Greetings to all - from a downunder tinkering enthusiast

Discussion in 'Introduce Yourself' started by madact, Jun 12, 2010.

  1. madact

    madact Member

    G'day, I'm Yuri, and I like building things

    Gee, that sounds a bit AA now that I type it... pretty appropriate, I guess, I have way too many projects on the go at any given time, and always seem to be running out of time, money or space - but things do get done... eventually :rolleyes7:

    Anyhows, about me: male, a coupla years off 30, tinkerer, like I said... I finished my B-Eng. (Comp. Sys) about 4 years ago, but did all the magnetics and electrical machines electives cos hey, I like it when big lumps o' metal go BZZZZTwoooooOOOOOIIIIIIEEEEEeeeeee(sssssssssssss) :grin5:. Was heavily involved with the "pedal prix" at high school (big recumbent faired trike race, now called the HPVSS: - best teams are knocking on 1000km in 24 hours on a crowded criterium course) which I plan to get back into next year - another of my projects on the go right now.

    Joined this forum 'cos I'm starting up building a liddle halbach axial flux motor to fit on a bicycle - we have a (nominal) 200W limit here in S.A. before you need license and rego, but judging from the info sheets from our transport department, the law appears to be that the thing has to look like it's under 200W :whistling:. In any case, easy enough to comply by fitting a 200W controller, and I haven't the figgiest what it my build will put out, yet. It'll be a handy hill assist for commuting in an HPV, too.

    Further down the track, I'd like to build a few ~10-15kW car wheel motors on the same principles, based on experience gained in the small scale. I have a friend interested in EVs who I'm hoping to collaborate with... The CSIRO motor was only limited to 1.8kW because that's the power available - that sucker can scale :evilgrin: and their thermal margins are probably good for another 2kW of peak loading as built (for, oh, 5-10 seconds or so, maybe more depending on materials). But that's a job for another year, most likely...

    Anyhow, good to meet y'all, looking forward to some good advice and discussion,

  2. AussieSteve

    AussieSteve Active Member

    Welcome, Yuri.
    Looks like we have similar interests. I'm always building something and also have a sparky background - electronic design and repair.
    Besides my 2-stroke bike, I've got a 200W electric, too, but nothing as exotic as a Halbach motor, just a simple brushless hub motor with 36V 10Ah LiFePo4 battery. I only weigh 50kg, so it gets me around fine. With front and rear suspension, although it's slow, it's my limousine. The 2-stroke is noisy and shaky, like riding a paint can shaker, but faster and more fun than the electric. (There are pics of both in the album on my profile page, if you're interested.)
    I'll be interested to see how your build progresses.

    Which part of Oz are you in? (I'm in Nowra, NSW.)
    Last edited: Jun 12, 2010
  3. madact

    madact Member

    Hi Steve,
    I'm in Adelaide (well, Adelaide suburbs, but only 4km from the CBD...). This is my first foray into powered bikes, so no pics yet, I just have a couple of pushers - a racer and an MTB - and I'm just starting the faired recumbent trike. I'm about 110kg, (with a healthy weight not less than 100), so I don't know that 200W will be getting me up any hills...

    I like the unsuspended battery pack on your electric, not so sure about the drive setup on the 2-stroke - or do you have a freewheel on your pedals / chainrings?

    Where can you get LiFePo4 batteries at a decent price around here, anyway? Best I've seen is over $400 for something like that, I've been considering just using RC aircraft LiPo battery packs, I can get about 3x the kWh per dollar, not so sure about the battery lifetime though...

    P.S. I've started a thread for my project in the 'motors' section
    Last edited: Jun 12, 2010
  4. AussieSteve

    AussieSteve Active Member

    There are heaps of MBc members from Adelaide - more than any other state for some reason.
    Not many hills on my usual shopping route, so 200W isn't too bad at my weight. I never have to pedal if I don't want to, but a bit of pedalling on hills helps keep the speed up.

    Yep, you got it in one - a freewheel on the chainrings. The chainrings are always turning while the clutch is engaged, but the pedals aren't. Works well. Turns an MB into a multi-speed moped. (6 gears in my case.) I can idle along at 8kph in 1st or wind out to about 80kph on a slight downhill in 6th.
    (I don't actually go quicker than 50kph, in reality.)

    My electric bike came complete, with the Lithium battery, so I didn't need to find a separate source. A replacement battery to suit is $400. it came stock with an 8Ah lead-acid battery and the upgrade to Lithium was only $80 so I jumped at it. (I bought the bike from ZBike (Australia))

    I forgot to add, if you haven't already found it, Endless Sphere is another good site for electric bike enthusiasts.
    Last edited: Jun 12, 2010