Search results

Date Relevance Most replies

  1. D

    Going LiPo - Advice Required

    Since we're talking LiPo basics, am I correct in assuming that when wiring packs in parallel, also wiring the balancing connectors in parallel could help to keep the individual cells in balance? I presume the balancing connectors are there primarily for use during the charge cycle with...
  2. D

    Does this count as belt drive?

    Yeah, I don't understand... they presumably worked out some way to drive the rear wheel off the belt, they welded half a bike to the front of it, and worked out a way to steer from behind, but they couldn't figure out how to remove the power cord?
  3. D

    Full Suspension Frames for E-Bikes?

    Generally speaking, the multi-link designs that put the pivot point higher with the crank on the rear arm are the designs that tend to minimize bobbing. An example is the GT i-drive.
  4. D

    BMC V2 with 8 speed freewheel?

    From what I've read, it will accommodate a 7spd, but an 8spd might require spreading the rear triangle. I don't want to do that, as mine is aluminum, but I do want to confirm the 8spd won't fit before I order. I've put the motor on the frame, and it seems to fit well... the flattened portions...
  5. D

    7 Police Cars to Detain Man on Electric Bike

    I'm not sure I follow the posts that say the biker was at fault for removing the pedals... the bike in the video *I* saw had pedals. So I guess what you're saying is: we should grade on a curve? :shock:
  6. D

    BMC V2 (600w) & disc brakes

    Well, by the time I confirmed that a 185mm rotor would fit on my bike with a motor, pricepoint ran out of the 2008 185 BB7 sets they had for cheap. So I got a 160mm rotor. Guess some tab bending is in my future.
  7. D

    BMC V2 (600w) & disc brakes

    Thanks for the info! Without yet having the brakes, I can't visualize the part you had to bend, but it sounds like it wasn't a big deal? Is it safe to assume that shifting to the 185mm rotor would be enough to make this clear the motor, while possibly increasing the risk of clearance issues...
  8. D

    BMC V2 (600w) & disc brakes

    I know some motors have caliper clearance issues with certain brakes and certain size rotors. Does anyone have any experience specifically with the BMC V2 and Avid BB7 brakes? I know if it's tight, going to larger rotors may help get the caliper out away from the motor, but going too large MAY...
  9. D

    Blew out sensorless ctrlr again-- what's reliable?

    Has anyone found a decent, affordable sensorless controller that can handle 72v?
  10. D

    Changing out freewheels

    Perfect, thanks!
  11. D

    Changing out freewheels

    I have a BMC 600T that I'm going to be mounting on a 24sp full suspension aluminum framed MTB. The 600W BMC is advertised as working with 7sp freewheels, or 8sp if you don't mind spreading the rear triangle. But being aluminum, I don't think that's a good idea. I'm assuming I'll have to buy a...
  12. D

    mtb with 24 volt lawnmower motor

    I have one of those old 24v B&D cordless mowers... I had to take it apart once to fix something, can't remember exactly what. But from what I remember, it had a pretty open framed motor with very exposed windings, and was brushed, IIRC. Probably not something you'd ever want to take out if...
  13. D

    An ebike for the hills?

    Yes, the comparisons I made were based completely on the power it takes to do the work, and completely ignores changes in efficiency of the drive system under different conditions. That will vary depending on the set-up, so it's hard to include it in the comparison. But in a situation where...
  14. D

    An ebike for the hills?

    Just to continue this interesting tangent for a bit... :mrgreen: To get your mass up a hill, ultimately, the same amount of work has to be done regardless of how fast you do it. So the only variable factor in any case is wind resistance. Because of the exponential effect of speed, doubling...
  15. D

    Clever "Contortionist" Folding Bike Design - pics and vid

    No, if you watch when it folds, that part folds completely with nothing inside.
  16. D

    Clever "Contortionist" Folding Bike Design - pics and vid

    I don't think they do. This appears to be more of a proof of concept than a fully operational bike. In the video, it seems fairly clear that there's no connection between the crank and wheel.
  17. D

    Outrageous 120 kph claims?

    I'm a bit skeptical... doesn't look like he's doing 75MPH in that video. I know *I* wouldn't want to go that fast on a bicycle, especially one with a chain drive on the motor. I can't imagine the drivetrain lasting long under that kind of duty (nor the rest of the bike). There was a fatal...
  18. D

    Soldering tab-less 26650VT ok?

    Thanks, that's what I was thinking too. I can see the value in that if soldering batteries end to end, but I intend to do mine in more of a zig-zag... one cell standing up, connecting to another right next to it upside down, with some thin copper strap connecting them. In other words, I'm...
  19. D

    Soldering tab-less 26650VT ok?

    Thanks for the replies! I've determined that silver bearing solder (62% tin 36% lead 2% silver) would be the best choice... it has the lowest melting point of the common solders (179°C), is eutectic, and the silver increases the strength a fair amount. I was going to get a Weller WLC-200, as...
  20. D

    bmc hub 600w is Toast

    Can't explain the June vs. Jul/Aug issue (unless the gas stations hadn't yet switched to their "summer" fuel). But the water bottle part is most certainly due to the evaporative cooling of the water (which can be substantial), rather than differences in specific heat of humid vs. dry air...
  21. D

    bmc hub 600w is Toast

    Are those holes "stock"? Odd that the rubbing just happened to be in the same area as the holes. Could they have weakened the houseing, causing it to bow out a little in that area? I'm not familiar with this... water does have a much higher specific heat than air, but it's in such small...
  22. D

    Soldering tab-less 26650VT ok?

    I have a bunch of these batteries I need to build into a pack. They have no tabs. How much risk is there is soldering copper strap directly to the batteries? If you solder quickly with enough heat, will they be OK, or are you likely to damage the batteries?
  23. D

    Best riding tire

    On the surface, that seems like a very poor test if you're trying to determine rolling resistance. For one thing, without a real load on the tire (a person), there's not going to be enough flex in the wall to determine how much flex resistance it has. It would also skew the results towards the...
  24. D

    BMC V3 -- Infineon Build

    I'm assuming you mean series, not parallel? 3 packs in parallel would be a 5s3p pack, which would be a nominal 18.5v 15ah. 3 packs in series would be nominal 55.5v 5ah.
  25. D

    General question about hub motors...

    The commutator does that in a simple brushed DC motor, and it's still considered a DC motor. :wink:
Back
Top