Rear Spokes Dilemma

[Morat]

I have a bit of a dilemma. The rear wheel on our Cannondale has just gone out of true for the first time. It's not far out just a couple of mm, but with 33stone on the bike I know it's only a matter of time before the dreaded PING so I'm looking for a rebuild.

The wheel is all DT Swiss. Tandem hub, rim, spokes.

My LBS has good wheelbuilders but doesn't specialise in tandems. The closest match in spokes they can offer are DT Swiss Competition which they say they use for national level downhill mountain bikers.
Should I just go ahead with those spokes and hope that a hand built wheel will be more durable? Does anyone have experience of using DT Competition for a tandem?

Thanks all
Morat

[Morat]

Don't worry, I won't hold anyone legally responsible

[marcusjb]

Something like the Alpine III would be more appropriate I personally think.  Comps are a pretty light spoke, I am surprised to see them used in DH wheels to be honest.

(I can't remember what we have on our tandem wheels - I think it is Alpine III).

Edit - DT Swiss themselves don't have the comp as a recommended spoke for DH, let alone tandems (whereas Apline III is recommended for tandem wheels):

http://www.dtswiss.com/Components/Spokes/DT-competition/DT-competition-sup-%C2%AE-sup-en

Further edit - we're on standard Alpines (but we run 32 hole wheels front and rear on the tandem due to Rohloff).  We're a light team at 120kg, so could probably get away with pretty much anything - but it is a touring tandem, so does carry some weight).

[Morat]

Having read around I'm very much inclined to agree. I think I'll get it trued this time and try to source some black Alpine 3 spokes on the right size (seems hard to measure spokes without removing them though).
Thanks!

[Ian H]

One of the advantages of Alpine III is the 13g elbow, which is a tight fit in most hub flanges.  Just that detail reduces spoke breakages due to fatigue by a goodly amount.

[Morat]

I went to a more local LBS to see if they'd true the wheel while I hunt out some of the correct spokes. Turns out there was a brokens spoke after all, but the VLBS reckon they can get hold of the correct spokes and will do a fix. I'll find out soon enough I guess. VLBS don't build wheels in house, but send out to a firm called Walkers*. I reckon they can put in a new spoke and true up the wheel to last us until we can get a rebuild organised.

In the meantime, the more I read into this, the happier I am I posted up here!

The DT 540 tandem hubs do have the larger holes in the flanges so I would imagine a smaller spoke/elbow wouldn't be such a good fit. Whether that looseness is something to be avoided I just don't know but it seems silly not to take advantage of the opportunity for added strength.

The wheels are 36H three cross at the moment. I'm a bit gutted that we broke the spoke in the first place, perhaps it's time to heed the warning and be more careful/lose some weight!

*has anyone heard of them?

[P Walsh]

Might be worth asking for a few spare spokes with any new wheel.

[The French Tandem]

The DT 540 tandem hubs do have the larger holes in the flanges so I would imagine a smaller spoke/elbow wouldn't be such a good fit. Whether that looseness is something to be avoided I just don't know but it seems silly not to take advantage of the opportunity for added strength.

As long as your spokes are properly tensioned, there won't be any looseness. A slightly larger hole is not normally a problem.

The wheels are 36H three cross at the moment. I'm a bit gutted that we broke the spoke in the first place, perhaps it's time to heed the warning and be more careful/lose some weight!

Some people will not agree with me, but I think 36 spokes are not enough for a 33 stones team. We are just slightly lighter than you are, and we used to break spokes on a very regular basis, until I built our current wheel: Velocity Dyad 48h 4 cross, Alpine 3 spokes. That was 15 000 km ago, and we never broke a single spoke since that moment.

[Morat]

The DT 540 tandem hubs do have the larger holes in the flanges so I would imagine a smaller spoke/elbow wouldn't be such a good fit. Whether that looseness is something to be avoided I just don't know but it seems silly not to take advantage of the opportunity for added strength.

As long as your spokes are properly tensioned, there won't be any looseness. A slightly larger hole is not normally a problem.

The wheels are 36H three cross at the moment. I'm a bit gutted that we broke the spoke in the first place, perhaps it's time to heed the warning and be more careful/lose some weight!

Some people will not agree with me, but I think 36 spokes are not enough for a 33 stones team. We are just slightly lighter than you are, and we used to break spokes on a very regular basis, until I built our current wheel: Velocity Dyad 48h 4 cross, Alpine 3 spokes. That was 15 000 km ago, and we never broke a single spoke since that moment.

I think you're probably right, the wheels have done about 1500 miles until now which isn't a huge distance. However, I didn't buy the bike and I don't think the captain is going to go all out with a new wheel at the first broken spoke so we'll get it fixed up and see. If that spoke was the first of many (as I fear) then we'll have to think again.

What hub did you use in your uberwheel?

Just as an idle thought but I'm wondering if it was coincidence that we broke our first spoke on the same ride that we faded the brakes for the first time. We'd done some very hard and quite sudden braking on that ride (in an attempt to avoid dragging the disks) and I suspect that the disk brake forces might have added to the torture.

[The French Tandem]

What hub did you use in your uberwheel?

White Industries Daisy hubs.  Still runs on the original bearings!

Just as an idle thought but I'm wondering if it was coincidence that we broke our first spoke on the same ride that we faded the brakes for the first time. We'd done some very hard and quite sudden braking on that ride (in an attempt to avoid dragging the disks) and I suspect that the disk brake forces might have added to the torture.

What I know for sure is that disk brakes always put more stress on the spokes than rim brakes. Is this enough to break an already weakened spoke? I don't know.

[321up]

We had two identical rear wheels built buy the same wheel builder, one with Alpine III spokes and the other with Sapium Strong's.  The overall weight was nearly identical.  We found the wheel with Sapium Strong spokes had less flex so we've used them on all our wheels since.  If your priority is comfort then you might prefer Alpine III.

[Morat]

As stoker, I've opted for comfort and bought Alpine III spokes!

It turns out that they're hard to get in black in the UK so I've bought them from Rose Bikes in Germany as recommended by vLBS.
http://www.rosebikes.co.uk/search/find/?q=DT%20Swiss%20Alpine%20III%20spoke

vLBS and LBS could only source boxes of 72 from the UK supplier. Rose bikes sell in 20s but the shipping cost as much as a box of spokes so I've bought two which should give us enough to replace 3 more spokes after this one before we're down to 36 at which point I suggest it's time to rebuild the wheel.

Strangely the spokes were 285mm on both sides, so it can't have a lot of dish.

[Biggsy]

Alpine III spokes are more fatigue resistant than Sapim Strong, due to triple butting versus single butting, so are less likely to break in the long run.

I've used them even on solo rear wheels.

[Peter]

OT  but Spokes Dilemma sounds as if he should be an African musician, specialising in Township Jive!

[marcusjb]

OT  but Spokes Dilemma sounds as if he should be an African musician, specialising in Township Jive!

 

Spokes Dilemma and The Brass Nipples?

[Morat]

After all that it turns out that the original spokes are Plain Gaugue. I would have spotted that if I was halfway competent :/
A rebuild is looking more likely.

[Morat]

The rebuilt wheel is on the tandem and has done ~50 miles as an acceptance trial. In the end I got some DT Swiss triple butted spokes from Rose Bikes for about £25 and the wheel was rebuilt by Walker Brothers thanks to VLBS who charged us £29 for the job which I found amazingly good value.
The wheel is absolutely bob-on true in both axes. We haven't really wound it up on the flat to see if it is noticeably more flexible yet, but it seems great so far.

I'm hoping that the increased fatige resistance of triple butted spokes will be what we need rather than the greater rigidity of plain gauge. Time will tell....