Search found 7271 matches

by Chalo
Jun 12 2009 8:17pm
Forum: E-Bike Technical
Topic: Danger of plug braking?
Replies: 38
Views: 2947

Re: Danger of plug braking?

Call me old-fashioned, but i cant see the attraction. I got a rear 24" motor/wheel that wasn't compatible with my mountain bike frame v-brake. Installed a plug brake (in like 10-15min) and it works smoothly and flawlessly. It's not complex in the slightest, works amazingly well and solves certain p...
by Chalo
Jun 12 2009 5:01am
Forum: E-Bike Technical
Topic: Danger of plug braking?
Replies: 38
Views: 2947

Re: Danger of plug braking?

If you aren't even getting regen from the front braking, what is the point? Brakes are simple and light and easy, and don't apply any loading to the weak axle point connection. Call me old-fashioned, but i cant see the attraction. - No wear parts - No adjustment - Inherently anti-lock - Easily limi...
by Chalo
Jun 07 2009 7:37pm
Forum: E-Bike General Discussion
Topic: very large flickr photo of two Pi ebikes, interesting
Replies: 18
Views: 1548

Re: very large flickr photo of two Pi ebikes, interesting

I'd really need to see one in person, but there's something about the angle and placement of the headset pivot relative to the wheel and fork that doesn't feel quite right to me. Look at the joint between the fork and frame on the bike in the near field, and think about how that has to turn. I may ...
by Chalo
Jun 07 2009 6:42pm
Forum: E-Bike Technical
Topic: Danger of plug braking?
Replies: 38
Views: 2947

Re: Danger of plug braking?

Speed = RPM*circumference. Kv = RPM/V -> V = Kv*RPM= Kv*(speed/circumference) I = V/R (R being motor resistance) = Kv*(speed/circumference)/R Torque = k*I = k*Kv*(speed/circumference)/R. Force = Torque/radius = k*Kv*(speed/circumference)/(R*radius) (radius would correspond to the middle of axle and...
by Chalo
May 27 2009 2:45pm
Forum: E-Bike Technical
Topic: LIVE switch vs KILL switch
Replies: 21
Views: 2407

Re: LIVE switch vs KILL switch

On my wife's e-bike (with a WE brushed hubmotor and a Curtis controller), I installed a big 75A pull-on/push-off switch right on the top tube, in one of the motor leads. I thought to do this because the Curtis controller features off-throttle electric braking whether powered or not, and I wanted her...
by Chalo
May 06 2009 2:40pm
Forum: E-Bike Technical
Topic: i've invented a new technique for using hot glue!
Replies: 4
Views: 715

Re: i've invented a new technique for using hot glue!

You should try Shapelock. It's UHMW polyethylene pellets that can be turned into a soft putty in (very) hot water, then molded into whatever shape. When cool, it's very hard and strong compared to hot glue, and it has no tackiness at all. http://shapelock.com/page5.html I have no relationship to the...
by Chalo
May 06 2009 11:50am
Forum: E-Bike Technical
Topic: I want throttle to be more like on an ICE
Replies: 19
Views: 1399

Re: I want throttle to be more like on an ICE

I can't see how using a closed current loop would make the controller any less robust... Can you explain? There are just more layers of complexity between the user's input and the motor. The logic layer in particular would be hard to diagnose as having a problem (until after it did something errati...
by Chalo
May 03 2009 7:02pm
Forum: E-Bike Technical
Topic: I want throttle to be more like on an ICE
Replies: 19
Views: 1399

Re: I want throttle to be more like on an ICE

And I don't really know what you mean here, Chalo: Justin could make it happen, but I'm guessing he won't. The opportunity for a total loss of rider power control (that is, for the controller to "fail on") would keep me from selling it to the public for a reasonable price. I can't see how using a c...
by Chalo
May 02 2009 7:01pm
Forum: E-Bike Technical
Topic: I want throttle to be more like on an ICE
Replies: 19
Views: 1399

Re: I want throttle to be more like on an ICE

I'd like to make the throttle for an electric behave more like on an ICE car or motorcycle. For example, I want to have more current capability on tap, so when I want to accelerate faster I can do so instantly and variably. I want to be able to control this extra performance, so once I become accus...
by Chalo
May 02 2009 2:35am
Forum: E-Bike Technical
Topic: LED lighting question
Replies: 26
Views: 2671

Re: LED lighting question

I like how my light has a blink mode, been debating getting a 2nd one and putting a red filter on it for the back, it's so bright there's no way they could ever say they didn't see me - heck you can see in the DAYTIME! It's a bad idea use a red filter on a white LED, for two reasons: 1) White LEDs ...
by Chalo
May 01 2009 8:37am
Forum: E-Bike Build Threads / Photos & Video
Topic: Chopper "Electra"Glide
Replies: 17
Views: 5208

Re: Chopper "Electra"Glide

Interesting gear shift location........ :wink: One of my buddies in Seattle puts his SRAM twist grip on the seat post itself. 22.2mm is the old standard BMX and cruiser seat post diameter, as well as the normal diameter for all handlebars other than drop bars. http://www.deadbabybikes.org/bikes/300...
by Chalo
May 01 2009 8:29am
Forum: E-Bike Technical
Topic: Chromed aluminium rims, are they OK?
Replies: 12
Views: 966

Re: Chromed aluminium rims, are they OK?

ElectricEd wrote: BTW, is that a live cat or a hat?
He's both, at least from time to time.
by Chalo
May 01 2009 1:55am
Forum: E-Bike Technical
Topic: Chromed aluminium rims, are they OK?
Replies: 12
Views: 966

Re: Chromed aluminium rims, are they OK?

Found a supplier for the rims.... http://www.torpedo7.com.au/products/AXRIRW724/title/ALEX-DM24-Rim Careful-- that's a 24" rim (ISO 507). If that's what you want, great, but the normal MTB size is 26" (ISO 559). Maybe that supplier stocks both. My earlier URL got munged. The correct one is http://j...
by Chalo
Apr 30 2009 2:25pm
Forum: E-Bike Technical
Topic: Bafang SWXH Repair Opening One Up
Replies: 46
Views: 9034

Re: Bafang SWXH Repair Opening One Up

New Problem with my freewheel tool I bought. I'm starting to wonder if this is all worth it :x I can't seem to drill a hole in it so I can get it over the Banfag axle. See pics. Cobalt drill bits didn't work. What kind of freewheel removal tool do you guys use? I have opened up the bores and/or cut...
by Chalo
Apr 30 2009 2:11pm
Forum: E-Bike Non-hub Motor Drives
Topic: Best wheel size
Replies: 21
Views: 3581

Re: Best wheel size

Oh, so a gear ratio of 12 is within the province of practical? I thought Matt was saying something about "Keep it under 6 per stage" or some such like that. My first e-bike had 12:1 reduction in one stage (#25 chain with 144t and 12t sprockets). There were issues that made me move on to the next ve...
by Chalo
Apr 30 2009 12:39pm
Forum: E-Bike Technical
Topic: Chromed aluminium rims, are they OK?
Replies: 12
Views: 966

Re: Chromed aluminium rims, are they OK?

I'm looking for a new rim for my 408. I've hit a few bumps and the spoke nipples have started to pull through in two places. I am looking for a stronger more durable rim. The LBS guy recommends I get a dual wall chromed aluminium rim that is used on downhill MTBs. I am wondering, under normal circu...
by Chalo
Apr 30 2009 1:49am
Forum: E-Bike Non-hub Motor Drives
Topic: Best wheel size
Replies: 21
Views: 3581

Re: Best wheel size

What do you guys think the best wheel size for the "driven wheel" is? I'd guess a smaller wheel! I wondered why bicycles have 26" wheels to begin with, though. I thought maybe it was to help handle pot holes or something like that, so I went to a motorcycle wheel seller and it seemed 18" was the mo...
by Chalo
Apr 30 2009 12:37am
Forum: E-Bike Technical
Topic: How do you parallel a switch?
Replies: 6
Views: 682

Re: How do you parallel a switch?

As others have pointed out, that's not the right kind of switch to wire parallel for more capacity.

I use this switch for high amp loads:
http://www.robotmarketplace.com/products/0-SW75.html

Chalo
by Chalo
Apr 30 2009 12:23am
Forum: E-Bike Technical
Topic: 12G Spokes
Replies: 16
Views: 1839

Re: 12G Spokes

Can anyone tell me where I can get a "dye" (i think that is what it is called) for cutting threads on the end of 12G spokes, it seems easy to get one for 14G, but not 12G. What are you trying to accomplish? With the same rim, a wheel with thick spokes will loosen and come out of true at a much lowe...
by Chalo
Apr 30 2009 12:12am
Forum: E-Bike Technical
Topic: Wheel lacing for left drive sprocket
Replies: 15
Views: 1583

Re: Wheel lacing for left drive sprocket

A thought on hub stress. Because of the way a wheel is dished, the ds spokes get more stress then nds. You can feel this easely just by grabbing a wheel and feeling the spokes. I used to wonder why on high end wheels the nds is radial and the ds is crossed, I would have thought doing it the other w...
by Chalo
Apr 30 2009 12:03am
Forum: E-Bike Technical
Topic: Wheel lacing for left drive sprocket
Replies: 15
Views: 1583

Re: Wheel lacing for left drive sprocket

Your post prompted me to join this forum, which I had only ever lurked on before. I like your left-side drive solution. My first e-bike used a RH/LH hub for two separate freewheeling drivetrains. I machined a 144 tooth #25 chain sprocket which I bolted to a 16T southpaw freewheel with special rings ...