Search found 5757 matches

by Chalo
Jan 20, 2018 3:42 pm
Forum: EV Business World
Topic: Tesla Model 3
Replies: 226
Views: 12924

Re: Tesla Model 3

You do realize that Tesla has never made a profit and are $4.5 billion dollars in debt? I love their cars, but how do you stay in business if you never make a profit? https://www.forbes.com/sites/chuckjones/2018/01/05/teslas-debt-rating-could-go-farther-into-the-ditch/ I remember lots of people, in...
by Chalo
Jan 20, 2018 3:24 pm
Forum: E-Bike General Discussion
Topic: Sortimo electric cargo trikes
Replies: 20
Views: 215

Re: Sortimo electric cargo trikes

gogo wrote:
Jan 20, 2018 10:00 am
Delta means two wheels in the rear. These Delta trikes don't tip over: http://www.vigillante.com/vigillante2.htm
That looks like a real cargo champ there. Probably also a honey in city traffic, with great visibility and maneuverability in tight quarters.
by Chalo
Jan 19, 2018 8:35 pm
Forum: E-Bike General Discussion
Topic: Sortimo electric cargo trikes
Replies: 20
Views: 215

Re: Sortimo electric cargo trikes

Cars don't use three wheels to go fast, either. And three-wheeled cars, like three-wheeled "bikes", are known for overturning easily. I don't know what your beef is; this is just a matter of simple fact. The only way to keep from tumbling a trike when things get fast and festive is to put the center...
by Chalo
Jan 19, 2018 6:07 pm
Forum: E-Bike General Discussion
Topic: Upgrading discs to 203 mm - worth it?
Replies: 25
Views: 1513

Re: Upgrading discs to 203 mm - worth it?

Unless you overheat your brakes, I think you'll get better feel from smaller rotors. My big rotor brakes haven't been usefully stronger than other brakes, but they have a more abrupt onset that's a little bothersome. Scour and clean your rotors with brake cleaner, and replace the pads with new semi-...
by Chalo
Jan 19, 2018 5:56 pm
Forum: E-Bike General Discussion
Topic: Sortimo electric cargo trikes
Replies: 20
Views: 215

Re: Sortimo electric cargo trikes

Like for like, the trike will put you on your head sooner, at a lower speed, than any two-wheeler. A dime-store-5mph granny trike perhaps,.. But otherwise.. verifiable nonsense. The trikes I work to design and build are the best in the business. They start at about $6k including passenger carriage....
by Chalo
Jan 19, 2018 4:29 pm
Forum: E-Bike General Discussion
Topic: Sortimo electric cargo trikes
Replies: 20
Views: 215

Re: Sortimo electric cargo trikes

Are you implying that non-tilting, utility trikes are slow and unsafe? I think he's not implying it, but saying it. And it's true. Like for like, the trike will put you on your head sooner, at a lower speed, than any two-wheeler. I've been working with one of my friends to design an e-pedicab that ...
by Chalo
Jan 19, 2018 4:20 pm
Forum: E-Bike General Discussion
Topic: Sortimo electric cargo trikes
Replies: 20
Views: 215

Re: Sortimo electric cargo trikes

...something that you could do cheaper, lighter, and simpler with two wheels. Perhaps, but a few possible points that I considered while pondering options on my BarkFiet ideas: [...] In addition to everything you said, there's also the ability to put cargo in between the front wheels. So you can ha...
by Chalo
Jan 19, 2018 12:48 am
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 92
Views: 1207

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

And yet at the end of the day (quarter-century, to be accurate), the steel frames usually give up first. Go figure.
by Chalo
Jan 18, 2018 11:49 pm
Forum: E-Bike General Discussion
Topic: Sortimo electric cargo trikes
Replies: 20
Views: 215

Re: Sortimo electric cargo trikes

Like most leaning trikes, it's an expensive, heavy, and complicated way to do something that you could do cheaper, lighter, and simpler with two wheels.
by Chalo
Jan 18, 2018 12:06 pm
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 92
Views: 1207

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

Buk___ wrote:
Jan 18, 2018 3:16 am
[...]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.
by Chalo
Jan 18, 2018 11:54 am
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 92
Views: 1207

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), and hard braking winds up a frame much more than hard pedaling. Make t...
by Chalo
Jan 18, 2018 2:19 am
Forum: E-Bike Non-hub Motor Drives
Topic: Project Dauntless - My Tanget build
Replies: 30
Views: 881

Re: Project Dauntless - My Tanget build

Previous needle roller clutch freehubs (Shimano Silent Clutch hubs and Winners hubs) were regarded as less robust and reliable (with pedal power only) than ratchet freehubs.
by Chalo
Jan 18, 2018 2:12 am
Forum: E-Bike Technical
Topic: Repair to bent rim. Advice and help pls
Replies: 18
Views: 242

Re: Repair to bent rim. Advice and help pls

Chukker is a good rim. At least it was when they bought it. This all comes across as very unfortunate.
by Chalo
Jan 18, 2018 1:22 am
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 92
Views: 1207

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

So you are saying that no steel bicycle frames are built to withstand 250MPa stresses? Do you mean built to withstand foreseeable working stresses while remaining under 250MPa throughout? Remember all steels aren't equal in strength, and their fatigue limits are a function of their yield stresses. ...
by Chalo
Jan 17, 2018 9:00 pm
Forum: E-Bike Technical
Topic: Repair to bent rim. Advice and help pls
Replies: 18
Views: 242

Re: Repair to bent rim. Advice and help pls

Yikes, that's really bad. I have built some wheels on rims that bad. I unlaced them, sent them back and started over. Can you share with us what kind of rim they used? The rim is not necessarily the problem, but... it probably is. It would take a truly exceptional amount of incompetence to get a res...
by Chalo
Jan 17, 2018 8:51 pm
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 92
Views: 1207

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

Every time I mention "Al has no fatigue limit", you say: "All structural metals work harden; all of them fatigue." which is a fundamental mis-statement of the facts. You know that steel work hardens. It's why we cold forge things. And we all know that steel fatigues because we see bikes and other o...
by Chalo
Jan 17, 2018 5:57 pm
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 92
Views: 1207

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

It's like you have learned an engineering concept, but failed to understand its implications or importance in real world engineering. Oh Chalo. I greatly respect your advice about bikes; but please don't think your 10 years as a bike mechanic, and un-cited, anecdotal witticisms make you qualified. ...
by Chalo
Jan 17, 2018 2:51 pm
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 92
Views: 1207

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

Don't get hung up on material. One important structural limitation of aluminium alloys is their fatigue strength. Unlike steels, aluminium alloys have no well-defined fatigue limit, meaning that fatigue failure eventually occurs, under even very small cyclic loadings. Engineers must assess applicat...
by Chalo
Jan 16, 2018 8:12 pm
Forum: E-Bike Non-hub Motor Drives
Topic: New "TSDZ2 Torque Sensor Central Motor"
Replies: 1400
Views: 100454

Re: New "TSDZ2 Torque Sensor Central Motor"

I'm especially curious about the CSK one-way clutch failures. My impression is that the CSK clutch only engages to transmit pedal power, and does not have to transmit motor power. Is this correct? I have been planning to try one of these TSDZ2 units, but I have to be able to pedal strongly without b...
by Chalo
Jan 16, 2018 8:03 pm
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 92
Views: 1207

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

e-beach wrote:
Jan 16, 2018 7:45 pm
So today, I was looking through my local Craigslist and their is mostly junk for sale in the price range I was looking to pay, $150ish because that is probably the cost of getting it welded around here.
http://www.nashbar.com/bikes/Product2_1 ... 0003472_-1
by Chalo
Jan 16, 2018 7:37 pm
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 92
Views: 1207

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

Do you regularly exert 1300N forces to your pedals, whilst cranking the bike over at 7.5 deg to the direction of the force? I don't. I stand up to climb, yes. In my case, that's over 1500N if I'm not pulling on the bars to increase pedal force further. And when I'm standing to climb, I rock the bik...
by Chalo
Jan 16, 2018 5:27 pm
Forum: E-Bike General Discussion
Topic: The winner is . Not what you think
Replies: 21
Views: 512

Re: The winner is . Not what you think

And with time those cars will get smaller, lighter and more efficient (following the same trend they are now.) I don't see such a trend. I know that in 1980, you could buy a car that weighed under a ton, carried four adults, and got 50 mpg. Today, the same car has put on something like 75% more wei...
by Chalo
Jan 16, 2018 1:38 pm
Forum: E-Bike General Discussion
Topic: Marin County, San Francisco Bay Area?
Replies: 19
Views: 226

Re: Marin County, San Francisco Bay Area?

Thank the unregistered-motorcycles-with-pedals dicks whenever e-bikes are banished from public infrastructure. I don't think that's the problem here. I've ridden extensively on the open space trails over the last year and I think I've only seen maybe two other ebikes, and they were Bosch drives. Th...
by Chalo
Jan 16, 2018 1:28 pm
Forum: E-Bike General Discussion
Topic: Potential Catastrophic Frame Failer Averted ….sort of.
Replies: 92
Views: 1207

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

All structural metals work harden; all of them fatigue. One difference that steel has compared to aluminum, is that after repeated loads, aluminum will fatigue. Steel has an indefinite fatigue life, which means it has enough strength to withstand repeated load cycles, and hence, it lasts longer, or...
by Chalo
Jan 16, 2018 3:14 am
Forum: E-Bike General Discussion
Topic: The winner is . Not what you think
Replies: 21
Views: 512

Re: The winner is . Not what you think

It always amazes me when I think to myself that this problem didn't even exist a short 120 years ago, travel by horse and buggy worked pretty good didn't it? When bicycles arose, there was much outrage because they went too fast. I'm sure there were a few hooligans and jackasses who made that impre...