Author Topic: convert front Mp to rear  (Read 2816 times)

Offline DirtyGinge

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convert front Mp to rear
« on: December 07, 2010, 07:21:45 PM »
Anyone know if its possible to get hold of the side panel to convert a front MP to rear, I guess it would take axle rebuild  and respoking also...

:)
Infineon lyen edition 12 Fet
Goldenmotor Magic pie rear ....2000 Watt peak
oh yea.....Im too fat :)...but cute, oh yea, im cute

Offline MonkeyMagic

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Re: convert front Mp to rear
« Reply #1 on: December 08, 2010, 06:12:55 PM »
Hey why's that? You no likey the fronty?

Yes, axle because you would be completely off center, even running a single speed freewheel. Possibly forget about disc brake too. But a 140mm still might fit. I dunno about changing/modifying the axle... You wouldn't necessarily need to respoke it

My 2c ?

1. I own both front + rear matching size wheels. Both have been run at different times el solo. The front motor ALWAYS out performed the rear wheel.
2. Changing my rear wheel tyre is a BIATCH!! Haha especially if you have torque arms/plates like me. Mine are bolted on so it is about a 20 or so minute job if you rushed it, plus repositioning it... urgghhh
3. You can probably get away without it, but you will want (and recommend to have) a torque arm/plate on your rear wheel to save any axle spinout. Not many rear dropouts are a super tight fit so they can wear seating easier.
4. The GM battery (if you have that one) Anderson connector points to the front. Lol it's easier to connect
5. Change the front tyre, disconnect 2 plugs, undo 2 bolts, remove and change tyre slap it back on and your away... yay

After using both at once, and separately if I had to choose to ditch one it would be the rear wheel. Just too much weight in the rear.
I can see any arguments about gutters, potholes etc. with a front motor, but that all comes with watching where you are going hehe

Ok so I'm curious whyyyyyyyyy

:D


Offline DirtyGinge

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Re: convert front Mp to rear
« Reply #2 on: December 09, 2010, 10:33:51 AM »
Hi there

thanks for the reply......,.I recently came into a supply of 18650 lithium cells which have been built into a nice big battery, so battery power is no longer an issue, was thinking of getting an external 40A controller for more power, however, I would be concerned about the front forks taking the stress....they are currenlty suntour xct's

I have torque arms fitted, but just worried about the stress further up the forks....any thoughts on this ? or any recommendation for good mtb forks ?

hell, might just have to run 2 x MP instead

thanks for the help
Infineon lyen edition 12 Fet
Goldenmotor Magic pie rear ....2000 Watt peak
oh yea.....Im too fat :)...but cute, oh yea, im cute

Offline MonkeyMagic

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Re: convert front Mp to rear
« Reply #3 on: December 09, 2010, 01:25:06 PM »
ooooh

I say go 2, and external for both if you have the juice! I think you would be the first to the forums knowledge.

Hehe that thing would go mental :D

Offline DirtyGinge

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Re: convert front Mp to rear
« Reply #4 on: December 09, 2010, 09:45:22 PM »
yup, sounds like a plan :)

second battery design up and running......13 series 16 parralel 2.2 ah 3.7 volt 18650 cells running, divided in 2 packs connected by genuine anderson powerpoles on either side of the bike to balance weight

all I can say is that the consistant torque is realy cool.....17 mile journey from work, 6.5 amp hours resulted in only a 2 volt drop in the battery, which to me on an internal controller makes the biggest factor, voltage stays higher for longer...so id say its got to be time for a second Magic Pie :) ...many thanks for your feedback

Should anyone else decide to make their own battery, please please please be aware that lithium batteries can only be described as bombs waiting to go off.......they will overcharge quite happily by themselves, and 10 minutes is the difference between a stable in series battery, and a thermal runaway waiting to blow cell......professional systems have a battery management system to protect the cells, if you make your own large one, it probably will be to expensive...this unit can only ever be charged in the garden in a waterproof box :(, with a turnigy watt meter and constant supervision.....

in testing these cells to make sure that I only included cells that were "matched", I had at least 10 cells charge easily to 4.7  volts in a very short space of time, even though the rest in the series charged to 4.0 - 4.1....should I have included these cells without testing, probably in a very short space of time, my house would be burnt out...


It did make me think though, do goldenmotor test match the cells for battery packs......if the BMS cuts out at 4.2 for the first cell to hit it, there could be from my experience here a big difference in voltages in the other cells

one of these days, ill do an infomercial and record the whole story in pics for you guys, stealth cut outs, batteries and all:

gnight all
Infineon lyen edition 12 Fet
Goldenmotor Magic pie rear ....2000 Watt peak
oh yea.....Im too fat :)...but cute, oh yea, im cute