Triplet lacing 8:16 on 32h rim

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ericoschmitt
Posts: 5
Joined: Fri Apr 21, 2017 7:47 pm

by ericoschmitt

I'm thinking about building 8:16 on a DT Swiss R460 32h rims skipping 1 every 4 holes. There are those "Ultra Light Hubs" on bikehubstore at 190g. I'm 61kg.
My concern is the wheel getting 8 jumps for the spokeless section. I've read those G3 rims are actually not round before lacing.

And how do I calculate it? Just get the DS spokes as a 4x lacing lenght and radial x0 lenght on the NDS?

A local mechanic told me the NDS holes would get misaligned and some spokes might be longer than others unless the tension is very unequal. Makes no sense to me.

What about getting the front wheel built with half the spokes, radially (16) on a 32h rim?

Should I get a set of 32h hubs so if everything goes wrong I can relace it? They are some 35g heavier for the set though, and my goal in getting low spokes is to save weight anyway. Just dont wanna waste hubs/rims.

by Weenie


Mackers
Posts: 483
Joined: Wed Sep 05, 2007 2:02 pm

by Mackers

The front wheel will have all spokes laced to either left or right oriented spoke holes unless you come up with some kind of paired pattern.
Generally seems like a bad idea with such a low spoke count.

You can just use regular spoke length calculators for the rear , you're basically building a 32 spoke wheel, just leaving out half of the nds spokes.

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LouisN
Posts: 2326
Joined: Mon Feb 19, 2007 3:44 am
Location: Canada

by LouisN

There's a thread on this somewhere...
I built a rear wheel with a 32h Powertap Pro+ hub on a 24h 38mm Boyd Carbon rim, with straight gauge spokes on the NDS, and CX rays on the DS. Still going strong after 3 years+.
OTOH, the only hub I had some difficulty with tension loss is the BHS UL 190 hub. I won't use this hub again.

Louis :)

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bikerjulio
Posts: 1901
Joined: Fri Dec 11, 2009 10:38 pm
Location: Welland, Ontario

by bikerjulio

This sounds like a really bad idea on lightweight low profile alloy rims.
There's sometimes a buggy.
How many drivers does a buggy have?

One.

So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

http://www.youtube.com/watch?v=GekiIMh4ZkM

fiziksdrop180
Posts: 2
Joined: Tue May 09, 2017 6:02 pm

by fiziksdrop180

ericoschmitt, did you end up building this triplet wheel?

I was thinking about doing the same thing, except with a Kinlin XR-31T rim and the Bitex RAR12 rear triplet specific hub (the SL210 Bike Hub Store hub). I've built with this rim and hub (normal 24 hole) before with Sapim CX-Ray spokes. It built up easy and rides great. Unfortunately the NDS tensions are only ~45% of the DS (which isn't too unusual I guess, but a couple NDS spokes were so low they didn't register on the Park Tool tensiometer). For the triplet, I'd use Spaim CX-Sprints instead of CX-Rays to gain some stiffness (according to my calculations, the Sprint is 20% stiffer than the Ray).

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F45
Posts: 869
Joined: Wed Jun 08, 2011 6:08 am

by F45

May I ask why you are inflicting this on yourself? You can buy R460 in 24 holes!

You can get XR31T rims in 24 hole for the rear and 16 for the front. Then the number of holes in the hub will equal the number of holes in the rim. Parity! Amazing!

TheKaiser
Posts: 482
Joined: Thu Sep 05, 2013 3:29 pm

by TheKaiser

fiziksdrop180 wrote:ericoschmitt, did you end up building this triplet wheel?

I was thinking about doing the same thing, except with a Kinlin XR-31T rim and the Bitex RAR12 rear triplet specific hub (the SL210 Bike Hub Store hub). I've built with this rim and hub (normal 24 hole) before with Sapim CX-Ray spokes. It built up easy and rides great. Unfortunately the NDS tensions are only ~45% of the DS (which isn't too unusual I guess, but a couple NDS spokes were so low they didn't register on the Park Tool tensiometer). For the triplet, I'd use Spaim CX-Sprints instead of CX-Rays to gain some stiffness (according to my calculations, the Sprint is 20% stiffer than the Ray).


On the rim that you describe above, that you built up previously, are you saying that the NDS tensions were only 45% of the DS even with 2:1 lacing? That seems crazy low, given that the whole point of 2:1 is to equalize tension. I know the BHS triplet hubs are not optimized for triplet in terms of flange spacing, but still, that seems terrible.

TheKaiser
Posts: 482
Joined: Thu Sep 05, 2013 3:29 pm

by TheKaiser

F45 wrote:May I ask why you are inflicting this on yourself? You can buy R460 in 24 holes!

You can get XR31T rims in 24 hole for the rear and 16 for the front. Then the number of holes in the hub will equal the number of holes in the rim. Parity! Amazing!


That is a good idea, although wouldn't that create a problem with spoke/nip angle, or are the R460s not directionally drilled? With a 32h, he would at least have 2 properly drilled drive side spoke exit angles on either side of each non drive side. I'd probably still opt for the 24h and use some combination of a wee bit of diamond file work/polyax nips/internal nips to correct the alignment a bit if needed.

kulivontot
Posts: 1170
Joined: Sun May 16, 2010 7:28 pm

by kulivontot

I would assume leaving large segments of rim unsupported due to unused holes would result in some kind of stress that the rims were not intended for.
But I am not a mechanical engineer and campy and rolf prima would beg to differ.

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WinterRider
Posts: 337
Joined: Tue Feb 05, 2013 2:46 pm

by WinterRider

ericoschmitt wrote:I'm thinking about building 8:16 on a DT Swiss R460 32h rims skipping 1 every 4 holes. There are those "Ultra Light Hubs" on bikehubstore at 190g. I'm 61kg.
My concern is the wheel getting 8 jumps for the spokeless section. I've read those G3 rims are actually not round before lacing.

And how do I calculate it? Just get the DS spokes as a 4x lacing lenght and radial x0 lenght on the NDS?

A local mechanic told me the NDS holes would get misaligned and some spokes might be longer than others unless the tension is very unequal. Makes no sense to me.

What about getting the front wheel built with half the spokes, radially (16) on a 32h rim?

Should I get a set of 32h hubs so if everything goes wrong I can relace it? They are some 35g heavier for the set though, and my goal in getting low spokes is to save weight anyway. Just dont wanna waste hubs/rims.


Done this.. heads in front 16H (200 lb rider) 1x... that experiment with common 14G spokes. Pounded over RR tracks... potholes etc.. stayed fine and intact. Tension '25 Park'.. or 120 kgf.

The rear 24H finished 105/95 kgf with 1x NDS heads in. That one is still rolling.. on one I moved.

Given reasonable, sound building practice.. skipping the holes is a non issue..if.. one is not kept up at night fretting on marketing issues for nuisances that often occupy space here. Yes.. those nuisances mean something for wheels used near their limits. But in the practical world there hand wringing to market components that feed the builder. That is fine... final cost means nothing to many. But final cost does not determine how a wheel stands.

fiziksdrop180
Posts: 2
Joined: Tue May 09, 2017 6:02 pm

by fiziksdrop180

TheKaiser wrote:
fiziksdrop180 wrote:ericoschmitt, did you end up building this triplet wheel?

I was thinking about doing the same thing, except with a Kinlin XR-31T rim and the Bitex RAR12 rear triplet specific hub (the SL210 Bike Hub Store hub). I've built with this rim and hub (normal 24 hole) before with Sapim CX-Ray spokes. It built up easy and rides great. Unfortunately the NDS tensions are only ~45% of the DS (which isn't too unusual I guess, but a couple NDS spokes were so low they didn't register on the Park Tool tensiometer). For the triplet, I'd use Spaim CX-Sprints instead of CX-Rays to gain some stiffness (according to my calculations, the Sprint is 20% stiffer than the Ray).


On the rim that you describe above, that you built up previously, are you saying that the NDS tensions were only 45% of the DS even with 2:1 lacing? That seems crazy low, given that the whole point of 2:1 is to equalize tension. I know the BHS triplet hubs are not optimized for triplet in terms of flange spacing, but still, that seems terrible.



Nah, the 45% NDS tension was for a regular 24 spoke rear wheel with 2 cross both sides. So for the triplet I should get up to 90% with the Bitex hub. Having only 8 NDS spokes scares me though...that's less than one side of a 20 hole front and the bracing angle is less

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WinterRider
Posts: 337
Joined: Tue Feb 05, 2013 2:46 pm

by WinterRider

Nah, the 45% NDS tension was for a regular 24 spoke rear wheel with 2 cross both sides. So for the triplet I should get up to 90% with the Bitex hub. Having only 8 NDS spokes scares me though...that's less than one side of a 20 hole front and the bracing angle is less" writes fiziksdrop180

My Bitex is 32H hub 16-8 with 105/95 ratio 3x and 1x NDS skip one hole. Lasers .. started service at 190's wt and down some now.. straight as the day I mounted it. 270 Kinlin rim .. never felt a drop of regard for my safety w 3000 mi on it to date.

Did a 27H 18/9 on 18H rim... after a ride I de-tensioned one NDS radial to see that effect. Did rub albeit somewhat wider clearance for the pads than I regularly run. But even a broken spoke would not meant any problem.

Triplets just IMO eliminate the lazy left side spokes and put the remaining half to work ... bracing angle is more marketing angle than reality for the many that ride. And noted here recently Campy allows riders to 240 lb on G3's... those 14-7's with 3 pair spoking.

by Weenie


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