SPOKE LENGTH

Joined
Dec 29, 2016
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Lanc's, England
I'm going to buy spokes for my wheels this weekend, and using different spoke calculators and get slightly different result with the same input data. I have a 4mm diff to centre of hub to spoke flange on both rear and front hub, so the left and right sides spoke length are slightly different.
I have 3 options.
  1. Get different length spokes.
  2. Make the wheel asymetric, does 4mm make a difference?
  3. Because the fork or frame is not built yet, I can compensate for the difference by adding some washers on one side to make the hub symmetric, so the spokes length get symmetric.
The calculated spoke length differ slightly from my supplier standard spoke length, up to about 3mm. I'm I correct in my understanding that a few mm up or down on spoke length make no different, it only slightly changes the hub position relative to the rim.
 
Joined
May 31, 2013
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South Benfleet, Essex, England, UK
Buy the appropriate spoke lengths for Left-Side right Side and use them accordingly.
Keep the piles separate and have a spare spoke or two of each length.
Is what I would do. Here we buy spokes in 2mm increments for £1.79 for 6 in Stainless @ 14Gauge.
Its not a big cost and it is a crucial element of the build.
 
Joined
Feb 7, 2008
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Nottinghamshire England
This is a good guide , no nonsense and cheap.

Musson Wheel building

The site also has recommended wheel spoke calculators and one of it's own.

What are these wheels going on ?

Are you saying both the non-drive wheel and the drive wheel will end up asymmetrical ?

It is usually only the drive wheel on normal bikes ?
 
Last edited:
Joined
Dec 29, 2016
Messages
357
Location
Lanc's, England
Hi Danny and Stormbird.

I'm building a e-bike and the front wheel will be a motor. That's why the front hub is asymmetric.
The rear hub is a Shimano SG-C6001-8CD, 8 gear internal.
I will purchase the e-bike bits from BSM Battery, I've chosen the Q100, same motor as Twinkle use.
They recommend 12 or 13 gauge spokes with a 2 cross pattern. I thought using the 13 gauge spokes both front and back.
They are selling spokes at BSM Batteries but the length they stock is 220mm, 230mm, 237mm and 240mm
I did use the spoke calculating site you recommended and the result was front 228.3 and 228.8mm and rear 233.6 and 234.2mm.
If i calculate the spooks symmetric I get front 228.3 and rear 233.8mm.
The 230mm might be ok for the front, but 237mm for the back?
The frame and fork will be home made so I have plenty of options to add washers or making the frame asymmetric to compensate for the 4mm diff, if I so wish.
 
Joined
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Messages
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Pegasus

Ok clearer now.

Because you are using pedals you need the front ring [ if only 1 ] or the centre ring [ if 3 ] to be directly in line with the sprocket on the 8 speed.

Apart from that you are free to build the rear wheel as you see fit ? as your frame can be adjusted accordingly ?

Good luck with the build...

regards Paul
 
Joined
Apr 15, 2013
Messages
2,054
Location
Washington state
purchased a hub motor only from Goldenmotors and now am trying to find the spoke calculator that will accept the hub diameter of 317.5mm. (diameter across the motor between spoke holes)
Hub motor is 25.4mm wide and rim is 546.1 mm diameter.
hoping I won't have to purchase new spokes. Thinking some spokes off 20" wheels my do the trick??
thinking 3x pattern
 
Joined
May 31, 2013
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3,983
Location
South Benfleet, Essex, England, UK
purchased a hub motor only from Goldenmotors and now am trying to find the spoke calculator that will accept the hub diameter of 317.5mm. (diameter across the motor between spoke holes)
Hub motor is 25.4mm wide and rim is 546.1 mm diameter.
hoping I won't have to purchase new spokes. Thinking some spokes off 20" wheels my do the trick??
thinking 3x pattern
Depends. I found that when I used 3 x pattern on my SA 90mm Hubs the exit angles of the spoke nipples at the rim was too great and difficult to get a spoke-key on.
On the N380 in 20" wheels they RECOMMEND a 1 x pattern.
HTH.
 
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need to do more research but found a site that tells me 236.64 mm is spoke length needed?
 
Joined
May 31, 2013
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3,983
Location
South Benfleet, Essex, England, UK
I used my usual site for this and it agrees.
However, I guessed that it was a 36 spoke rim (you didn't say) and 2mm spokes and I got this....
 
Joined
Apr 15, 2013
Messages
2,054
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Washington state
that looks like one of the sites I visited. finding it again, good luck, I have toooo many bike related bookmarks with spoke calculators.
Now just need to find a metric ruler to measure my used spokes.
 
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