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by John in CR
Jul 01 2008 3:02pm
Forum: E-Bike General Discussion
Topic: Full Face Helmet
Replies: 290
Views: 17472

Re: Full face helmets.

Here in Costa Rica there is socialized healthcare, and there's been talk of repealing the helmet law, because wearing helmets has greatly increased the number of people in accidents who are supported by the state as vegetables instead dead. These helmets, if anything, increase the possibility of get...
by John in CR
Jul 01 2008 1:08pm
Forum: E-Bike General Discussion
Topic: Ecrazyman controller with Kollmorgen?
Replies: 99
Views: 14082

Re: Ecrazyman controller with Kollmorgen?

We should have enough info for no cussing. For the Ecrazyman controller, for clockwise direction, I believe it should be blue-green-yellow for both halls and phase wires, both in a clockwise direction looking at the open motor as in the pics. My fingers are crossed for you. If it spins the wrong dir...
by John in CR
Jun 30 2008 7:19pm
Forum: E-Bike Technical
Topic: kelly killed 1 hall ???
Replies: 29
Views: 3808

Re: kelly killed 1 hall ???

Miles, Yes something like that, but I was thinking taller thinner fins. As subsequently stated though, the heat is on the inside. It looks like there is plenty of room in there and you already have a good thermal conductor to sink heat away from the windings, so you just need to get it out. Signific...
by John in CR
Jun 30 2008 6:50pm
Forum: E-Bike Technical
Topic: Aerodynamics thread?
Replies: 131
Views: 17387

Re: Aerodynamics thread?

The thing we need to come up with is a design on the back side that addresses the acoustical problem with fairings. Truer words are seldom spoken. I removed my full fairing for the hot summer months and my top speed dropped by...1- 2 kph. The noise level dropped immensly to near nothing, quite refr...
by John in CR
Jun 30 2008 12:44pm
Forum: E-Bike Technical
Topic: Aerodynamics thread?
Replies: 131
Views: 17387

Re: Aerodynamics thread?

It doesn't seem like an aerodynamic fairing it terribly difficult. The thing we need to come up with is a design on the back side that addresses the acoustical problem with fairings, and that is, the better the fairing, the greater the concentration and focusing of road noise directly at the rider. ...
by John in CR
Jun 30 2008 10:30am
Forum: E-Bike General Discussion
Topic: Starting an e-bike company - let's figure out the specs :)
Replies: 78
Views: 6871

Re: Starting an e-bike company - let's figure out the specs :)

A crystalyte 408 motor, 20" rim with a 36 volt battery would work out really well with a 35 amp controller. Depending on how far you want to commute (with what you describe, it looks like 10 miles, max) I would say a $400 Li-Po battery would be more than enough for the power supply ($550 for a high...
by John in CR
Jun 30 2008 12:48am
Forum: E-Bike General Discussion
Topic: Ecrazyman controller with Kollmorgen?
Replies: 99
Views: 14082

Re: Ecrazyman controller with Kollmorgen?

Is there any way of knowing for sure if you have the wiring right? I just played around until the thing worked. Now it seems like the motor has a TON more rpms than it did at 24 volts. Of course that was the point of going to 36 volts but I'm just a bit paranoid I'm going to burn something up if it...
by John in CR
Jun 29 2008 10:24pm
Forum: E-Bike Non-hub Motor Drives
Topic: Using RC motors on E-bikes [Archive]
Replies: 1244
Views: 171872

Re: Using RC motors on E-bikes

A two motor system would not be impossible. Maybe that would do everything, high efficiency and high power. Each motor would have its own free or one-way so each could run independently. Matt This is exactly what I've been considering, except the big 6kw RC motor would be my low power / high eff mo...
by John in CR
Jun 29 2008 7:21pm
Forum: E-Bike Technical
Topic: kelly killed 1 hall ???
Replies: 29
Views: 3808

Re: kelly killed 1 hall ???

That aluminum tube shaft isn't going to get you much surface area, and therefore no much heat sinking ability with air. If you want to exchange heat with air in the surrounding environment, then significant surface area is what you need. My thought to keep hub motors cooler is to install a handful l...
by John in CR
Jun 29 2008 12:17pm
Forum: E-Bike General Discussion
Topic: Starting an e-bike company - let's figure out the specs :)
Replies: 78
Views: 6871

Re: Starting an e-bike company - let's figure out the specs :)

Miles, That chainglider has to come with a friction penalty that is likely to tip the efficiency scale toward a shaft, since a typical dirty chain and gears tips that scale far enough. I'm with Michael and throw my vote in for a shaft drive, or maybe even a kevlar belt drive. Either one may result i...
by John in CR
Jun 29 2008 12:09pm
Forum: E-Bike Technical
Topic: Check your nut tightness
Replies: 8
Views: 873

Re: Check your nut tightness

Y'all killin me. :lol: Yeah, the box is a little bigger than I wanted, $ 8 at the local Korean street market. I look like all the locals running around. I add about a 1/2 inch of padding between walls, batteries, on top and underneath. I'm worried about crashing with $ 1,400 of batteries flying aro...
by John in CR
Jun 29 2008 11:54am
Forum: E-Bike Technical
Topic: Freewheel quality and silent freewheels?
Replies: 7
Views: 843

Re: Freewheel quality and silent freewheels?

Upon closer inspection, ie holding it up to my ear, it is ratcheted with barely perceptible clicks. It's a brass colored metal and stamped on one side is "Kangdico China 07 ATA 08". Hopefully it's of decent quality, but I'm concerned because it doesn't spin nearly as freely as other freewheels I've ...
by John in CR
Jun 29 2008 11:27am
Forum: E-Bike Technical
Topic: electronic winding shifting
Replies: 35
Views: 2862

Re: electronic winding shifting

John, that motor is probably the same deal as if you had a slow torquey motor, and you double the voltage to go fast. but since the controllers are buck converters and not buck-boost, they cant increase the voltage, so it would be easier to raise the Kv to get the same effect as a higher voltage. i...
by John in CR
Jun 29 2008 10:52am
Forum: E-Bike Technical
Topic: Geared Regen?
Replies: 27
Views: 4459

Re: Geared Regen?

This is a new idea ... at least no one has found evidence that anyone has tried this yet. Post a link if you spot one. [/color] Safe, sorry to burst your bubble, but regen is quite common in personnel carriers and other ev's used in industrial applications. You can even get golf carts with regen. H...
by John in CR
Jun 29 2008 10:27am
Forum: E-Bike Technical
Topic: electronic winding shifting
Replies: 35
Views: 2862

Re: electronic winding shifting

this seems to be of no use as there doesnt seem to be any way to be able to double the number of windings without increasing the resistance X4, right? Instead of doubling, triple them with a more simple switch that puts them in parallel, which changes the pole count at the same time. At least I thi...
by John in CR
Jun 29 2008 2:06am
Forum: E-Bike Technical
Topic: Freewheel quality and silent freewheels?
Replies: 7
Views: 843

Re: Freewheel quality and silent freewheels?

Miles wrote:Is it a freewheel with a quieter than usual ratchet mechanism or a sprague clutch?
I don't know. When I turn it I can't hear any ratcheting noise at all, but it doesn't spin nearly as freely as the usual ratchet type that I get.
by John in CR
Jun 29 2008 1:31am
Forum: E-Bike General Discussion
Topic: Starting an e-bike company - let's figure out the specs :)
Replies: 78
Views: 6871

Re: Starting an e-bike company - let's figure out the specs :)

If you really want to differentiate your company, then come up with a bullet proof design that is durable enough to come with a 3yr/30,000 mile limited warranty. The "limited" part would cover you with regard to the batts, but at several points in getting started the literature needs to include very...
by John in CR
Jun 29 2008 1:14am
Forum: E-Bike Technical
Topic: Freewheel quality and silent freewheels?
Replies: 7
Views: 843

Freewheel quality and silent freewheels?

Down here all I can get is no name stuff, that I'm sure is made in China, and I often don't have the patience to wait a couple of weeks for an online order, which after shipping costs more anyway. My favorite cheap bike shop (eg $5 for a new tire and tube incl installation and brake adjustment), jus...
by John in CR
Jun 28 2008 11:55pm
Forum: E-Bike Technical
Topic: Check your nut tightness
Replies: 8
Views: 873

Re: Check your nut tightness

DeepKimchi, Isn't that taillight blocked by your shipping container trailer? ie You're running 80V but have almost a 2sqft suction plate at the back slowing you down. A more aerodynamic tail shape at the back of your batt box instead of that tractor trailer rig shape will probably net you at least a...
by John in CR
Jun 28 2008 8:54pm
Forum: E-Bike Non-hub Motor Drives
Topic: Using RC motors on E-bikes [Archive]
Replies: 1244
Views: 171872

Re: Using RC motors on E-bikes

eP,

Are RC motors quiet in the 4krpm range. I'm hoping the big HXT outrunner is, but I was under the impression that they weren't.
by John in CR
Jun 28 2008 8:50pm
Forum: E-Bike Technical
Topic: Geared Regen?
Replies: 27
Views: 4459

Re: Geared Regen?

I'm sorry Safe, but your over-simplification which includes 250lbs of batteries could never result in something considered extreme efficiency. If you have hills significant enough to require lots of braking, then yes you can make a good case for regen, and yes gearing is likely to help you get up th...
by John in CR
Jun 28 2008 10:46am
Forum: E-Bike Technical
Topic: Geared Regen?
Replies: 27
Views: 4459

Re: Geared Regen?

Doing Some Math... Let's say you get some of the new Firefly SLA batteries that last three times as long as standard SLA. Each one is 70 lbs and delivers 107Ah @ 5 amps. Using four of these ( 280 lbs ) on a trailer and using gears so that on the hill climb you can gear down and on the downhill you ...
by John in CR
Jun 28 2008 10:18am
Forum: E-Bike Technical
Topic: 20" hub cut to 16" Will it work?
Replies: 48
Views: 3292

Re: 20" hub cut to 16" Will it work?

36-48v? I thought this was for the kids. I plan to only let mine use it at 24v. I picked up a tiny 16" bike for nothing. Hopefully today I can extend the rear end and redo the seat setup for a kids ebike that an adult could ride in a pinch. More wheelbase, space for batts under comfy seat w/backrest...
by John in CR
Jun 28 2008 2:07am
Forum: E-Bike Technical
Topic: electronic winding shifting
Replies: 35
Views: 2862

Re: electronic winding shifting

I wonder what would happen if you reduced it to one switch on each phase, just the one at the output end. Then when that switch is closed only a small portion of the current will flow through the secondary coils. I'm with Ep and question the point, since it doesn't enable you to run any more current...
by John in CR
Jun 27 2008 11:11pm
Forum: E-Bike Build Threads / Photos & Video
Topic: The E-cumbent - A project by Matt Shumaker
Replies: 487
Views: 59953

Re: The E-cumbent - A project by Matt Shumaker

Matt, Miles, and Gary, What specifically separates cheap outrunners from expensive ones? Is it in the construction of the laminations of the stator? My plan is to use the biggest HXT with the 130KV winding. I look at these motors and see the only potential point of failure being the bearings, so I w...