Author Topic: Dual Drive Diamond back  (Read 20180 times)

Offline Who42

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Dual Drive Diamond back
« on: September 04, 2011, 05:51:20 AM »
Dual Drive Diamond back :o

I thought I might try a lite Dual Drive and it was very successful it pulls well up hills and on the flat it dose about 30km/h  ;D
Its nice and lite at about 23kg , I tried a Dual Drive MagicPie before but found it a bit to heavy at over 33kgs and I had to run Dual 48v LiIon batteries as well to supply enough amps :(
This Dual Drive is a good compromise and I am very happy with the results :D

Bike Specs
Diamond back  Apex.
Alloy Frame.
18 speed Shimano Gears.
Front Suspension Falks.
26'' Double wall rims.
26'' x 1.75 Low friction tiers
Front Disk Brake.
Rear Clamp brakes.
Dual Drive 2 x Wheel Ink 350w BLDC Hub motors.
48v 12amp Golden Motor LiIon Battery.
2 x Golden Motor Cruize Controllers.
Front and Rear LED lights.
Cycle Computer / Speedo
« Last Edit: September 04, 2011, 06:31:15 PM by Who42 »
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Offline Thaialien

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Re: Dual Drive Diamond back
« Reply #1 on: September 23, 2011, 12:19:12 AM »
Hi Who43 and others

When you going to make dual drive MW 12 B on 48v and on tires 3.50 x 8''  M/c. and folding to sell 48v batt pack YOU WILL BE SUPRIZED ! WHAT FUN YOU CAN KEEP IN THE BOOT/TRUNK  ;D

But you need some 135mm frpnt forks  and a helmet ! and glasses ! {for the dust and insects) I have rwo of these on the back of a TRIKE!

John L
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Offline MonkeyMagic

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Re: Dual Drive Diamond back
« Reply #2 on: September 23, 2011, 12:36:49 PM »
When you going to make dual drive MW 12 B on 48v and on tires 3.50 x 8''  M/c.

John L

Probably never..... Who42 from what I understand, only builds quality ebikes :D

hehe

Offline Thaialien

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Re: Dual Drive Diamond back
« Reply #3 on: September 25, 2011, 03:58:27 AM »
Hi Monkeymagic and all
Just because the wheels are small the frame is not on adult bikes ....

Japanese have adult folding bikes with 4inch rollerblade type wheels ! and you are sitting nearly as high as standard bicycle !

Maybe these are suitable for adults too

http://www.goldenmotor.com/frame-unicycle.htm
 
« Last Edit: November 14, 2011, 04:40:09 PM by GM Moderator »
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Offline Leslie

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Re: Dual Drive Diamond back
« Reply #4 on: December 28, 2011, 05:16:32 PM »
IS that a mini motor running at 48v or have I missed a new model release Mini motor?????

48v doesnt work kindly with the Mini motors from memory.  Check your windiings insulators for heat damage if youre not sure and wish to continue..

When running the little brushed motors I have, on a 26" wheel @ 24v it worked good.  As soon as I went up to 26" wheel @36v it burnt out.  However the little brushed motors run for years on a 20" wheel @ 36v.  So the dual drive may saving much load as long as both motors are running when going up steep hills.



Keep us informed how the dual 48v goes please.  Because if this works you have made the Mini motor work reliably at 48v IMO.
« Last Edit: December 28, 2011, 05:24:46 PM by Les »

Bring it on

Offline Who42

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Re: Dual Drive Diamond back
« Reply #5 on: December 29, 2011, 03:18:48 AM »
So far so good both mini motors are working fine they acutely work surpassingly well together :o
I am aware that 48v might be to much so I have limited the maximum sustained current  ::)
So far I have had no over heating problems but do keep an eye on my cycle analyst to keep things under control :P
At  Maximum cruise speed of 30kl/h they are only putting out about 200w each at full short team power is around 700w each  :o
I like this set up its light , its very powerful when you need it and surpassingly fast  ???
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Offline Leslie

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Re: Dual Drive Diamond back
« Reply #6 on: December 29, 2011, 04:09:20 AM »
Yeah sounds like youve checked all the boxes.  The shorter windings on the Mini do have lower resistance so it will pull more current at the higher voltage.

Just wondering the if there would be much difference between the efficiencies of switching lossed via fet/software current control v resistive shunt control methods.

Using dual Mini motors-controllers would be good at reducing any voltage drop over the standard controller shunts but puts more load onto the low resistance of the pack, This senario looks sunny for you..

I saw Gary's CA measure up to 7 watts idle running expense with dual controllers over two days this adds up to 338 watts. As you know a 12ah 48v pack contains 600 watts.  I make sure I turn the bugger off and charge after a long ride..

I disconnected all the leds at one stage and got a reading of 1.2 watts, but my whole shebang turns on at one switch right now, call me lazy, but only having to replace a single switch,  both my led night lights and motor is running about 7 idle watts now with no LVC. If I leave my bike switched on by accident I have 750 watts to waste, In 4.4 days my pack's from full to flat.  

If not for your reading experience for someone else here MrWho.  I always need to mention these little watts that have caught a few people out that only use their bike over week ends.

I have seen the problem with LVC not working well at very low discharge rates failing to trigger ..   My ex BMS shuted down at 48v assuming my pack wont go much over 30 amps 2c before pouches start to give up the ghost, my voltage drops at my packs terminals to 49v on my heaviest loads, this is safe.  Buying the bigger AH is essential for a reliable BMS regime IMO on the performance configurations.  Testing your voltage sag is an easy way to test your cell's health.  I remember the old GM packs were rated well over my pouch Lifepo4's.

Maybe it is whether a the BMS engineer considers flat and dead part of the AH or the BMS shut down the end of a packs AH max discharge rating.  I think some of the designers look at the cells manufacture LV floor rather than the real world beating a cell endures, in order to give us every bit of juice we pay for.  A noble gesture that only gets us a little bit further up the road.

Lifepo4 pack that see's 3v as an honest LVC point is the sure good.  Because under or closer to the LV floor of the cell, you don't get much aH for your voltages as the on load sag increase over the ride.  If we need those extra few Km's IMO is worth adding a little more lithium in order to have your safest BMS voltage LVC regime, just a bit higher than the cell manufacture recommendation and absloutes.
« Last Edit: December 29, 2011, 04:30:42 AM by Les »

Bring it on