Search found 14887 matches

by fechter
May 06 2021 2:04pm
Forum: EScooters/EMotorcycles
Topic: Fechter's Sur-ron Modifications
Replies: 18
Views: 8467

Re: Fechter's Sur-ron Modifications

Im waiting on mine...I have a question about the extra Battery you made..is it the same Ah?...I will be making another 60 volt 30 ah pack run in parallel, to get a little extra range. It's pretty close. 29.4Ahr based on datasheet for the cells. Actual capacity is probably less since the cells are a...
by fechter
May 06 2021 8:43am
Forum: EScooters/EMotorcycles
Topic: Sur-Ron - New Mid drive Bike
Replies: 5474
Views: 627474

Re: Sur-Ron - New Mid drive Bike

I think you really want all the FETs to be the same and from the same batch so they are well matched.

I like the reinforcement on the terminals. I've seen a couple controllers fail when one of those cracked at the base. It won't hurt to put some epoxy around them when you get everything done.
by fechter
May 04 2021 11:57pm
Forum: E-Vehicles General Discussion
Topic: C Cab Hot Rod Power Advice
Replies: 468
Views: 30919

Re: C Cab Hot Rod Power Advice

It's getting closer. I can't wait for the first road test.
by fechter
May 04 2021 9:53am
Forum: EBike Non-hub Motor Drives
Topic: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue
Replies: 167
Views: 43080

Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

I'm a long time motorcycle rider and rode my BBSHD for over a year with the PAS disabled. Throttle only. It was very natural to me and even after fixing the PAS, I still go with throttle quite often for more precise control. Interestingly, I was recently stopped by a park ranger who asked me if my b...
by fechter
May 04 2021 8:12am
Forum: EBike Non-hub Motor Drives
Topic: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue
Replies: 167
Views: 43080

Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

The newer units appear to be shipped with the "fixed" firmware so it sounds like you got lucky and have the good firmware version. One trick I learned was if you want to cut the power instantly while using the PAS, just pedal backward. Otherwise the motor keeps going for a split second whi...
by fechter
May 03 2021 8:47am
Forum: EBike Build Threads
Topic: A2B Metro (Gen 1) Restoration and Upgrade
Replies: 90
Views: 3437

Re: A2B Metro (Gen 1) Restoration and Upgrade

Thanks for the link. I like the size of those. I think the voltage rating isn't going to be a problem. Close enough.
by fechter
May 03 2021 8:45am
Forum: Motor Technology
Topic: DIY Toroidal Axial Flux PM
Replies: 79
Views: 2048

Re: DIY Toroidal Axial Flux PM

On the Lynch motor, I think they used some kind of ferrite, like the SMC stuff. I was thinking more like lamination strips harvested from an old transformer core. It would be interesting to see how it models. If the iron pieces are too thin, I think they would be prone to saturating, but this is a s...
by fechter
May 02 2021 11:53pm
Forum: EBike Build Threads
Topic: A2B Metro (Gen 1) Restoration and Upgrade
Replies: 90
Views: 3437

Re: A2B Metro (Gen 1) Restoration and Upgrade

where did you get those breakers?
by fechter
May 02 2021 11:05am
Forum: EScooters/EMotorcycles
Topic: Sur-Ron - New Mid drive Bike
Replies: 5474
Views: 627474

Re: Sur-Ron - New Mid drive Bike

stepus wrote:
May 02 2021 5:16am
So if i wanted to 10kW of power its aprox 160Amps battery, and with unchanged ratio battery/phase amps i will get 900 phase amps - quite huge current - probbably i will not go that high...
It works fine at 180 battery amps. You won't actually get 900 phase amps.
by fechter
May 01 2021 11:56am
Forum: Motor Technology
Topic: DIY Toroidal Axial Flux PM
Replies: 79
Views: 2048

Re: DIY Toroidal Axial Flux PM

More winding turns will definitely help. Here's another crazy idea: If you put little strips of iron lamination in the spaces between windings, it will greatly increase the torque/amp. While the iron adds weight, the increased torque will offset it and you may get a better overall power/weight ratio...
by fechter
Apr 29 2021 10:06pm
Forum: Forum Rules and Features
Topic: Big update to the biker bar & order of the forums
Replies: 54
Views: 1521

Re: Big update to the biker bar & order of the forums

Angry Bob is the reincarnated Nelson37, who was banned from the forum.
by fechter
Apr 28 2021 10:44pm
Forum: EScooters/EMotorcycles
Topic: Sur-Ron - New Mid drive Bike
Replies: 5474
Views: 627474

Re: Sur-Ron - New Mid drive Bike

Very interesting. Thanks for posting.

Looks like they got cheap and didn't populate all the power stage FETs.
I've never been able to find a datasheet for those FETs either. No idea what their ratings are.

Your mezzanine connectors look not so good now. Those will need to be replaced.
by fechter
Apr 27 2021 10:07pm
Forum: EScooters/EMotorcycles
Topic: Sur-Ron - New Mid drive Bike
Replies: 5474
Views: 627474

Re: Sur-Ron - New Mid drive Bike

Right hand thread. You can find lug nuts for car wheels in that size.
by fechter
Apr 27 2021 2:11pm
Forum: EBike Non-hub Motor Drives
Topic: Best grease for CYCLONE gearbox.
Replies: 21
Views: 1255

Re: Best grease for CYCLONE gearbox.

Another thing to consider is chainsaw bar and chain lube. I have a Bafang Ultra that melted its plastic gear and I installed a metal one. Not having any suitable grease, I tried the chain bar oil. This oil resembles motor oil, but has additives that make it stick to the metal and not fling off at sp...
by fechter
Apr 26 2021 10:04am
Forum: EBike Build Threads
Topic: A2B Metro (Gen 1) Restoration and Upgrade
Replies: 90
Views: 3437

Re: A2B Metro (Gen 1) Restoration and Upgrade

I'd suggest a separate fuse for the dc-dc. Once you get up to around 72v, you can start using power bricks made for AC line voltage. They are not as compact though.
by fechter
Apr 26 2021 9:55am
Forum: General Discussion
Topic: la Nina rears her ugly head
Replies: 2077
Views: 146027

Re: la Nina rears her ugly head

They were predicting .25-.5" of rain yesterday. It fizzled and I got barely a trace. Still at 10.5" for the season.
by fechter
Apr 25 2021 11:40am
Forum: EBike Build Threads
Topic: A2B Metro (Gen 1) Restoration and Upgrade
Replies: 90
Views: 3437

Re: A2B Metro (Gen 1) Restoration and Upgrade

Good thing you had breakers that worked. Otherwise it would have been a fire.

Can you post a picture of the bad dc-dc? I want to make sure I don't buy one like it.
by fechter
Apr 25 2021 11:38am
Forum: EScooters/EMotorcycles
Topic: Sur-Ron - New Mid drive Bike
Replies: 5474
Views: 627474

Re: Sur-Ron - New Mid drive Bike

The terminal posts are not so easy to solder back. It takes a lot of heat. More heat than my biggest two soldering irons at the same time. The only way I know of to remove the potting is to heat it to around 80-100C where it becomes rubbery, then dig it out with a small screwdriver. It is easy to da...
by fechter
Apr 23 2021 2:46pm
Forum: Motor Technology
Topic: DIY Toroidal Axial Flux PM
Replies: 79
Views: 2048

Re: DIY Toroidal Axial Flux PM

A slight twist in the wires isn't going to increase the resistance too much, but I had real concerns about the one below:
Twisted wires.jpeg
Twisted wires.jpeg (58.27 KiB) Viewed 194 times
The wire length might be 2x longer than untwisted and I have no idea what the twisting would do to the shape of the magnetic field.
by fechter
Apr 23 2021 8:49am
Forum: EScooters/EMotorcycles
Topic: Sur-Ron - New Mid drive Bike
Replies: 5474
Views: 627474

Re: Sur-Ron - New Mid drive Bike

Nice looking batteries! The stock circuit breaker is rated for 100A, but will easily handle a short burst of 200A without tripping. I've been expecting mine to trip but so far it never has. The bike just speeds up so fast the current can't stay that high for very long. Maybe with field weakening it ...
by fechter
Apr 23 2021 8:40am
Forum: Motor Technology
Topic: DIY Toroidal Axial Flux PM
Replies: 79
Views: 2048

Re: DIY Toroidal Axial Flux PM

I think for a Halbach array to work well, the magnets need to be touching each other with no gap. This will be challenging in an axial design. Also, looking at the windings, it seems like twisting them will make each strand longer than they would be if they weren't twisted. If the strands weren't in...
by fechter
Apr 21 2021 2:02pm
Forum: General Discussion
Topic: la Nina rears her ugly head
Replies: 2077
Views: 146027

Re: la Nina rears her ugly head

There's a chance for some rain this weekend here. I'll believe it when I see it.
by fechter
Apr 21 2021 8:02am
Forum: EScooters/EMotorcycles
Topic: Sur-Ron - New Mid drive Bike
Replies: 5474
Views: 627474

Re: Sur-Ron - New Mid drive Bike

Even if there was a circuit breaker of fuse, it may have still blown up the same way. One a part shorts, the breaker can't trip fast enough. It may have prevented things from burning after the explosion though. It looks like the FETs blew, but it would be nice to know for sure what exactly failed. F...
by fechter
Apr 20 2021 10:22pm
Forum: EScooters/EMotorcycles
Topic: Sur-Ron - New Mid drive Bike
Replies: 5474
Views: 627474

Re: Sur-Ron - New Mid drive Bike

You guys see this? Bet that guy had to change his shorts after that. Probably made a pretty loud bang. At least the battery didn't seem to burn. The main circuit breaker is pretty hard to trip. It has to be overloaded for some time before it heats up enough to trip. That thing blew quickly and the ...
by fechter
Apr 20 2021 10:13pm
Forum: EBike Non-hub Motor Drives
Topic: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue
Replies: 167
Views: 43080

Re: DIY Fix for BBS02/BBSHD Pedal/Throttle Issue

Can you post a picture of how the button is mounted?

Also, some reports indicate the "fixed" version of BBSHD firmware will also work on the BBS02 but I can't confirm.