Stan’s Alpha 400 rims push the envelope of weight without concessions in strength — we can go lighter but not without hurting durability. Being deliberate about spoke count and spoke model, the same rims can be tuned for each rider. The first set is built with Sapim Race spokes, 24 front and 28 rear, which makes for a sturdy build.
The second set is built with Sapim D-Light spokes on the front and rear drive side with Sapim Laser rounding out the rear. This set is 20 spokes front and 24 spokes rear, which, as the scales show, makes for a 1453 gram alloy wheelset. Less stiff but a hoot in their own way.
Front wheel, 20 spokesRear wheel, 24 spokesWhite Industries T11 front wheel weightWhite Industries T11 rear wheel weight
When I started mountain biking all spokes were silver. It’s not as common these days but I think we should bring this look back. This is a set I did last month — they look great.
Hubs, rims and spokes readyHope Pro4 hubs to Stan's Arch MK3 rimsHope Pro4 hubsValve hole vision standard
This is a set of XC MTB wheels using DT Swiss 240S hubs and Light-Bicycle carbon rims. The rims are asymmetric, which allows for more balanced tension between sides of each wheel. The package is put together with Sapim D-Light spokes and Sapim aluminum nipples to keep weight low — only 1464 grams for the set. Tubeless-ready using Stan’s tape and valves. Very nice wheels.
Sapim D-Light spokesSapim aluminum nipplesDT Swiss 240S boost rear hubDT Swiss 240S boost front hubSetup tubeless with Stan's tape and valvesBuilt to tight tolerancesBuilt to tight tolerancesIn the mail
Pros measure the effective rim diameter (ERD) of every rim.
My tools are DIY, which is inexpensive. Here’s how I make them: take two black 310mm Sapim Leader spokes and cut off the elbow leaving a 300mm rod. Use bolt cutters or a hacksaw to get close, then creep up on 300mm exactly using a file or a grinder. Screw a silver nipple to each rod using a bit of Loctite so they never move. For my process I make sure the spoke penetrates the nipple until it’s flush with the bottom of the screwdriver flats — spokes stretch a little under tension so they’ll end up in a good place. That’s it. If you’re precision-minded, you can ensure nipple geometry isn’t a factor by making a new set of measuring rods any time you build with a new variety of nipple.
Usage is straightforward. Insert your measuring spokes into opposing spoke holes, counting them to make sure you’re not off by one. Pull the spokes tightly across a ruler. To make the process easier and more accurate, try raising the ruler with a shim so the spokes leave the rim closer to 90°. Use a ruler with 0.5mm resolution (such as this one) or eyeball to the same. For most builds the spokes will overlap on the ruler, in which case you deduct the overlap length from 600mm. If the spokes don’t overlap, add the gap length to 600mm. Perform at least two measurements 90° apart and average the results to get ERD.
Note: you don’t need 300mm spokes to make a tool but it makes the addition/subtraction less error-prone. Use what you have but adjust the arithmetic factor to the sum of the length of your rods. If by some trick you end up with 300mm and 299mm rods, carry on using 599mm in your calculations instead of 600mm.
Measuring rods and mounted rulerRod penetrationDifferent tools for each nippleUsing the rods and ruler
If you’re building with nipple washers, remember to increase spoke length to compensate. As an alternative, you can install nipple washers on your measuring spokes and build nipple washers right into your ERD. With asymmetric washers it’s helpful to give your measuring spokes a spin after pulling them taut just to make sure everything is seated properly. Overall this approach accounts for the end-to-end nipple/washer/rim fit and avoids errors from incorrect nominal measurements (a real thing).
Most spoke calculators will give you lengths to the tenth of a millimetre, which you’ll need to round to the nearest available length. Since measuring as above targets the bottom of the acceptable range, resist rounding down for low tension builds or on the low tension side of a wheel. In a future blog I’ll expand on the topic of rounding.
Sometimes newbies ask about cheap rims to try wheelbuilding, which isn’t the right way to think about starting. Rim quality sets the stage so inexpensive rims may serve to frustrate more than anything. If you’re apprehensive about wheelbuilding, and there isn’t any reason to be, stay away from ultralight rims and low spoke count rims. Stay away from ultralight spokes. Buy a quality rim with the attributes you want to ride and you’ll do fine.
This is another build using China-direct carbon rims. These are tubulars from Light-Bicycle, a brand featured on this blog a few times. They’re nice rims. The new infosheet from LB says special skills are required to build carbon rims but I can’t agree. If you’re smart enough to use a tensiometer, you can build carbon. I like nipple washers with carbon but otherwise my process is the same.
Light-Bicycle instructionsDT Swiss 350 hubs to Light-Bicycle tubular rimsPerfect tension balance frontPerfect tension balance front rear
A recent build using economical carbon rims from Light-Bicycle. I selected Sapim D-Light spokes and aluminum nipples to save weight without compromising durability. Came out great!
Light-Bicycle and DT SwissDT Swiss 350 front hubDT Swiss 350 rear hubLight-Bicycle carbon tubeless rims
White Industries T11 hubs mated to Stan’s Alpha 400 rims is a combination I’ve built (and ridden) in more than one incarnation. This set is put together with Sapim Laser spokes in the front and rear non-drive side, Sapim Race rounding out the rear. That puts total weight a hair over 1500 grams while remaining stiff enough for the rider. These wheels are setup tubeless with Stan’s tape and valves supporting Schwalbe Pro One tires in 700×28. A perfect combination top to bottom.
Excellent road tubeless wheelsFront wheel is 646 gramsRear wheel is 872 gramsTires measure 29mm actual on Alpha 400 rims
Thanks to Ric from Wheel Fanatyk for scanning a series of articles on wheels and wheelbuilding. They cover a lot of ground that will interest wheelbuilders new and old. Download in PDF.