What Size Spokes?

[dlovett]

This is my first attempt to build a wheel and I just wanted to ask you all a quick question about choosing spokes.

I want to build a pair of lightweight XC racing wheels for my Sonder Vir Fortis Fat bike, using DT Swiss Comp 1.8/2.0 Black spokes with DT Swiss Black, brass, 12mm, Pro Lock Nipples. I am using a pair of DT Swiss XR361 29” rims that are asymmetrical. With a pair of Love Mud Hurleyburly hubs

Love Mud Hurlyburly Front Hub
150 mm Wide, 15 mm axle
CNC’d aluminium hub shell 
6 bolt disc mount
Sealed cartridge bearings
CNC’d aluminium hub shell 
Weight: 192 g
Hole count: 32H
PCD: Left: 55.5 mm; Right: 55.5 mm
Flange to Centre: Left: 47 mm; Right: 59.5 mm

Love Mud Hurlyburly Rear Hub
197 mm Wide, 12 mm Axle
4 pawl with 36 tooth engagement
6 bolt disc mount
Sealed cartridge bearings
CNC’d aluminium hub shell 
CNC’d aluminium freehub
Interchangeable freehub body (Regular Shimano or SRAM XD)
Weight: 316 g
Hole count: 32H
PCD: Left: 55.5 mm; Right: 55.5 mm
Flange to Centre: Left: 62 mm; Right: 46 mm

I have used the DT Swiss calculator and for the Front Wheel (left) it has said 296.5 Accurate and 269 recommended.
for the Rear Wheel (right) it has said 296.3 Accurate and 269 recommended. These are easy to get.

However for the Front Wheel (right) it has said 298.7 Accurate and 299 recommended and Rear Wheel (right) it has said 299.2 Accurate and 299 recommended.

I cannot get the 299 spokes unless I have them cut down to size. Would you recommend doing this or would 298 or 300 be ok?

Many thanks for your help.

Duncan

[Bearlegged]

Get 298mm.

I'll always round down unless rounding up would mean an extra 0.4mm or less.

[redefined_cycles]

In that situation I'd normally go for 298 on the shorter side and 300 on the other... then tune out the extra/less length straight after having used the screwdriver tool thingy. Just go slowly and keep thinking whats going on at each stage and don't overdo if that helps...

[lune ranger]

298/300mm for the rear is my vote. Should build up fine if you take your time. A little bit less or a little bit more is fine in my experience.
Too short and they can be hard to lace. Too long and you get too much spoke sticking out into the rim which can be an issue with flat section rims

[FLV]

on those numbers I'd build with 298

But I always use a second calculator to check the numbers

https://www.wheelpro.co.uk/spokecalc/

[dlovett]

In addition to your replies, I ran another caLc and I spoke to my local wheel builder and Neil Sutton at Alpkit, both said go with 298 rather than 300. So I am now waiting for 40 296, 40 298 and 80 nippples plus valves, rim tape and a spoke key to arrive. Then the real fun begins, translating the Wheelpor book into practice.

Thanks alll for you advice

[Cheddar Man]

My advice is to do one of two things.

Option 1. Get an old wheel and hub, cut out the spokes, and have a complete practice run at it, all the calculations, lengths and lacing patterns etc are not quite what they seem from a book or a video. You will also be sure you have all the gubbins you need to actually make the wheels and get it nice and round.

Option 2. Give it up and send all the bits to a wheel builder, they will get it right first time and your wheels will be round and not mis-laced which you will only notice after you have finished.

[ScotRoutes]

My advice is to do one of two things.

Option 1. Get an old wheel and hub, cut out the spokes, and have a complete practice run at it, all the calculations, lengths and lacing patterns etc are not quite what they seem from a book or a video. You will also be sure you have all the gubbins you need to actually make the wheels and get it nice and round.

Option 2. Give it up and send all the bits to a wheel builder, they will get it right first time and your wheels will be round and not mis-laced which you will only notice after you have finished.

I self-taught from the Wheelpro book and never had any problems. All the wheels I've built are (to the best of my knowledge) still round and true.

[dlovett]

To be honest I want to do it myself as it’s a skill that would be handy to learn. It’s the only part of bike maintenance I don’t currently do. I have laced an old wheel up in practice and will take one apart and rebuild it as per the wheel lot book before I start on the new ones.

My advice is to do one of two things.

Option 1. Get an old wheel and hub, cut out the spokes, and have a complete practice run at it, all the calculations, lengths and lacing patterns etc are not quite what they seem from a book or a video. You will also be sure you have all the gubbins you need to actually make the wheels and get it nice and round.

Option 2. Give it up and send all the bits to a wheel builder, they will get it right first time and your wheels will be round and not mis-laced which you will only notice after you have finished.