Search found 11612 matches

by fechter
Jan 21, 2018 8:09 pm
Forum: E-Bike General Discussion
Topic: Challenge with brakes
Replies: 13
Views: 206

Re: Challenge with brakes

If you wait long enough the images might appear.

This is what I was looking at.
Bike Frame 1.JPG
Bike Frame 1.JPG (161.84 KiB) Viewed 18 times
by fechter
Jan 21, 2018 8:02 pm
Forum: Battery Technology
Topic: Solder longevity on nickel
Replies: 8
Views: 105

Re: Solder longevity on nickel

Are you sure you have nickel and not stainless steel? Nickel flows nicely with just a little flux. You can use rosin (non-acid) flux.
by fechter
Jan 21, 2018 1:37 pm
Forum: E-Bike General Discussion
Topic: Challenge with brakes
Replies: 13
Views: 206

Re: Challenge with brakes

The seat stays look like they have mounts for rim brakes.
by fechter
Jan 21, 2018 1:33 am
Forum: Vendor Relations Corner
Topic: Voltaplex
Replies: 1
Views: 35

Re: Voltaplex

Never heard of them. Their website says:
Our manufacturing centers are in Dongguan, Shenzhen, and Xiamen, PRC. Our mailing and marketing office is located in Hong Kong.
by fechter
Jan 21, 2018 1:21 am
Forum: E-Bike Technical
Topic: Anyone know the name of this connector and how to disconnect it?
Replies: 4
Views: 83

Re: Anyone know the name of this connector and how to disconnect it?

I bet they glued it with hot melt glue. If you press the release tab, it should come apart easily. You could try heating with a hair dryer to soften the glue. Rubbing alcohol also helps release hot melt glue (use cold). If all else fails, just cut the wires and get a new connector.
by fechter
Jan 20, 2018 5:39 pm
Forum: Motor Technology
Topic: E-Bike Problems
Replies: 2
Views: 37

Re: E-Bike Problems

Could possibly be the brake switches. You could try just unplugging them and test.

Also make sure the battery is charged. If the battery voltage is too low, it cuts off the power.
by fechter
Jan 20, 2018 5:36 pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 664
Views: 51441

Re: Active pre-charge/inrush control

For turn off, you could borrow part of the circuit below (done by one of our members long ago). Just substitute your Schmitt trigger for the input. This circuit provides a fast turn off even with a slow input. The gate driver chip I found can reduce the parts count quite a bit, but maybe not the cos...
by fechter
Jan 20, 2018 4:20 pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 664
Views: 51441

Re: Active pre-charge/inrush control

I think it will work, but it needs to be tested. My spot welder uses the FETs to switch against essentially a dead short, with current over 2000A and they work fine.
by fechter
Jan 20, 2018 4:18 pm
Forum: E-Bike General Discussion
Topic: Marin County, San Francisco Bay Area?
Replies: 19
Views: 234

Re: Marin County, San Francisco Bay Area?

If you live in Marin County, at least one rider is planning to attend the next meeting on this subject. https://electricbikereview.com/forum/threads/voice-your-support-for-ebikes-on-trails-in-marin-county.15866/ https://www.meetup.com/ebiketreks/events/246886216/?_cookie-check=lj6j73uK6dh-Qypv That...
by fechter
Jan 20, 2018 1:54 pm
Forum: Battery Technology
Topic: Solder longevity on nickel
Replies: 8
Views: 105

Re: Solder longevity on nickel

Generally, solder works great on nickel. Good long term.

You may need to use some flux and cleaning the nickel first helps. The mechanical strength of solder is less than nickel, so it will peel if you pull hard enough.
by fechter
Jan 20, 2018 1:24 pm
Forum: General Discussion
Topic: Reid Welch Returns (was Re: E.S. Quotable Quotes !)
Replies: 13
Views: 152

Reid Welch Returns (was Re: E.S. Quotable Quotes !)

Reid_Welch wrote:
Jan 20, 2018 12:21 pm
what goes around comes around
Is that really our Reid Welch? Back from another dimension?
by fechter
Jan 20, 2018 1:00 pm
Forum: E-Bike Photos & Video
Topic: A2b metro gti
Replies: 76
Views: 4799

Re: A2b metro gti

Here is the build thread for my A2B Metro:
https://endless-sphere.com/forums/viewt ... =6&t=50590

I used the stock motor and modified it for an external controller. So much better now.
by fechter
Jan 19, 2018 8:38 pm
Forum: E-Bike Photos & Video
Topic: A2b metro gti
Replies: 76
Views: 4799

Re: A2b metro gti

I have a 14s, 9p pack I put on the back of my A2B. It weighs about 13.5lb. The weight on the rear doesn't really seem to bother the handling much. If I'm just running to the store or a short trip, I use the frame pack, but for longer rides I put the big battery on the rear and have two batteries. 50...
by fechter
Jan 19, 2018 8:30 pm
Forum: Battery Technology
Topic: Chilwee lead-graphene battery
Replies: 19
Views: 249

Re: Chilwee lead-graphene battery

I've never heard of those before. ADVANTAGES * Capacity has been increased 10 - 16%; * Cycle life has been increased 50% more; * Low/High Temperature performance has been improved 30-40%; * Water Loss rate has been decreased 40%; * Large power discharge capability has been increased 15%; * Special c...
by fechter
Jan 19, 2018 8:04 pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 664
Views: 51441

Re: Active pre-charge/inrush control

If you look at the SOA graph for your FETs, you'll probably find this application put them outside of the envelope, but since it's a single event, they seem to survive. The die can absorb some of the heat. The early precharge circuits just used a RC on the gate to slow the turn on, with no feedback ...
by fechter
Jan 19, 2018 7:57 pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: R Martin EVD Moped with HubMonster
Replies: 26
Views: 392

Re: R Martin EVD Moped with HubMonster

6.5v on the lead battery isn't a good sign. Time to recycle. A 50Ahr lithium battery will probably give about twice the range as a 50Ahr lead acid battery. Less weight combined with less Peukert effect. Just for reference, here's the dimensions of a Nissan Leaf battery module. These are 2s each, rat...
by fechter
Jan 19, 2018 3:21 pm
Forum: Motor Technology
Topic: Cromotor issue... bad sound and lack of power
Replies: 9
Views: 97

Re: Cromotor issue... bad sound and lack of power

It sounds like all the magnets broke loose. They can spin around on the inside of the hub, only held on by magnetism. If the glue gets hot enough, it weakens significantly. Ferrofluid could possibly be a factor, but most glues used to stick magnets to the motor should be compatible with it. It would...
by fechter
Jan 19, 2018 3:06 pm
Forum: E-Bike General Discussion
Topic: Marin County, San Francisco Bay Area?
Replies: 19
Views: 234

Re: Marin County, San Francisco Bay Area?

They don't like wind power either. Birds get killed by hitting the blades.

I guess they think it's OK when the birds get killed by global warming instead.
by fechter
Jan 19, 2018 3:04 pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 664
Views: 51441

Re: Active pre-charge/inrush control

That looks a lot like one of our earliest versions. Lots of blown FETs unless you make it super slow.
by fechter
Jan 19, 2018 9:38 am
Forum: E-Scooter and Motorcycle General Discussion
Topic: R Martin EVD Moped with HubMonster
Replies: 26
Views: 392

Re: R Martin EVD Moped with HubMonster

You might be able to fit some Nissan Leaf batteries in there. Even if you fill the entire battery compartment with lithium batteries, it will weigh about 1/3 of the lead batteries.
by fechter
Jan 19, 2018 9:16 am
Forum: General Discussion
Topic: la Nina rears her ugly head
Replies: 621
Views: 21022

Re: la Nina rears her ugly head

0.1" here yesterday. Just sort of drizzled all day.
by fechter
Jan 19, 2018 9:08 am
Forum: E-Bike Technical
Topic: What could be wrong with my bike?
Replies: 18
Views: 379

Re: What could be wrong with my bike?

When I had the connector on the black and blue it would switch between 0.02v and 4.97v as I turned the wheel. The exact same values were there for the black and green. The black and yellow combination went from 0.02v to 4.89v. That sounds pretty normal. I don't think that much difference is a probl...
by fechter
Jan 18, 2018 10:28 pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 664
Views: 51441

Re: Active pre-charge/inrush control

Food for thought; another possible approach to this problem is to switch the main FETs on hard instead of slowly ramping things up. You'd still need a time delay in the case of not using a switch. Based on what I've seen with the spot welder circuits, I think the FETs would be OK with a fast turn-on...
by fechter
Jan 18, 2018 5:11 pm
Forum: E-Bike General Discussion
Topic: Marin County, San Francisco Bay Area?
Replies: 19
Views: 234

Re: Marin County, San Francisco Bay Area?

After a little more research, it seems it was the hard-core tree huggers that were against the electric bikes, not the MTB gods. The original article states: County supervisors Jan. 9 also approved, on first reading, an ordinance that would amend Open Space District regulations. Several environmenta...
by fechter
Jan 18, 2018 3:08 pm
Forum: E-Bike General Discussion
Topic: looking for tire recommendations for 1200 watt bike
Replies: 7
Views: 182

Re: looking for tire recommendations for 1200 watt bike

Your tire failure sounds like maybe the tire was quite old, possibly sat around on a shelf for too many years. Many people have given favorable reports on the Big Apple tires. If you want really tough tires and are willing to trade off for extra weight and a lot more rolling resistance, you could go...