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  1. #1
    ballbuster
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    Electric assist questions...

    Is it me, or does nobody make a rear wheel that takes a regular cassette, and takes a disc rotor? Thread on cassettes suck. I want to use my LX dual control shifters if possible, but they are 3x9.

    I dont wanna drop $1600 on a Bionx kit. It may be really well designed stuff, but that price of entry is way above my pay grade.

    Also, why won't anybody publish the OLD size of the wheels? I only found one that takes a disc brake rear, but it's 150mm rear axle size. What the flip?!? I'm not putting this on a DH bike. I found a bunch of front wheels that are 115mm. Huh?!? Why can't they use established bicycle standards?

    I've googled my brains out on this. I hope somebody can point me in the right direction.

    *edit*

    Okay, if I just go front drive, many of my issues are solved... so, I'm going front drive.
    Last edited by pimpbot; 10-01-2012 at 09:56 PM.

  2. #2
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    In my limited research, it appears that the Bionx was the only one that I could find that takes a disc rotor- I didn't look into the cassette aspect though.

    It's tough to figure out what is quality and what isn't when it comes to electric drive kits, I'll say that much. I'm kicking around the idea of going electric on my Big Dummy in the next year.

    I'm just curious about the handling effects of a front drive system versus rear drive- like, is there discernable torque steer, is it more likely to wash out because the front isn't weighted like the rear, etc. Or maybe pertaining to what I just mentioned, those aren't really factors depending on how powerful the system is.

  3. #3
    ballbuster
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    Quote Originally Posted by XJaredX View Post
    In my limited research, it appears that the Bionx was the only one that I could find that takes a disc rotor- I didn't look into the cassette aspect though.

    It's tough to figure out what is quality and what isn't when it comes to electric drive kits, I'll say that much. I'm kicking around the idea of going electric on my Big Dummy in the next year.

    I'm just curious about the handling effects of a front drive system versus rear drive- like, is there discernable torque steer, is it more likely to wash out because the front isn't weighted like the rear, etc. Or maybe pertaining to what I just mentioned, those aren't really factors depending on how powerful the system is.
    I would think if you're applying lots of power in a tight turn with limited traction (gravel, wet, steel trench plates, wet painted vinyl street marking lines, etc) then yes, it will likely wash out. It doesn't seem like that is likely to happen out of the clear blue sky unless you have some sort of smart pedal boost that decides to apply power at the wrong moment.

    I don't foresee any situations where I'm going to be cornering so hard I lay the bar to the ground, weight on the outside pedal, dual slalom style while applying power. Maybe during emergency maneuvers, but again I don't see applying full throttle in those situations.

    Torque steer should not be an issue. Torque steer in FWD cars is cause by uneven length driveshafts applying power unevenly when the front of the car lifts up under acceleration. I think (from my uneducated armchair) that the bars might fight to pull straight a bit under power, but I would think I'm going mostly straight anyway when I want the motor to pull.

    Man, I really have to find a FWD e-cargo bike and try it out. Most of them are 250W, so I can't imagine it pulls that hard. If I bothered to build a wheel myself, I might shoot for at least 350W.

    I've found a bunch of low rent hub motors that have a disc mount. I'm not sure I want to give up my disc brake, being that I have a set of Shimano LX Dual Control hydraulic levers (my preferred method of shifting), my steep hills, my 208 pound uh... self, and possibly hauling two kids and stuff on the back of the bike... maybe even a trailer. I want big rotors to be able to stop all of that mass without smoking the brakes.

  4. #4
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    An issue that can arise with FWD motor on a standard bike is that the front end can be quite light leading to potential wheelspin uphill or under hard acceleration.

    On a long bike the extra weight over the front end should greatly lessen that tendency.

  5. #5
    CP
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    how about this?

  6. #6
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    A mid drive system that feeds into your drivetrain, yet still allows you to pedal, makes a lot more sense to me than a hub motor and solves the weight bias issue at the same time.

    This one is a good bet: mid 450W (brushless)
    Forum info here: Endless-sphere.com • View topic - GNG, 1000W 48V BB-drive, $400
    A bike by any other name is still a bike.

  7. #7
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    Ah yes, electric assist. I've been contemplating this for my Big Dummy since I bought it. I always planned to get the StokeMonkey, or then there is the M-Drive kit:

    Urban Commuter Store

    The maker of this was supposed to be working on a Big Dummy version of the mount but I haven't seen any updates.

    If I move forward with this, I will go front drive built into a Surly Large Marge rim, mainly so that I can keep my exisiting rear IGH wheel and swap out the motor wheel if necessary.

    defintely check these guys out if you are looking to do a conversion.

    www.ebikes.ca Homepage of the revolution

    Justin is the guru of electric assist and can help

  8. #8
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    I would love a mid-drive on my Pugsley.

  9. #9
    somewhat schizophrenic
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    Just bought a Transport+ with the Trek/Bionx kit and the bike is a riot to ride. The only odd handling is in tight, low-speed turns...it can upset your balance a bit if you're not ready for it. Otherwise the assist is helpful but benign. I do believe the cassette is thread-on though. :-p

    Of course, it would have been well out of our price range without the huge discount....

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