Project lightweight 29" custom wheels

solitone

Hi everybody,

I'm solitone from Italy, and I'm new to this forum--I've just written a couple of posts.

I have a longish travel 29er steel hardtail, with a 120 mm Manitou Tower fork and an American Classical All Mountain 29 wheelset, equipped with Schwalbe Hans Dampf 2.35" and Nobby Nic 2.25" tyres. I find this combination ideal for all-mountain riding.

Now I'd like to add a second pair of lighter wheels that I'd use for some XC and marathon races I've planned. So the new wheels should be both lightweight and reliable. Considering my current wheels weigh 1770 teams, I believe 1600 g would a proper target.

I'm considering the following components:

- Rims: DT Swiss XR 400 29 (450 g, with eyelets), or Stan's Crest (380 g).
- Spokes: DT Swiss Revolution, with alloy nipples (305 g).
- Hubs: Rotaz (390 g), Bitex (420), or Superstar Components Tesla (510 g).

Regarding the rims, the lighter the better, however I wouldn't feel much confident with a too thin rim on a long marathon ride. I therefore tend to look at the DT XR 400, but I wonder how it will perform with tubeless-ready tyres. Besides, I weigh 67 kg (148 lbs), and perhaps the Crest wouldn't be too risky. But you know, 29er wheels are a bad beast!

As for the hubs, I read several good opinions about the Rotaz, and few bad reviews. Some good posts about the Bitex, on mtbr.com. I personally like the Tesla, but it's the heavier and I feel it'd be overkill for my intended use (good choice for trail riding, though).

So guys, what's your take on this? Any advice?

Thanks a lot!

supersonic

Crest would be no problem at your weight - the obvious choice. The spokes should be fine too - hubs: A2Z, DT240. Should be able to get sub 1500g easily.

solitone

DT 240 are great hubs, but I'm after some cheaper choice. My budget for these new wheels is 500 € (420 GBP).

As far as I know, Rotaz hubs should be (very?) similar to A2Z ones, shouldn't they?

solitone

supersonic wrote:

Crest would be no problem at your weight - the obvious choice.

Even on 29ers?

I often hear that sub-1700 g 29" wheels are pretty much weak. Is it true? This thought was the reason why I was targeting 1600 g, not 1500 g.

Too cautious? Please remember I'd use these wheels for marathons..

supersonic

67kg is below average weight. If you were 100kg and were riding all mountain I'd recommend something else.

they need to be as light as reasonably possible for the upgrade to be worthwhile.

njee20

Rotaz/A2Z are basically the same - Chin Huar. I'd go with those on Crests with Revs, decent wheelset.

bails87

I've got a wheelset comprising of:
DT Brass nipples
DT Revolution Spokes
Superstar Superfast front hub
Superstar Switch Evo rear hub
Stans Crest 29er Rims

They weigh 1590g. I use them for commuting, have bashed through a few potholes but not taken them 'proper' off roading, but I built them myself (first ever wheel build) and they're still straight and true.

solitone

Thanks all for your replies.

I'd rather have paired hubs on the front and rear. Besides, I prefer high flanges with equal diameter, so that I don't need too many different spoke lengths. Finally, I need a 15 mm front axle and a 12x142 mm rear axle.

I don't believe any Superstar Components hubset features all these characteristics but the Tesla, which is on the heavy side at 510 g thougj. For this reason, I was considering something else, like Rotaz or Bitex hubsets.

Rotaz is the lightest, however there are some mixed views about its reliability--e.g. http://forums.mtbr.com/wheels-tires/a2z ... 49202.html

Specifically, the rear hub has 6 pawls that are on the alloy hub body, not on a steel ring in the freehub body. Moreover, the aluminium axle seems to be pretty flexy and allows contact between the freehub and the hub shell (though I don't really know whether this should bother me, since I have an X12 thru-axle on the rear).

On the other hand, I have read some good opinions about Bitex hubs. For a marginal weight penalty (35 g), they seems to have a better pawl arrangement, and so I'm lending towards them.

BikeHubStore.com sells the MTB242 rear hub, which should be a Bitex hub, and it's also cheaper than the Rotaz:
http://www.bikehubstore.com/product-p/mtb252-10.htm

Has anybody got any experience with or heard about these hubs?

njee20

I've been using the A2Z hubs for a couple of years and haven't had any issues - could do with new bearings in the rear, and I did the front about 6 months ago, but I've generally been really impressed with them. Would have another set (or Rotaz etc).

solitone

I can't find Rotaz hubs for front 15 mm and rear 142x12 mm thru-axles.

Are they available in those axle configurations?

The only site selling Rotaz hubs I'm aware of is BikeHubStore.com. On Ebay I don't find much either. Do you know some other place I could look at?

njee20

No idea, assumed you'd looked into this first!

What about AM Classic then? Certainly appear to be Chin Haur hub shells. Not as cheap admittedly.

solitone

I thought I had seen them in that versions, but now I've double checked and it seems they aren't available. If so, I think I'll try the MTB252 and MYB162 hubs (made by Bitex) sold on Bike Hub Store.

I have American Classic hubs on my All Mountain 29 wheels, and I like them, but they are defenitely not cheap!

solitone

What's your take on alloy nipples on Crest rims? I read many people prefer brass nipples, as Crest don't have eyelets.

I'd prefer alloy for (i) weight and (ii) colour (they're available in red). But if there are serious reasons not to use alloy nipples on an alloy rim, like the Crest, I'll opt for brass.

Thanks!

njee20

Alloy nips weigh less, but are guaranteed to eventually corrode and seize. You weigh this up. The rim is irrelevant. I've personally got alu on my race wheels, but would use brass where I was less fussed about weight.

solitone

Ok, I see.

My point on rims was that, I suppose, a rim with steel eyelets should be less prone to seizing, as you wouldn't have an alloy-alloy interface.

solitone

OK, time for choosing spokes!

I was thinking of DT Revolution, but another option would be DT Super Comp.

For an overall weight penalty of less than 40 grams, perhaps I would benefit from stiffer and more precise wheels?

njee20

They will be stiffer, again it's a weight thing. I've had no real issues with Revolutions (on 26" wheels), and weigh very slightly more than you.

solitone

I've finally made up my mind. Here's my choice:

- Rims: Stan's NoTubes Crest 29;
- Hubs: MTB162/252, sold on BikeHubStore.com (contrary to what I wrote, they told me these hubs are not by Bitex--I've no idea as to who actually produces them, though);
- Spokes: Sapim D-Light (2.0-1.65-2.0 mm)--I'd rather have some additional stiffness in a 29" wheel;
- Nipples: Sapim Polyax alloy.

Now the usual questions ;-)

First, how long should be nipples, ideally? I believe 12 mm, but would 14 mm be too long? I ask as apparently it's easier to source 14 mm ones..

Then, typical spoke length issues.. I tried the DT calculator, but I don't have components at hand, so I used declared measures. But I am concerned about the ERD of the rims. Stan's website say Crest 29 have an 605 mm ERD. However, I've read that effective ERD would be at least 1 mm more. These are some measurements reported:

- 606.0-607.9 mm -- http://messageboard.notubes.com/viewtop ... f=2&t=2754
- 606.5 mm -- http://forums.mtbr.com/wheels-tires/sta ... 38341.html
- 606 mm -- Wheelbuilder.com verified

Has anybody got some experience with Crest 29 rims? May I trust Stan's figure?

Thanks!