Author Topic: Cracked rim Smart Pie 700c  (Read 4085 times)

Offline Thuktun

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Cracked rim Smart Pie 700c
« on: February 28, 2017, 05:36:52 PM »
Yay for St John's and their bad roads. Riding to work this morning fell into a monster pothole that wasn't there yesterday, cracked the rim on my Smart Pie 700c. You can see the crack next to the tape. There's a flat spot on the wheel causing a bumpy ride and the spoke is loose. If I keep riding it it'll probably tear the other spokes out and buckle the wheel while I'm flying along in traffic so I guess I'm off the road for a bit.

What are my options here? Do I have to get a rim from Golden Motor or will any double walled rim do? Do they even sell just rims?

Offline Pwd

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Re: Cracked rim Smart Pie 700c
« Reply #1 on: February 28, 2017, 09:11:15 PM »
Hello,

any double wall rim should work but you will need the same spoke count and probably new spokes/spoke nipples. Hopefully someone else can chime in about lacing a Smart Pie onto a new rim but here is a good page I came across:
http://bruceteakle.blogspot.ca/p/hub-motor-wheelbuilding-for-ebikes.html

Here is a link I found to a new GM rim:
http://www.goldenmotor.ca/products/Golden-Motor-700c-Rim.html

they have spokes too:
http://www.goldenmotor.ca/categories/Parts-and-Accessories/Spokes/
« Last Edit: February 28, 2017, 09:51:14 PM by pwd »

Offline Thuktun

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Re: Cracked rim Smart Pie 700c
« Reply #2 on: March 01, 2017, 08:42:28 PM »
I'll bring it to a bike store. I laced a wheel once. Never again lol. I was thinking of getting a rim locally because it's quicker but I don't think I'll even fix this just yet. I won a Magic Pie Edge in the Golden Motor Facebook contest that's just sitting in a box waiting for a bike. I'm going to spend my money on a mountain bike for that first. When I do fix the Smart Pie I'll probably make it into a mountain bike wheel instead. I'm planning to build a lwb recumbent this summer, I'll put it on there. Had enough of those skinny 700c wheels, nothing but trouble around here.

Offline Bikemad

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Re: Cracked rim Smart Pie 700c
« Reply #3 on: March 01, 2017, 11:49:55 PM »
Here are the details for the GM 700c rim:


You will need to find a rim locally with the same Effective Rim Diameter (ERD) if you intend to reuse the same spokes.
A non-GM 700c rim may have a different ERD, which would require different length spokes.

The standard GM 700c rim should be less prone to damage with a 29" x 2.4" tyre fitted (if there is suitable clearance within your frame):



I fitted a pair of 29" x 2.25" tyres to my 700c rims on my Felt QX to replace the standard 700-37c tyres:



The front tyre fitted fine:



But, the rear tyre was just too wide for the frame.  :(
I have since purchased a 29" x 2.1" tyre for the rear wheel, but have still not had chance to see if it will fit within the frame yet.  :-[

Check out this post for more information on spoke lengths and measuring the ERD.

I suggest that you apply some penetrating oil to each of the spoke threads in the meantime, as this should make it a lot easier to undo the nipples when you eventually decide to replace the rim.  ;)

Alan
 
« Last Edit: July 02, 2017, 06:36:23 PM by Bikemad »