GoldenMotor.com Forum

General Category => Magic Pie & Smart Pie Discussions => Topic started by: Tamb on January 17, 2022, 02:46:52 AM

Title: Replacement spokes for Magic Pie 5 with 26 inch wheel
Post by: Tamb on January 17, 2022, 02:46:52 AM
Hello,
According to the earlier threads I've read
https://goldenmotor.com/SMF/index.php?topic=2480.0
https://goldenmotor.com/SMF/index.php?topic=6878.0

My wheel has spokes which are 110mm from the elbow to tip and 2.5mm thick.

I have two broken spokes that I'd like to replace, ideally without replacing the nipples

I wonder if these will fit the existing nipples
https://www.bicyclespokes.com.au/shop-1/p/8yzbf8ivibzo3vsxxfr5u05fp9w9at-fphak

These Sapim Strong 13/14 have been recommended, but I assume that they would need new nipples
https://www.bicyclespokes.com.au/shop-1/p/sapim-strong-14-gauge-j-bend

Thanks a lot for your advice
Title: Re: Replacement spokes for Magic Pie 5 with 26 inch wheel
Post by: Bikemad on January 17, 2022, 01:43:26 PM
Hi Tamb and(https://i.imgur.com/evDSMvT.png)to the forum.

The GM 26" MPII, MPIII, MP4 and MP5 wheels all use the same spokes:

(http://www.arhservices.co.uk/GoldenMotor/MPIIspoke.JPG)

The Sapim Leader 13G spokes should fit your original nipples, but the Sapim Strong 13/14G butted spokes would require the smaller 14G nipples to suit the smaller thread:

(http://www.arhservices.co.uk/GoldenMotor/Sapim%2013-14g%20butted%20strong%20spoke.jpg)

As you are only planning to replace two spokes, I suggest that you use the 13G (non-butted) thicker diameter spokes (https://www.bicyclespokes.com.au/shop-1/p/8yzbf8ivibzo3vsxxfr5u05fp9w9at-fphak) which are more comparable to your existing spokes and should use the same nipples.

However, if you were rebuilding the wheel using a standard 36 hole bicycle rim using all new spokes, I would recommend using the 13/14G butted spokes with 14G nipples.
Please note that fitting a different rim may require different length spokes if the rim depth is different.

Alan
 
Title: Re: Replacement spokes for Magic Pie 5 with 26 inch wheel
Post by: Tamb on February 08, 2022, 07:57:22 AM
Hi Tamb and(https://i.imgur.com/evDSMvT.png)to the forum.

The GM 26" MPII, MPIII, MP4 and MP5 wheels all use the same spokes:

(http://www.arhservices.co.uk/GoldenMotor/MPIIspoke.JPG)

The Sapim Leader 13G spokes should fit your original nipples, but the Sapim Strong 13/14G butted spokes would require the smaller 14G nipples to suit the smaller thread:

(http://www.arhservices.co.uk/GoldenMotor/Sapim%2013-14g%20butted%20strong%20spoke.jpg)

As you are only planning to replace two spokes, I suggest that you use the 13G (non-butted) thicker diameter spokes (https://www.bicyclespokes.com.au/shop-1/p/8yzbf8ivibzo3vsxxfr5u05fp9w9at-fphak) which are more comparable to your existing spokes and should use the same nipples.

However, if you were rebuilding the wheel using a standard 36 hole bicycle rim using all new spokes, I would recommend using the 13/14G butted spokes with 14G nipples.
Please note that fitting a different rim may require different length spokes if the rim depth is different.

Alan

Thanks a lot for your help. I bought the suggested spokes and fitted them easily enough.
I've since broken another spoke (only a couple of rides). Any ideas why they are breaking so frequently? I have a lot of spares now but still - would be good to know how to avoid it!
Title: Re: Replacement spokes for Magic Pie 5 with 26 inch wheel
Post by: Bikemad on February 08, 2022, 10:50:07 PM

If your spokes are all breaking on the elbow section like this:

(http://1.bp.blogspot.com/_gA93NEz9L84/R6YKyvuqJDI/AAAAAAAAA60/PBHnjHc387c/s1600/DSC_3492+%28Medium%29.JPG)

It's because the spokes are failing due to metal fatigue caused by the constant flexing of the elbow as the spokes are not correctly supported at the flange end.

I suggest you read the following posts to find out why this happens, and how to prevent it from happening again:

Why spokes break. (http://goldenmotor.com/SMF/index.php?topic=3187.msg19243;topicseen#msg19243)

The best way to prevent spokes from breaking. (http://goldenmotor.com/SMF/index.php?topic=3746.msg25508;topicseen#msg25508)

Alan