Search results

Date Relevance Most replies

  1. Erogo

    Friction drive - 1kW junkyard sunday afternoon project -

    Or, how about the two motors contact the RIM, to get less churning loss? Some frames even have pivoty brake mounts that you could pivot a pair of motors off, and rig a squeezing cable between them.
  2. Erogo

    Motorcyclist clocked at 193 mph on NY highway - in the rain!

    Ha ha good call Tyler. Yeah, society sets up laws that reflect the desire of the majority of its citizens. Some of them are preventative, targeting some situations of increased risk - driving drunk, driving too fast, leaving babies at home unattended etc etc. Presumably the citizens of that...
  3. Erogo

    Good! Someone finally oil cooled a hubbie!! HS3540

    The right epoxy, and the right oil. The oilbath fella tested his oil before sticking it in his motor. Nothing if not thorough, that fella.
  4. Erogo

    Excel friction drive prototyping tool

    I've made a spreadsheet up that does various figuring out for friction drives. It calculates the force required between the roller (motor can) and the wheel, under different accelerations, rider weights, gradients etc. It estimates what the actual RPM of the motor will be, given the kv and the...
  5. Erogo

    Very Simple String-Capacity Question

    "String" seems like a bad word to use for paralleled cells. A string would normally imply series cells. Like a string of sausages. That and the fact that you had to say makes it seem like you're confused between parallel and series! Be careful! Eric
  6. Erogo

    Please help with Electricity Math

    I'd strongly recommend heatsinking the lipos against the petrol tank. The mass of fluid within should keep the lipo at an optimum working temperature, ensuring you get maximum life from them. Probably using the metal of the petrol tank as a common earth is a good idea as well, you can use your...
  7. Erogo

    Please help with Electricity Math

    Hmm, that doesnt sound too bad actually does it vokus! And as Hillhater pointed out, your 700w is probably max, so you'd get more than your five hours out of it. Or you could run somethign else off it at the same time, like a decent sound system. You'd have to power a screen of some sort as...
  8. Erogo

    Please help with Electricity Math

    700 watts for five hours? You need 3500 watt hours of capacity. If you get your lipo seriesed up to deliver 120V, then your 700 watts will be drawing about 5.8 amps. So you need to deliver 5.8 amps for five hours? 29 amp hours. Most packs are speced in milliamp hours, so you need to get...
  9. Erogo

    Commuter Booster - <1kg Friction Drive

    Hey Adrian, good to hear the progress! I hope you're having fun, with it so close to completion. My two cents: 1) Youve got wiring to the front already hey, for the display? It might not be too much more hastle to have another pair for the wheel sensor? Would the extra length be subject...
  10. Erogo

    Joby Motors Santa Cruz, CA

    That sucks eh. We're all (ok 99% of all) shopping by cost, buying the cheapest we can find, bleating when the $60 WangFo motor that some kid put together at 2am working for a dollar a day doesn't have it's windings tied down tight, and uses an economy grade bearing. Who was it said: "Noone...
  11. Erogo

    How cr4ppy?

    OK I think it's an ezipp Made in India, rated at 250w with 48v of SLA The one in the shop sold, but get this: There's another one available because the original purchaser has given it away to the local women's refuge, who don't want it either. So they dont know how to get rid of it, being...
  12. Erogo

    The Brevette "Winchini": a push baby-trailer

    Did some more sawing and drilling and filing last night. Cause I found that when I bolted the newly secure motor to the trailer, the wheel couldn't go round any more. I traced it to the fact that the new retention plate was pressing hard against the tire. Stink. The thing's getting too big...
  13. Erogo

    battery health by listening to it?

    You're not using sound waves anyway, you're using radio waves. But, go ahead and isolate the charger from the experiment by placing it in a faraday cage if you have one handy, or just shielding it in copper. I'd lend you the copper hat I use to prevent the government beaming their messages...
  14. Erogo

    Nuvinci developer kits for cheap

    Hey McLovin - what about the insides ;-)
  15. Erogo

    How cr4ppy?

    Ah, but headaches is what life's all about, isn't it? If you can always get what you want, you don't appreciate it any more. Yes, this is just a hubmotor in a small wheel. I reckon it should be midmountable, via some sort of bodgy bracketing and lots of duct tape. As a moped styles, it's...
  16. Erogo

    How cr4ppy?

    Yeah the old junk yard hat is pretty well-worn. You've seen my Brevette Winchini build maybe. This could be a good alternative approach to motivating the baby trailer, if I wasn't so far down the current path already! The motor would be a bit tricky to lace, being one piece casting out to the...
  17. Erogo

    How cr4ppy?

    That was what I was thinking last night. If the magnets are really shiny, I'll get it. Do you think there's any possibility they're just using ferrite magnets? I guess anything's possible eh. $250 : approved in advance by my exceptionally encouraging and supportive partner : isn't...
  18. Erogo

    How cr4ppy?

    Yeah nah, I think I might be wrong about that "Ezee" bit. It wasnt heavily plastered with brandname, kinda anonymous looking. Generic almost. Like they were trying to hide something, or at least not sign their name to it. I think I'll get it. I mean, NZ$250? The batteries alone have to be...
  19. Erogo

    lit motors c-1

    For me that would depend on the total package. On-road costs, warranty, insurance cover, public liability, service agreement etc. If the price was right.
  20. Erogo

    lit motors c-1

    Hey PTD, I'm not a gyroscope expert by any means, but I don't see what the forces in the other two planes are. My understanding of a gyroscope is a mass spinning on an axis. The axis lays on one dimension. If you apply a torque to the axis in a dimension orthogonal to the axial dimension, a...
  21. Erogo

    Brushless razor e300

    Did you say the motor has a 1mm shaft? If so, that seems real small to me. I'm more used to bicycle loads, where I think 8 mm or so is needed. You can calculate the torque that the shaft would need to withstand to achieve the acceleration you're hoping for, then calculate the maximum torque a...
  22. Erogo

    How cr4ppy?

    But, but, they were originally trying to sell them for $1000 or $2000 or something, and this is the last one left. Surely it's really good eh? It's called an ezee scooter or something. The name on the forks is "no comeback". Odd.
  23. Erogo

    How cr4ppy?

    Wondering: "How crappy can an e-scooter get?" The LBS has one new for 250 of our local dollars. That's about, what, US$180 or something? It's 48v, can only assume PbH+, and is probably compliant with NZ law on electric bicycles, which I can't remember (don;t care) whether it's 300w max or...
  24. Erogo

    The Brevette "Winchini": a push baby-trailer

    thanks Pony. I got another bit done, which is the main retention plate. Simply a fold of aluminium, screwed to the end of the stub of shaft that sticks into the nylon bit that's bolted to the chain ring, and also screwed to the gearbox housing through a little flange bit I hadnt noticed...
  25. Erogo

    lit motors c-1

    Yes (in a standard bicycle at least) it has been shown that the gyroscopic effect of the wheels, while traditionally believed to be essential to self-stability, is in fact not necessary. Gyros designed for the purpose have to be a different story though! I posted a link to a paper describing a...
Back
Top