 27% improvement, this is only 16%. I have friendly machine CNC shop in CR, they are crazy into racing Moped Stadion, ...
by otas
Feb 07 2011 11:10am
Forum: E-Bike Build Threads / Photos & Video
Topic: Stealth folding bike - UPDATE
Replies: 62
Views: 7900

Re: Stealth folding bike - UPDATE

here u go jeremy 11-32 7spd freewheel http://www.ebike-solutions.de/epages/62204758.sf/de_DE/?ObjectPath=/Shops/62204758/Categories/Schraubkr%C3%A4nze also here http://www.v-fiets.com/shop/Overbrengingen-c-279.html Thanks a lot, that's a great help, just what I was after! Jeremy Jeremy, have you tr...
by otas
Jan 29 2011 9:12am
Forum: E-Bike Technical
Topic: Simple ebike 'fuel gauge'
Replies: 126
Views: 26241

Re: Simple ebike 'fuel gauge'

Hi Magudaman, nice job, shame about the slot. What about drilling individual holes, if no mill is at hand?

otto
by otas
Jan 26 2011 2:13pm
Forum: E-Bike Build Threads / Photos & Video
Topic: Stealth folding bike - UPDATE
Replies: 62
Views: 7900

Re: Stealth folding bike - UPDATE

Today I rode despite the drizzle and 5 deg., just 4 miles, fantastic. Throttle LED gauge still on max. I need windscreen wipers for my goggles. Any suggestions? Max. speed 29mph, avg 17.8mph. My front chainwheel is 52, and I can pedal up to 23-24mph, but I have to pedal like mad. I have lost the cha...
by otas
Jan 25 2011 6:16am
Forum: E-Bike Technical
Topic: Simple ebike 'fuel gauge'
Replies: 126
Views: 26241

Re: Simple ebike 'fuel gauge'

What about using a little picaxe to drive the leds on the throttle ?. That way it could be made precise to drive all 3 (?) leds. Gwhy, there is perhaps a little misunderstanding. The modified throttle indicator works fine with all 4 LEDs working as they should in the max-min-empty display. It has g...
by otas
Jan 24 2011 1:19pm
Forum: E-Bike Technical
Topic: Simple ebike 'fuel gauge'
Replies: 126
Views: 26241

Re: Simple ebike 'fuel gauge'

Exactly, but I wanted to KISS - keep it simple s... LED's will start dropping off after approx 70% remaining power, which I think is acceptable. For me at least... I'm not sure that this will really be the case. I did something similar to lower the trigger voltage of the LEDs on my throttle (I just...
by otas
Jan 24 2011 1:09pm
Forum: E-Bike Technical
Topic: Simple ebike 'fuel gauge'
Replies: 126
Views: 26241

Re: Simple ebike 'fuel gauge'

Cheap and small 5v power supplies : A friend has just loaned me a controller with a cycle analyst plug built in (6 pin connector) which has made me rethink my power options. For PIC and little associated logic circuit supply I use a drop resistor, zener BZX-C5V1 and ceramic 100nF 50V cap. as a filt...
by otas
Jan 23 2011 7:48am
Forum: E-Bike Technical
Topic: Simple ebike 'fuel gauge'
Replies: 126
Views: 26241

Re: Simple ebike 'fuel gauge'

Exactly, but I wanted to KISS - keep it simple s... LED's will start dropping off after approx 70% remaining power, which I think is acceptable. For me at least...
by otas
Jan 22 2011 7:30pm
Forum: E-Bike Technical
Topic: Simple ebike 'fuel gauge'
Replies: 126
Views: 26241

Re: Simple ebike 'fuel gauge'

I am moving my intended project of Jeremy's PIC power indicator with linear LED display further into infinity, but I need now at least the indication of voltage of the battery. The original LED indicator on the twist throttle is in a good position, is for 24V lead battery and cannot do much on my 40...
by otas
Jan 19 2011 4:51am
Forum: E-Bike Build Threads / Photos & Video
Topic: Stealth folding bike - UPDATE
Replies: 62
Views: 7900

Re: Stealth folding bike - UPDATE

Hi Chekola, I rode the bike yesterday, but it was so bitterly cold, 3deg C above, so I gave up after 3 miles. I will wrap up proper and try again.
cheers otto
by otas
Jan 10 2011 7:06pm
Forum: E-Bike Build Threads / Photos & Video
Topic: Stealth folding bike - UPDATE
Replies: 62
Views: 7900

Re: Stealth folding bike - UPDATE

Nice job, Otto, I'm glad you got it running OK. I charge my pack in two halves. I have made up small adapters to connect each pair of 5S packs together, and have shortened the pack leads and configured then so I can just pull out the two paralleled packs as if they were just two 5S packs, isolated ...
by otas
Jan 09 2011 7:29pm
Forum: Battery Technology
Topic: 15S LiPo charger using DC DC converters
Replies: 69
Views: 13072

Re: 15S LiPo charger using DC DC converters

I am reluctant to use connector, as I want to leave it permanently connected. How about a diode in each DC-DC convertor feeding the Lipo batt. with the voltage sense before the diode. The DC-DC convertor output would have to be increased due to the forward voltage drop, and we would have to compensa...
by otas
Jan 09 2011 7:04pm
Forum: Motor Technology
Topic: ICE candidates for hybrid motorcycle
Replies: 70
Views: 7805

Re: ICE candidates for hybrid motorcycle

Jeremy, thanks for your comments. Sorry, I have just read it now, after spending an afternoon actually riding the "stealth ebike". In the excitement I have started a new thread on Hybrid EGO scooter with genset. I did not want to sidetrack this thread, as they are quite diff. approaches. I will take...
by otas
Jan 09 2011 2:13pm
Forum: E-Bike Build Threads / Photos & Video
Topic: Stealth folding bike - UPDATE
Replies: 62
Views: 7900

Re: Stealth folding bike - UPDATE

Thanks Jeremy, I programmed it with 30A and 70A phase current, I rode for 1.5 mile, it was dark and bitterly cold, but bike feels lively and snappy. I could see 25+ mph most of the journey. I think that's enaugh, I have to do something with the brakes. Mosfets and motor are cool as a cucumber. I hav...
by otas
Jan 09 2011 10:24am
Forum: E-Bike Build Threads / Photos & Video
Topic: Stealth folding bike - UPDATE
Replies: 62
Views: 7900

Re: Stealth folding bike - UPDATE

I have finally rode the bike this afternoon, and I have a big grin ear to ear. It was quite an uphill struggle, getting the USB programming cable set-up, getting connectors (thanks to Jeremy's supplier links and his initial controller parameters). Keywins connector interpratation was very loose, so ...
by otas
Jan 08 2011 9:38pm
Forum: Battery Technology
Topic: 15S LiPo charger using DC DC converters
Replies: 69
Views: 13072

Re: DC DC converters for charging LiPo

I'd be wary of fitting a charging system like this on to a bike, for two reasons. Firstly, the converters will draw a small current from the cells all the time they are connected and not powered, as they have a voltage sense circuit connected to the output. Secondly, they get pretty hot when delive...
by otas
Jan 05 2011 9:41pm
Forum: Motor Technology
Topic: ICE candidates for hybrid motorcycle
Replies: 70
Views: 7805

Re: ICE candidates for hybrid motorcycle

Just thought I'd pop this link in here (I found it whilst looking for something else), as it looks like a neat idea for a generator for small series hybrid arrangement: http://www.torcman.de/faszination/praxis/jochen/honda-gx35_430-30.htm One of these mounted on a rear rack would give you a pretty ...
by otas
Jan 03 2011 3:57pm
Forum: E-Bike Build Threads / Photos & Video
Topic: John in CR's monocoque composite frame build log
Replies: 86
Views: 10854

Re: John in CR's monocoque composite frame build log

Ouch, that explains he did not react to my czech gobbledy gook!
Thanks for the explanation Jeremy.
You see I am new to this community and just about finding my way around and the abbreviations and assumptions can be misleading.
otto
by otas
Jan 03 2011 3:52pm
Forum: E-Bike Build Threads / Photos & Video
Topic: Stealth folding bike - UPDATE
Replies: 62
Views: 7900

Re: Stealth folding bike - UPDATE

Jeremy, thank you very much for the parameters, is it very much the standard Keywins setting? I will try it tomorrow. Shame the snow has gone, so I cannot share the fun with you!
regards
otto
by otas
Jan 03 2011 11:38am
Forum: E-Bike Build Threads / Photos & Video
Topic: Stealth folding bike - UPDATE
Replies: 62
Views: 7900

Re: Stealth folding bike - UPDATE

Jeremy, I am in a great expectation for tomorrow, I shall receive my Zippy's 5000mah 4x 5S1P batteries, so hopefully I will be able to try out the bike. Would you be so kind and copy me on your setting of Keywins' controller, so that I see what you are running, please?
Thank you very much.
otto
by otas
Jan 03 2011 4:45am
Forum: E-Bike Build Threads / Photos & Video
Topic: John in CR's monocoque composite frame build log
Replies: 86
Views: 10854

Re: John in CR's monocoque composite frame build log

John,
preji vse nejlepsi do Noveho Roku 2011 a hodne stesti v novem projektu.
Kde v CR se vyskytujes? Ja jsem obcas v JC na Taborskem letisti. Bylo by prijemne se treba setkat.
ahoj ota
by otas
Jan 01 2011 6:55am
Forum: E-Bike Build Threads / Photos & Video
Topic: Stealth folding bike - UPDATE
Replies: 62
Views: 7900

Re: Stealth folding bike - UPDATE

Evoforce, as I am in UK, I cannot comment on legislation, but I am sure the VW giant will come up with something, if they think there is enough money in it. Looking at your e-bikes with a solar charging - do you have solar panels on or off the bike? What output? At this stage I am at the first step,...
by otas
Dec 31 2010 7:33am
Forum: Motor Technology
Topic: Simple BLDC controller
Replies: 407
Views: 66155

Re: Simple BLDC controller

Nice job, Jeremy! What software do you use for layout? Thanks, Alan. You probably need to be sitting down and promise not to chuckle, but the layout is done by hand, using an old version of Autocad (Autocad 2000) that I'm just used to working with for other mechanical stuff. It didn't seem worth go...
by otas
Dec 31 2010 5:16am
Forum: E-Bike Build Threads / Photos & Video
Topic: Stealth folding bike - UPDATE
Replies: 62
Views: 7900

Re: Stealth folding bike - UPDATE

Wishing you all the best for the New Year, with our Lipo's not going up in a bang and coming down in price.
Here is a VW attempt at stealth e-bike, please note: no wires, no cables, no batteries to be seen...
I am waiting eagerly for a knock-off from china :D