Puma v Heinzmann question.

General Discussion about electric bicycles.
Lowell   1 MW

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Post by Lowell » May 17 2007 4:44pm

Now that the nice weather is in full swing (25c out the other day!) here, every manner of 2 wheel device is now on the road. It's pretty funny passing 50cc scooters on a mountain bike. :lol:

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Drunkskunk   100 GW

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Post by Drunkskunk » May 17 2007 4:53pm

I don't think there is any real danger of the gears jamming, even if they are steel. Shredding, sure, but jamming isn't likely unless you aren't moving when it happens.

Think of your back tire as level. a 26inch tire is 13 inches from the road to the axle, therefore any torque aplied to the wheel to make it spin is multiplied 13 times at the axle. Now imagine the force being aplied to the wheel through momentum if a 200lbs rider is moving along at 20mph. I say imagine because I can't put my hand on the formula right now. Needless to say, its on the magnitude of several thousand pounds on those little gears if they try to jam.

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knoxie   10 MW

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Post by knoxie » May 17 2007 5:54pm

Hi Drunk, Lowell

Yes I agree on the force at the wheel, when my USPD chain popped over the side and went tight it snapped instantly didnt lock the wheel at all and I was only doing 5mph, this was chain that had 250lb breaking strain!

As for mopeds :lol: well its cheeky to do it but yes, just a year ago I could get my ass whipped on my std 17mph USPD bike by a fit lycra dude even on some slopes, now I have the choice of 4 rides all capable of 40mph+ the little gassers are not only slow top speed 30-35mph, they accelerate poorly as well, even a moderate e-bike should be able to out accelerate them.

Mopeds esp young kids dont like it at all you have to watch them as they often do stupid things trying to catch you! I will go out again on the 26 Incher 43mph bike and mount the head cam and see If I can film me blow a few away! ha ha, lycras are not even worth it now, infact I often let them go as its not worth it, mopeds are a much fairer race for me! That said I dont ride my e-bike at silly speeds in built up areas I am careful.



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Toorbough ULL-Zeveigh   10 MW

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Post by Toorbough ULL-Zeveigh » May 18 2007 2:25am


3 states of euphoria?


–noun Psychology.
a feeling of happiness, confidence, or well-being sometimes exaggerated in pathological states as mania.
Kick down the barricades Listen what the kids say.
From time to time people change their minds But the Frock is here to stay.
I've seen it all from the bottom to the top Everywhere I go the kids wanna Frock.
Around the world or around the block Everywhere I go the kids wanna Frock.

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Tony   100 mW

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Post by Tony » May 19 2007 7:22am

Hi all, after my short experience withe the Puma thus far failure of the gears is way down on the list of my concerns. Yes, I don't jam the throttle on full at a stop on a steep hill- common sense. After examining the gears the very worst that may happen IMO is the small teeth would shred causing some debris into the case, not enough to seize the rotation of the motor. After riding around town the past weeks I feel the chances of being hit by a motorist or hitting a pot hole and crashing are much more likley to happen than the gear set letting go.

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dermot   100 W

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Post by dermot » May 20 2007 6:58am

NickF23 wrote:Hi Dermot

You might well be able to get a lot more out of your existing motor, either with a new controller or/and battery pack.

The fastest accelerating bike I've ridden on had a nominal 500 watt heinzemann motor with with a teamhybrid/evtech lipo pack. The owner (Richard( used to have the screen name Reb and post on the old forums sometimes). I beleive it had a 50 amp 4QD controller. Certainly had some very fierce torque.
I did consider pushing the Heinzmann to 48V with a different controller, but this is is my only bike and my main means of commuting (on average, I've driven around a thousand miles per year over the last 6 years or so - increased a bit with recent job changes).

I don't want to risk blowing up my only ride....

I could get a Puma spoked-up into a spare wheel, then get back operating quite quickly if I hit a snag, or try for a second, folding, bike which I'm now considering doing.

Any ideas when the front version of the Puma is coming out?

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knoxie   10 MW

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Post by knoxie » May 20 2007 10:50am


Yes its worth making another bike, I find that having 5 bikes is the safest bet :lol: I am not sure when the front ones will be coming over, Mark will tell me then I will tell the group.

I do 4,000 miles a year on one of my bikes so need to share that mileage around a little!! still its good to have a really reliable all weather machine which is what the Trek is, the others are fair weather rides, with the exception of the KMX which is great in the snow.




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