New member with some Magic Pie questions

[blompod]

Hi all I’m new here and looking for some advice, I want to put together an ebike using the Magic Pie 3, I figure if it’s being released to the public soon I should wait and get the 3. Its going to be my only transport for the next 4 years, so I want to get it in the 1000w configuration using the 48v battery. The bike I want to fit it to is an Electra Ticino 8D and make it a front hub, which brings me to my first question, what’s the pros and cons to front and rear hub drives. Now I’m not a total noob as I have a 500w front hub bike now and it’s great, only drawback I have found being front hub is in the wet going up hills or if I’m on the throttle and peddling hard the front wheel can spin, lose traction a bit which is a tad scary, losing the front end on any two wheeler, but as I said it was only in the wet sometimes. I’m sure firstly whacking it on the front end is a whole lot easier than the back with all the gears etc.

I also want the best range I can get, can you run two batteries and double your range? Or do you just have a spare battery with you and swap it over if you’re going for a long ride? I have a 20ah 36v on my 500w and with me helping it a lot pedalling I get about 35kms in range. Oh also do you think it’s wise to purchase a spare controller, just to have in case the first one sh!ts its self? Pros and cons of internal and external controllers? I hope Ive done this new member post thing right. Thank you and glad to be aboard 

[Andrew]

I would run a rear motor not just because of better traction but if you get a failure at speed and the rear motor locks up you are likley to save your face

You can run two batteries together in parallel to get extra range.  Parallel = Amp hours/ range,  Series= speed and acceleration


Probably a good idea to wait for the new 'MP3',  I hope the controllers are less limited compared to the last ones as these were a big let down in performance, maximum wattage 750w under load with a 48v/12ah GM Lithium batt pack. Golden Motor Canada has reported better wattage from the MP3 controller, but i'm not sure if if can buy replacement 'internal' controllers yet for the MP3

Andrew

Try messaging Golden Motor Canada aka 'Gary'  for more details

[blompod]

Is it more involved fitting a MP to the rear than to the front? with the cassette and derailleur etc?

[e-lmer]

Yes, and no. 

You have to be sure there is enough room between
the rear forks, and the cassette they supply is a 5
speed.

 The front wheel is easier to mount, but has some
special safety issues because of what happens
when the wheel falls off.

[blompod]

Yes I read 135mm for the back, what do you mean "they supply is a 5 speed"? and "safety issues when the wheel falls off" ?

[e-lmer]

My deurailer is a 6 speed, but the wheel comes with a 5 speed gear.

On the front fork accelerating and braking trend to loosen the nuts. 
If the rear wheel falls off, you can get hurt, but if the front goes you are guaranteed a world of pain. (personal experience.)

That is why there is so much talk of torque arms on this forum.

[blompod]

I know I just noticed these talk arms, I have a 500w front hub motor on my bike been using it for months put about 2500km on it so far. No torque arm fitted, now I’m a bit concerned, I will order one from eBay asap, trouble is it’s from the states and will take a while to arrive, I'll just keep an eye on my front axle nuts check they’re not loosening. I also read in extreme cases the drop out can fatigue and break without a torque arm and you lose the front wheel that way.

So the MP rear wheel kit comes with a 5 speed cassette? but the bike I want to fit it to comes standard with an 8 speed, I can just use the bikes gear set cant I if it has 135mm space between the drop outs? 

[Bikemad]

So the MP rear wheel kit comes with a 5 speed cassette? but the bike I want to fit it to comes standard with an 8 speed, I can just use the bikes gear set cant I if it has 135mm space between the drop outs?

Unfortunately, the cassette type gear clusters found on most modern bikes is not suitable for the Magic Pie which is designed for the older "thread-on" type of freewheel unit.
Check out this post to see the differences between freewheels and cassettes.

The freewheel unit is not usually supplied with the standard GM kit, but a 6 speed version can be purchased separately from the accessories section if you don't already have one.

The 7 Speed Shimano freewheel that I fitted to a MkI Pie needed an additional spacer washer on the axle to provide enough clearance between the gear cluster and the frame:


The same freewheel fitted on a MPIII did not require the additional spacer washer:



It should be possible to fit an 8 speed freewheel and an additional spacer washer to the MPIII without having to spread the frame too much.

Andrew posted a topic regarding a 7 Speed Freewheel with 11 tooth cog for Magic Pie.

Eric fitted a 9 speed freewheel which needed two spacer washers on an original MkI Pie.

Alan
 

[blompod]

thats great Alan thanks, good to know it can be done then

[Andrew]

you can pick up 6 or 7 speed shimano 'freewheels' on ebay cheap.  Make sure you get a freewheel tool as well, it will have to be a 'UG' fitting not a 'HG' fitting.   You will find that your 8 speed derailleur will still work fine, along with your gear shifter.   You may have to adjust the tiny screws on the back of your derailleur which just help move the chain slightly so cog and chain line up together for a smooth run.  This vdeo helped me the first time I did it..... http://www.youtube.com/watch?v=Q1I0P9MjVns&list=FLexCgFkBChKLHhKZiSw6H-w&index=21&feature=plpp_video   It's really quite easy, and to be honest you'll probably will only ever use the three smallest cogs due to the MP's power.

[e-lmer]

Thanks too.

I looked at the rear wheel and the reason I went with the
front was that I didn't look forward to changing the
deurailer and shifter.

 That and wanted better balance with batteries on the back.

[Andrew]

the bike can get very heavy on the rear with a pie and a battery at the back, so that is a minus point to a rear motor.  I've been lucky enough to get triangular packs made which can fit in the bike frame. this really does massively help with balance, also less top heavy and with better centre of gravity.