Dual Pies

[Andrew]

quote from GM website.....

Model: MagicPie Hub Motor
Programmable built-in controller
Accept versatile voltages: 24/36/48V
Regen braking and cruise control
60mm thin hub for common bike frames
Support disc-brake and 7-speed sproketPower Rating:250W-1000W
Weight: 7.5 Kgs (including internal controller)

[Bikemad]

I love the way they offer two different units, a standard 11-28T or the 11-34T "Mega Gear" option, yet the picture actually shows a 11-30T unit:

Hey also can you fit a 7 speed cluster on the wheel okay? I mean, should there not be any clearance issues, is there a maximum you can run on the pie?

For example, if somebody had a newer frame with 145mm dropouts, and used spacers past the cluster - would a 8spd+ fit?

MM, Erik managed to squeeze a nine speed freewheel onto a Magic Pie, and this was with one of the early Pies which had the off centred rim:


Alan
 

[Andrew]

worst case scenario.....   If the 11 tooth cog rubs or touches the axle frame in any way, I bet a 3mm torque washer can be squeezed on after the freewheel.

  p.s. about the DNP F.W  being 30-11..   I noticed that too!   but to be honest I wil only ever use the last 3 or 4 cogs.

[MonkeyMagic]

Cool geez I wouldn't have guessed 9spd, determination!
Can't say for sure, but doesn't look like there is a disc brake on there, but could be wrong. It's nicely squeezed on there

Actually Andrews cassette he found would suit me a treat.. Don't tell me you guys actually counted the teeth on the picture??! lol

[Bikemad]

Can't say for sure, but doesn't look like there is a disc brake on there, but could be wrong. It's nicely squeezed on there

Actually Andrews cassette freewheel he found would suit me a treat.. Don't tell me you guys actually counted the teeth on the picture??! lol

You're absolutely right, there's no disc brake fitted on Erik's dad's wheel, but that doesn't mean that it wouldn't fit.

The freewheel in the picture looked too small for 32T and too large for 28T so I had no option but to count the teeth.
Counting all the way up to 30 is really not that difficult, you can simply use your fingers once and each of your toes twice! 
Here's an alternative method you might like to try: Counting to 30 (You'll find it easier if you practice a few times).

Alan
 

[Andrew]

fingers crossed I will be able to tell you tomorrow that the 7 speed fits and that is with disc rotor that has about 3-4mm of washers pushing it wider out on the axle

[Andrew]

Anyway, back to the point. So in the opinion of those who have used and are using dual pies, is there no problem with turning? for example does the back of the bike want to keep going straight and can this be felt at all?

[MonkeyMagic]

hey lol that's what my brother kept saying before I bought the front wheel.
and "oh but what if the back wheel is spinning faster than the front" etc.

I actually feel 10x safer with the added weight, and I would say I have more overall traction too.

Before I got the front wheel, on a paved bike track going around a corner on a sunny day my front wheel lifted a bit, then with the rear wheel driving I speed wobbled and the bike went underneath me... Lol it was a pretty bad stack

Don't have to worry about that anymore... Actually I'm still struggling to find a downside apart from weight and the fear of damaging one of the wheels.

So turning is okay, but I don't recommend doing it in reverse. Then you will find some trouble

[Andrew]

well, just to keep you up to speed. I picked-up the DNP freewheel today. it looks like it has been heavily injected with grease/lubricant which is nice and should keep it quite quiet.  However, the freewheel remover tool I have is for a shimano splined cassette and not a screw on freewheel, there is only the slightest of difference between the two threads on the tool  .  So at the moment I have a freewheel remover that does not have a 14mm hole to fix over the axle, and a cassette remover that has a 14mm hole  but does not grip the freewheel properly to undo it

i've ordered the proper tool today but it probably won't arrive until the post starts again after christmas.

just for forum users future reference, if you have a shimano screw on freewheel you need a remover tool that is 'UG' compatible and not 'HG' - which is for a splined hub and cassette removal.

I think Shimano  UG is ultra glide ?
                      HG is hyper glide ?

[GM Canada]

Anyway, back to the point. So in the opinion of those who have used and are using dual pies, is there no problem with turning? for example does the back of the bike want to keep going straight and can this be felt at all?

I find the added weight balances it out more. My front battery does add to this as well. You can really feel the battery weight if your sitting still and swing handlebars back and forth but not the wheel. Its center of gravity is low. Sorta feels like a small motorcycle. Make sure you have good forks, mine are rock solid!

Gary


Gary

[GM Canada]

quote from GM website.....

Model: MagicPie Hub Motor
Programmable built-in controller
Accept versatile voltages: 24/36/48V
Regen braking and cruise control
60mm thin hub for common bike frames
Support disc-brake and 7-speed sproketPower Rating:250W-1000W
Weight: 7.5 Kgs (including internal controller)

I have only ever used 6 speed freewheels. I have heard some 7's are the same width as 6.

Gary

[Andrew]

comparing my DNP 7 speed f/w with the shimano 6 speed, there is at most 4mm difference. I hop and think I should be able to find that amount of space

[Andrew]

next question.  What would happen if I put a 1000w 48v HBS motor up front and not a MP. Would it not work due to different windings and speeds?

[Hardcore]

there has been reports of different speeds between mp and hbs 1kw at same voltage, it could be done, but one motor will work more then the other.