Search found 383 matches

by Buk___
Jan 23, 2018 7:51 am
Forum: Motor Technology
Topic: Mid drive vs Hub Motor for 10000 watt project
Replies: 69
Views: 1402

Re: Mid drive vs Hub Motor for 10000 watt project

x.l.r.8 wrote:
Jan 23, 2018 6:23 am
That controller looks suspiciously like the daymak em1. i would go for a recognized controller rather than one of these. That just my personal opinion though
What is the betting that Daymak buy their controllers from YuYang King?
by Buk___
Jan 22, 2018 3:39 am
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 101
Views: 1370

Re: Potential Catastrophic Frame Failer Averted ….sort of.

I can’t see why. I mean, Ti can be heated high temp without damage, turning any resin leftovers to ashes. It's strength may not be compromised, but it can sure as hell distort. With 13kJ/g of energy given off -- ignoring the heat input to ignite it -- unless you used an oven a raised the whole thin...
by Buk___
Jan 22, 2018 3:15 am
Forum: E-Bike Technical
Topic: Specifications
Replies: 15
Views: 333

Re: Cute Q100H Clutch modification

Papa wrote:
Jan 22, 2018 2:52 am
Images are yet another issue - flash doesn't mesh well with shinny objects.
Indeed. You either need a diffuser, or a (off camera) flash you can bounce off the ceiling or similar.
by Buk___
Jan 22, 2018 12:18 am
Forum: E-Bike Photos & Video
Topic: Single-speed track stealth ultralight
Replies: 41
Views: 1698

Re: Single-speed track stealth ultralight

Yes. But the weight is on me, rather than being on the bike. With the battery pack in the seat bag it felt like the bike wanted to tip over more than I intended it to. If the weight is on me I figure my body will compensate better. I know before I was saying that I already had a bunch of weight on ...
by Buk___
Jan 21, 2018 11:38 pm
Forum: E-Bike Photos & Video
Topic: Single-speed track stealth ultralight
Replies: 41
Views: 1698

Re: Single-speed track stealth ultralight

Well. I got my battery shrink-wrapped and into the seat bag, and I hated it. It made the bike feel really top-heavy and running wires cleanly was going to be a pain in the ass. So... I decided I'd deconstruct it and make a backpack battery. Isn't moving the batteries even higher (onto your back) go...
by Buk___
Jan 21, 2018 11:31 pm
Forum: E-Bike Technical
Topic: Specifications
Replies: 15
Views: 333

Re: Cute Q100H Clutch modification

Q100H Sprag Clutch modification - See images 6a and 6b above. I used the original rollers and the original, trimmed-to-length springs. Then I used three each, 0.156" (3.96mm) diameter ball bearings (heisted from a bicycle headset bearing). This mod places a ball bearing between the roller and the s...
by Buk___
Jan 21, 2018 10:03 am
Forum: Motor Technology
Topic: Mid drive vs Hub Motor for 10000 watt project
Replies: 69
Views: 1402

Re: Mid drive vs Hub Motor for 10000 watt project

johnnyz wrote:
Jan 21, 2018 8:52 am
... soldered 10 gauge solid copper wire with a Tesla style connections ...
What gauge/type of wire did you use for your fusible links?
by Buk___
Jan 21, 2018 1:04 am
Forum: E-Bike Technical
Topic: Anyone know the name of this connector and how to disconnect it?
Replies: 4
Views: 102

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

Appbeza wrote:
Jan 20, 2018 11:07 pm
https://imgur.com/a/LS2dC

Tried for like 20 minutes to disconnect it. But failed.
Looks vaguely like this one; but that doesn't help you get it apart.
by Buk___
Jan 20, 2018 7:56 am
Forum: Motor Technology
Topic: Cromotor issue... bad sound and lack of power
Replies: 9
Views: 104

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

@Buk, not sure to be honest, but if you are getting a geared motor so hot that you need ff you are probably going to melt/chew up the nylon cogs, and are probably wildly over amping and overvolting the motor. Or you may have your wiring incorrect. My motor gets too hot to hold my hand on the surfac...
by Buk___
Jan 20, 2018 2:50 am
Forum: Motor Technology
Topic: Cromotor issue... bad sound and lack of power
Replies: 9
Views: 104

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

brumbrum wrote:
Jan 19, 2018 11:49 am
Yeah , i know theres no clutch, just has sensation like clutch slipping.
Sorry for the apparently dumb question.

I have a geared hub with a clutch, and have been wondering whether it would be compatible with ferrofluid.

I saw mention of "clutch slip" and didn't know a cromotor was a DD.
by Buk___
Jan 19, 2018 11:04 am
Forum: Motor Technology
Topic: Cromotor issue... bad sound and lack of power
Replies: 9
Views: 104

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

Here’s the low down Cromotor, all good for past 2 years until now. added ferrofluid And hubsink, took for test ride, ok for 15 minutes doing hard start stops up to 120 amp to help heat motor and check temps. All good and then the sound came along. It happens with any sudden amp increase but not so ...
by Buk___
Jan 19, 2018 10:56 am
Forum: E-Bike Technical
Topic: Specifications
Replies: 15
Views: 333

Re: Cute Q100H Autopsy & Modify 2017

What do you want to know? I'd like to know: What the gear ratio is. I've seen numbers ranging from 13.something through 16:1. The dimensions of the planet gears. Tooth counts, PCD and width. Bearing size. (Most of this I could probably derive from an hi res picture.) The diameter and width of the r...
by Buk___
Jan 19, 2018 1:15 am
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 101
Views: 1370

Re: Potential Catastrophic Frame Failer Averted ….sort of.

Chalo wrote:
Jan 19, 2018 12:48 am
And yet at the end of the day (quarter-century, to be accurate), the steel frames usually give up first. Go figure.
Nice anecdote!

Now provide some independent verifiable evidence?
by Buk___
Jan 19, 2018 12:33 am
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 101
Views: 1370

Re: Potential Catastrophic Frame Failer Averted ….sort of.

Even on my road bike, I look for the biggest sets of stairs to drop or climb, and ride over log piles and aggressive downhill trails,... For that reason my roadbike is cromoly, and the frame has not yet broken... After some more thinking and verifying. Whilst those drops and jumps are almost certai...
by Buk___
Jan 18, 2018 10:50 pm
Forum: E-Bike Technical
Topic: Specifications
Replies: 15
Views: 333

Re: Cute Q100H Autopsy & Modify 2017

Good question - I haven't really looked. I have. I believe I read every thread/post that mentions Q128H on this site. And damn there are a lot of them; even if you exclude those where the mention is in someone sig. But the picture that emerges is very confused, because there seem to have been at le...
by Buk___
Jan 18, 2018 8:53 pm
Forum: E-Bike Technical
Topic: Specifications
Replies: 15
Views: 333

Re: Cute Q100H Autopsy & Modify 2017

Q100H 328 front hub purchased (12/2017). AKM17092301002 / AAD3616A-H / QC-PASS round sticker stating "16 Inches" (white/green) Ratio: 8.139:1 - Gears - / motor 15t / first stage planets 36t / second stage planets 23t / final ring 78t Laminates: 49 stack count - 0.35mm thickness each *** MORE IMAGES...
by Buk___
Jan 18, 2018 8:45 pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 664
Views: 51513

Re: Active pre-charge/inrush control

An RC circuit can be used for the precharge but it will be very slow depending on the values. My simulation shows a 1m (1,000uf) load capacitor. That 10k will take more than 30 seconds to reach 95 of the 100 volts I have. Charging at a constant current through the mosfets gets to full voltage in 0....
by Buk___
Jan 18, 2018 6:21 pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 664
Views: 51513

Re: Active pre-charge/inrush control

In some applications it is desirable to have no switch, just connect and disconnect power without inrush or arcing. This can be done using sequential contact mating as I show in this spice simulation. The output mosfets are off at the right times because M2 turns off the gate voltage during contact...
by Buk___
Jan 18, 2018 5:24 pm
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 101
Views: 1370

Re: Potential Catastrophic Frame Failer Averted ….sort of.

Everyone has a different kind of riding preference. Even on my road bike, I look for the biggest sets of stairs to drop or climb, and ride over log piles and aggressive downhill trails, and it still feels like inadquate training for cyclocross racing. Would you agree that you are an outlier on the ...
by Buk___
Jan 18, 2018 5:00 pm
Forum: E-Bike Non-hub Motor Drives
Topic: My Bafang Ultra Mountain Bike! Frey AM1000
Replies: 287
Views: 12517

Re: My Bafang Ultra Mountain Bike! Frey AM1000

Just received 2 photos of the prototype Frey AM 1000 Fatbike from Ivy Wang. I think it is looking really good, and can't wait to see the production version, and receive pricing and final specifications. I have particularly asked them to manufacture Front And Rear Fenders as a factory option.. I thi...
by Buk___
Jan 18, 2018 4:51 pm
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 101
Views: 1370

Re: Potential Catastrophic Frame Failer Averted ….sort of.

liveforphysics wrote:
Jan 18, 2018 4:50 pm
My bike is 18.5lbs fully assembled with cyclocross tires. I don't know the bare frame weight.
I read bad info. I've corrected my mistake above.
by Buk___
Jan 18, 2018 4:32 pm
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 101
Views: 1370

Re: Potential Catastrophic Frame Failer Averted ….sort of.

It's a 2002 Lemond Zurich using Reynolds 853 (the predecessor of the amazing 953) running a mix of dura-ace components with a cable pull ratio modified modern XTR rear derailleur (for it's auto-chain tensioner function that is awesome for avoiding chain drama on big impacts). The tubes are butted t...
by Buk___
Jan 18, 2018 4:09 pm
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 101
Views: 1370

Re: Potential Catastrophic Frame Failer Averted ….sort of.

Even on my road bike, I look for the biggest sets of stairs to drop or climb, and ride over log piles and aggressive downhill trails, and it still feels like inadquate training for cyclocross racing. For that reason my roadbike is cromoly, and the frame has not yet broken (though I go through wheel...
by Buk___
Jan 18, 2018 2:53 pm
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 101
Views: 1370

Re: Potential Catastrophic Frame Failer Averted ….sort of.

I've personally never felt like pedaling related forces were significant compared to riding impact related forces. Right. Potholes and even little bumps can have much higher instantaneous peaks (even if the durations are short), Still missing the point. You don't generally ride from one pothole to ...
by Buk___
Jan 18, 2018 2:46 pm
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 101
Views: 1370

Re: Potential Catastrophic Frame Failer Averted ….sort of.

[...]well below the 480Mpa fatigue limit of normalised ChroMoly. That's close to the yield stress of normalized 4130, so the fatigue limit would be not much more than half that. Wrong again. Fatigue limit is usually roughly half of the ultimate tensile strength , not the yield strength. Here the wo...