Magic Pie 3 too wide for frame?

GoldenMotor.com

CoolCruiser

New Member
Jun 15, 2012
173
0
0
Massachusetts
I'd like to use a Magic Pie 3 rear wheel but they are 135mm wide and the rear dropouts on my aluminium Felt cruiser frame are 125mm wide. Everything I read says you can't widen an aluminium frame. Are my only options a 100mm front drive MP3 hub or find a different bike frame? Does anyone make a good quality rear wheel hub that fits a 125mm wide frame?
 

Velodrome

Well-Known Member
May 27, 2011
2,387
271
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Phoenix-ish
The problem is not that your frame is too narrow. What IS too narrow is the thinking of the manufacturers of these hub motors. They aparrently have convinced themselves that the ONLY people that want a hub drive bike are mountain bike riders. I had a bit of a rant on the Golden Motors forum over a year ago that got no response RE: the total absence of motors for 110mm bikes . Both classic and modern beach cruisers are probably about 30% of the total bicycle market ( totally pulled that stat out my bum ) for e bike conversion. Email'd one of the top guys in China at G.M. Got a response to; and he seemed to have no clue people in America still ride beach cruisers. Obviously nothing has changed. I've searched a bit and cannot find a single rear drive hub motor in 110 or 120mm spacing. The ignorant and all too common response in threads similar to this that I've read on Endless Sphere and such is the; just use a different bike ( read mountain bike ) and make your life easier. Well I don't want a stinking mountain bike and I don't wanna crack the frame on my $500 Felt Torch either, using Sheldons antics, trying to stretch it. I want a product made to work with something OTHER than a damn mountain bike. Too bad nobody is interested in making me something I want to buy; and many many others too.
 
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Easy Rider

Santa Cruz Scooter Works
Jan 15, 2008
2,145
7
38
Nor*Cal
My last build was a little narrow but all I did was spread the rear part of the frame until the axle dropped in place. I do notice that when I'm on the smallest cog, the chain rubs on the frame.
 

paul

Well-Known Member
Dec 23, 2007
5,547
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Kalamazoo, MI
i had the same problem and did like easy rider and spread the frame a little by hand and dropped it in, i ended up putting another washer on so i could use the low gear, over 6,000 miles and no problems at all
 

CoolCruiser

New Member
Jun 15, 2012
173
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Massachusetts
i had the same problem and did like easy rider and spread the frame a little by hand and dropped it in, i ended up putting another washer on so i could use the low gear, over 6,000 miles and no problems at all
How much did you have to spread it, and was that your Trek Pure (aluminium)? Mine has to go from 125mm to 135mm or .39".
I think Easy Rider's bike is steel which has better tolerance to flexing.
 
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paul

Well-Known Member
Dec 23, 2007
5,547
44
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Kalamazoo, MI
I had to with the trek 3500 mountain bike which is aluminum don't remember on the pure if I had to or not. I just sat and stared at it when I first got the motor and it would not fit and said heck with it. I had seen other trek 3500's online with a magic pie on it so I decided I am going to make it fit and pulled open the frame in front of the drop outs and had a friend slip the wheel in.
I am not suggesting you do that but I was willing to take the chance and it is what I did and it worked out fine for me.
 

Easy Rider

Santa Cruz Scooter Works
Jan 15, 2008
2,145
7
38
Nor*Cal
i ended up putting another washer on so i could use the low gear, over 6,000 miles and no problems at all
Thanks Paul, I'm going to do that when i get back home from Tempe, Az. Did you use the special washer that came with the kit?
 

paul

Well-Known Member
Dec 23, 2007
5,547
44
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66
Kalamazoo, MI
ya the one that is round with the oblong hole. but a round one would do the same thing. worked great, i just did it about a month ago, up till then i could not use the smallest gear
 

BarelyAWake

New Member
Jul 21, 2009
7,194
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0
Maine
Mentioning the washers... ya might want to consider roughing up the contact side of them to help prevent torque induced movement - not a big deal but I couldn't tighten the axle nuts enough to prevent slippage before this lil mod (see mark, first pic) but after a mo' w/a dremel I've not had that problem since;