The e-bike thread. - Page 15 - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Insert BS here A place to discuss anything you want

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 05-20-2012, 07:22 PM   #281
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 36,174
Total Cats: 2,575
Default

Quote:
Originally Posted by Joe Perez View Post

It's kind of funny- I've been working on this thing for a week's worth of weekends, and it hardly looks any different from a standard bicycle.
Time to: HELLAFLUSH IT
Attached Thumbnails
The e-bike thread.-bike02.jpg  
18psi is offline   Reply With Quote
Old 05-20-2012, 07:26 PM   #282
Elite Member
iTrader: (21)
 
Join Date: Jun 2007
Location: Rochester, NY
Posts: 5,684
Total Cats: 555
Default

That is obscene.
rleete is offline   Reply With Quote
Old 05-20-2012, 09:58 PM   #283
Boost Pope
Thread Starter
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,914
Default

Sidebar:

If you disconnect the brake sensor, you can indeed use the rear disc brake as a dyno load in order to calibrate your equipment with the wheel in the air.

This, however generates heat.

A lot of heat.

As in "Hmm, what's that smell? Oh, my rear brake is on fire. I should probably stop now."
Joe Perez is offline   Reply With Quote
Old 05-20-2012, 11:11 PM   #284
Elite Member
iTrader: (21)
 
Join Date: Jun 2007
Location: Rochester, NY
Posts: 5,684
Total Cats: 555
Default

When's the new battery arrive for top speed testing?
rleete is offline   Reply With Quote
Old 05-21-2012, 09:46 AM   #285
Elite Member
iTrader: (2)
 
fooger03's Avatar
 
Join Date: Jan 2009
Location: Columbus, OH
Posts: 4,132
Total Cats: 187
Default

Quote:
Originally Posted by Joe Perez View Post
Sidebar:

If you disconnect the brake sensor, you can indeed use the rear disc brake as a dyno load in order to calibrate your equipment with the wheel in the air.

This, however generates heat.

A lot of heat.

As in "Hmm, what's that smell? Oh, my rear brake is on fire. I should probably stop now."
LOL, This made my morning.

Did you get it on video perchance?
fooger03 is offline   Reply With Quote
Old 05-21-2012, 12:34 PM   #286
Boost Pope
Thread Starter
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,914
Default

Quote:
Originally Posted by rleete View Post
When's the new battery arrive for top speed testing?
Not until after it ships, unfortunately. The fellow I'm dealing with on this does good work, but he is legendary within the community for procrastination. He's promised that it'll be within the week.



Quote:
Originally Posted by fooger03 View Post
LOL, This made my morning.

Did you get it on video perchance?
No video was running at the time. And fortunately, there wasn't much in the way of flames, just a lot of smoke and a very, very hot rotor. (Bet you've never seen that on a bicycle before.)

So, the lesson here is that bicycle brakes are not as robust as the brakes on a car.
Joe Perez is offline   Reply With Quote
Old 05-21-2012, 01:54 PM   #287
Elite Member
iTrader: (5)
 
pusha's Avatar
 
Join Date: Nov 2009
Location: Miami, FL
Posts: 7,363
Total Cats: -32
Default

Quote:
Originally Posted by 18psi View Post
Time to: HELLAFLUSH IT
wouldn't have been complete without the Lady Guadalupe
pusha is offline   Reply With Quote
Old 05-21-2012, 02:05 PM   #288
Elite Member
iTrader: (2)
 
fooger03's Avatar
 
Join Date: Jan 2009
Location: Columbus, OH
Posts: 4,132
Total Cats: 187
Default

LOL - that rotor probably weighs in at a whopping 2 ounces with design considerations based on stopping half of a 200lb cyclist on a moderate downhill grade from 20mph to zero over a time period of about 2 seconds, or maintaining constant torque on those rotors for that same sized man on a steep to very steep downhill grade at a rate of 2-3 MPH.

If your e-bike ever goes full Toyota on you, you're going to have a rough time slowing it down safely.

Got a kill switch?
fooger03 is offline   Reply With Quote
Old 05-21-2012, 02:33 PM   #289
Boost Pope
Thread Starter
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,914
Default

Quote:
Originally Posted by fooger03 View Post
LOL - that rotor probably weighs in at a whopping 2 ounces
I didn't weigh it when I had it off, but it's pretty light. Very thin steel.



Quote:
If your e-bike ever goes full Toyota on you, you're going to have a rough time slowing it down safely.
Well, even if the motor were to go full-bore, I think I could probably still stop it. During this test, I was dragging the brake at only moderate pressure, applying just enough load to hold the motor at a constant load, thus drawing a constant current so that I could calibrate the controller against an external ammeter.

In an actual panic-stop situation, I'm pretty sure that the brake could stop the motor.


Quote:
Got a kill switch?
Several.

The BCU itself looks at the throttle signal to make sure that it's in-bounds. The maximum output of the throttle under normal conditions is 3.8 volts, so I've told it that anything over 4.2 volts represents a fault condition (eg: short between +5 and signal) and that it should ignore this and shut down.

The rear brake lever is wired to an input on the BCU which also shuts off the output when engaged.

The front brake lever is wired directly to the controller, and behaves the same.

There's a power switch on the handlebars which controls the logic supply to both the controller and the BCU. If this switch is opened, both of them shut down.

And, since this is a brushless polyphase motor rather than a brushed series-wound motor, a short-circuit in the controller's FETs cannot cause a runaway condition. At worst, it would just lock the motor and then burn up the winding.
Joe Perez is offline   Reply With Quote
Old 05-21-2012, 03:32 PM   #290
Elite Member
iTrader: (2)
 
fooger03's Avatar
 
Join Date: Jan 2009
Location: Columbus, OH
Posts: 4,132
Total Cats: 187
Default

Yeah, but what if a series of meteorites makes it into the atmosphere and takes out all of the kill switches, while at the same time, a stray bullet takes out your front caliper, and a mouse chews through your rear brake cable. Then what?
fooger03 is offline   Reply With Quote
Old 05-21-2012, 03:35 PM   #291
Elite Member
iTrader: (2)
 
fooger03's Avatar
 
Join Date: Jan 2009
Location: Columbus, OH
Posts: 4,132
Total Cats: 187
Default

P.S. - it's a mighty mouse - teeth stronger than steel...
fooger03 is offline   Reply With Quote
Old 05-21-2012, 03:41 PM   #292
Boost Pope
Thread Starter
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,914
Default

Quote:
Originally Posted by fooger03 View Post
Yeah, but what if a series of meteorites makes it into the atmosphere and takes out all of the kill switches, while at the same time, a stray bullet takes out your front caliper, and a mouse chews through your rear brake cable. Then what?
Hopefully I would crash somewhere near a lotto machine.
Joe Perez is offline   Reply With Quote
Old 05-24-2012, 10:28 AM   #293
Elite Member
iTrader: (46)
 
Stein's Avatar
 
Join Date: Dec 2007
Location: Nebraska
Posts: 4,812
Total Cats: 138
Default

Quote:
Originally Posted by Joe Perez View Post
The fellow I'm dealing with on this does good work, but he is legendary within the community for procrastination. He's promised that it'll be within the week.
So, what you are saying is that it will ship.....tomorrow.
Stein is offline   Reply With Quote
Old 05-24-2012, 02:08 PM   #294
Boost Pope
Thread Starter
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,914
Default

Quote:
Originally Posted by Stein View Post
So, what you are saying is that it will ship.....tomorrow.
(sound of crickets chirping.)
Joe Perez is offline   Reply With Quote
Old 06-02-2012, 02:19 PM   #295
Elite Member
iTrader: (24)
 
kotomile's Avatar
 
Join Date: Oct 2006
Location: Monterey, CA
Posts: 7,578
Total Cats: 40
Default

How much do you have tied up in this Joe, if you don't mind sharing?
kotomile is offline   Reply With Quote
Old 06-02-2012, 02:54 PM   #296
Boost Pope
Thread Starter
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,914
Default

Quote:
Originally Posted by kotomile View Post
How much do you have tied up in this Joe, if you don't mind sharing?
Hmm. Good question. Hadn't really sat down and done the math.

The bike itself was $475 including tax.
The whole assembly of battery / motor / controller / wheel was HK$$11,700 (about US$1,500) including shipping from China.
The CycleAnalyst BCU was $207 including shipping from Canada.
I re-used the tires, tubes, lights, mirror, etc from the last bike.
Plus maybe $75 total for the rear frame, racks, and all the little accessory bits.

All in all, a lot more expensive than my car.



And I finally got word a couple days ago that the battery has shipped.

(Bloody well time.)
Joe Perez is offline   Reply With Quote
Old 06-02-2012, 03:01 PM   #297
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 36,174
Total Cats: 2,575
Default

*gasp*
18psi is offline   Reply With Quote
Old 06-02-2012, 03:18 PM   #298
Boost Pope
Thread Starter
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,914
Default

Quote:
Originally Posted by 18psi View Post
*gasp*
Hehe.

Like I said a couple of pages ago, I decided to just say "to hell with money" and just do this one right. Hopefully it'll turn out to be a pretty serious performer.
Joe Perez is offline   Reply With Quote
Old 06-02-2012, 09:19 PM   #299
Elite Member
iTrader: (24)
 
kotomile's Avatar
 
Join Date: Oct 2006
Location: Monterey, CA
Posts: 7,578
Total Cats: 40
Default

So $2257 by my math. That's a lot better than the $12k+ I thought I saw when I skimmed your reply, heh.

I'm a little surprised you managed to spend so much on the bike itself. Steel bikes on Craigslist ought to be fairly cheap. But I think if I were in your shoes I'd probably pay the extra and not deal with old components too.
kotomile is offline   Reply With Quote
Old 06-02-2012, 09:30 PM   #300
Boost Pope
Thread Starter
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,914
Default

Quote:
Originally Posted by kotomile View Post
So $2257 by my math. That's a lot better than the $12k+ I thought I saw when I skimmed your reply, heh.

I'm a little surprised you managed to spend so much on the bike itself. Steel bikes on Craigslist ought to be fairly cheap. But I think if I were in your shoes I'd probably pay the extra and not deal with old components too.
Nice things cost money.

I wanted to take this opportunity to upgrade the bike as well. I went with a fairly lightweight aluminum frame which came complete with disc brakes, a decent set of derailleurs, and so on. Figure if I'm gonna spend "real" money on the drive system, I might as well have a decent-quality platform to build on.
Joe Perez is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
2015 NASA Eastern Championships at VIR emilio700 Race Prep 35 09-11-2015 01:23 PM
Checking In! Clayton Meet and Greet 9 10-12-2008 05:41 PM
How to build a car from ground up hrk Insert BS here 8 10-11-2008 05:06 PM
Manifolds and Downpipes cjernigan DIY Turbo Discussion 40 04-19-2007 04:46 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 09:56 PM.