I'm planning to replace the rim on this wheel as it has a hairline crack on one of the spoke holes. The spokes are 13g and in the past I've only been able to track down replacement spokes on a unicycle website. It was made in Belgium originally although I bought it in the UK. The previous owner must not have known how to remove the sprocket, as a lot of spokes were threaded into the hub the wrong way and I had to replace a lot of them.
Anyway. I don't know where to get a rim designed for 13g spokes. It seems like I either have to drill the new rim out to accommodate the larger spoke nipples, or I could replace all the spokes with 13g ones and use a more easily available rim.
I don't know - maybe 13g is more common than I think, I'm just going off my experience of trying to track down rims and spokes online.
I just wondered if anybody had any thoughts about which would be more sensible - drill the rim or go for new spokes, or ideas of where to track down a new rim that would fit straight off. The size is 700c and inner rim width 2.8cm outer - 2.1cm inner
- use 13G spokes in a rim drilled for 13G nipples - use 13G spokes in a rim drilled for 14G nipples, using 'converter' type nipples (13G thread, slim 14G size body) (*) - use butted 13/14G spokes (eg Sapim 'strong') and a 14G drilled rim - use 14G PG spokes and a 14G drilled rim
(*) the converter nipples will build OK but down the line if the nipples start to bind, they are as likely to round off as turn, being very thin-walled.
I would suggest that either of the last two options would be favourite; use spoke washers at the hub end, and build/stress-relieve wheel well. It is almost invariably the case that the spokes would have broken in the old wheel because the wheel was never very well built, the spokes didn't fit the hub well, and the wheel wasn't ever properly stress-relieved. You can do better than that.
A good rim to use might be a Ryde Sputnik. With this rim it is a good idea to 'tweak' the eyelets so that the nipples are not at an angle to the spokes.
As above, you don't need 13g spokes. In fact, you will get a better wheel with thinner spokes, because the stretch in thinner spokes means that the load is shared out between more spokes. (and your rim is less likely to crack) It looks like an internal geared and braked hub, so presumably the wheel isn't dished (much) so I would use 14/16g double butted spokes. Don't worry about the hub drillings …..the huge majority of hubs are drilled to accept 13g spokes, and the huge majority of wheels are built with 14g spokes; the "fit" of the spokes in the diameter of the hub drilling doesn't appear critical. The "fit" of the length of the spoke elbow in the thickness of the flange is more critical; as Brucey says you can use spoke washers in a situation where the flange is too thin.
Don't assume the spokes are the same length. The depth of the rim dictates the length of spoke in a swap like yours and that can vary quite a lot for any given size of wheel.
The older I get the more I’m inclined to act my shoe size, not my age.
Hi, yes I learned that lesson when I ordered the Sputnik rim I don't know many rims, but I knew I had a Sputnik on my touring bike and it was 700c, so ordered that one for the Dutch bike. I didn't really know about checking the ERD. But I do now, so when I switch over to the 13g spokes will take that into account. Thanks
Don't know your particular hub and spoke combo, if your spokes feel loose in the hub ,at the bend, you might want to consider washers at the hook end. Helps the spoke settle rather than letting the spoke fret in the hub and wear through the bend. Not usually a problem generally on wheels but can be on heavy load scenarios like Tandems.
IIRC the hub is a steelite one? The shell dimensions are almost identical to the current SAB3 hub which also has a steel shell. Because of the way this is put together the effective flange thickness is different on the left vs the right.
Using 607mm ERD for the rim, 82.7mm L and 65.5mm R flange diameters, 38mm left offset and 27mm right offset, x3 build gives spoke lengths of 286.5 L, 288.6mm R spoke lengths.
It varies with the spokes that you use but IME these hubs build up best when you use two spoke washers per spoke on the right flange and one on the left. The bracing angle on the RH spokes is pretty good but the wheel still has a fair amount of dish; this means that the LH spokes won't have a lot of tension in them (about 70% of the tension in the RH ones). I recommend that you use some threadlock on the LH nipples, else they will be in danger of unscrewing. If you just overtension the spokes both sides (easy to do with 13G spokes fitted), you may crack the rim.
As mentioned earlier, I recommend that you adjust the eyelets in a sputnik rim to avoid having a kink right next to the nipple. This is as (or more) important with 13G spokes vs with 14G ones; the 13G/14G converter nipples pretty much don't articulate in the eyelets at all, so any kinks will be worse than with 14G nipples.
BTW a set of 14G spokes for this wheel will weigh slightly over 260g. Using 13G spokes instead adds 100g to this figure. Using typical 14/16G DB spokes reduces the weight of the spokes to ~185g, i.e. they are about half the weight of 13G ones. If a 14G spoke extends elastically by ~0.4mm under tension then a 14/16G spoke will extend about 0.6mm and a 13G spoke by about 0.3mm.
As Colin mentioned wheels with DB spokes are very often more durable than those built with PG spokes. A good part of the reason is that the spokes are more elastic, thus they stretch more and this means that they are less likely to ever run slack even when the wheel is under load (which is what causes nipples to back out, and/or the elbows to move around and wear into the flanges). It also means that if the spokes settle a tiny bit at either end, they are less likely to go slack (which means that a spoke with half as much stretch in it is more than twice as likely to go slack). It also means that the loads are shared better between spokes, i.e. that any one spoke is less likely to see a high peak load. By contrast if you use 13G spokes they are far more likely to work loose in service, far more likely to see high speak loads, far more likely to crack the rim.
With any of these spokes the tension is limited by the rim, not the spokes, so you can build the wheel with any of these spokes and you won't (safely) get more tension into a 13G spoke than the others. I'd probably choose 14G PG spokes just because they are 'good enough', and for this sort of wheel the extra cost of DB spokes is perhaps not justified. If the wheel were more dished I'd probably use DB spokes on the left side.
I don't know many rims, but I knew I had a Sputnik on my touring bike and it was 700c, so ordered that one for the Dutch bike. I didn't really know about checking the ERD. But I do now, so when I switch over to the 13g spokes will take that into account. Thanks 