Back in bid'ness

Two builds happening this week.

1. HED Belgium C2s with Ultegra 6800 hubs. 32 hole, 2 cross, 12 mm brass nipples. Durable, moderate cost, 1700 grams. That steel rear axle and cassette body really keep that weight up. Those HED rims have the nicest finish on the market. Pacenti SL23s are nice; these are better.
2. Stan's Arch EX with White Industries MI-6 (front) and Eno rear. 32 hole, 3 cross, 12 mm brass nipples. No one makes prettier hubs than WI.

HED Belgium+ Measurements

I'll be upfront about my bias: I love HED Cycling. They're a Minnesota based company that was an early innovator in wheel aerodynamics. Just like Greg LeMond, who was another Minnesota based innovator in bicycle aerodynamics. You know... I was another Minnesota based innovator in bicycle aerodynamics. At the age of 16, in 1991, I purchased Profile aero bars and slapped them onto the 1991 Cannondale Crit bike (SC 300) I was riding because I'd read they would make me faster. For the guys I was riding with--handmade steel, lugged frames--it was sin compounded by sin. They taught me the norms of cycling (or at least tried to). The lessons didn't sink in until much later.

Back to HED. They are a great company, and not just for their technology, but for their people: whenever I call them with a question about ERD, or to ask when the hell the 24 hole Belgiums C2s were going to show up (2011) they always pleasantly and patiently answered my questions. Tip: use the phone to interact with people; emails are way easier to ignore.

I've been rocking out on HED rims since 2009, when I built up a set on 32 hole White Industries H2/H3 hubs. In the interim, I've built two more wheelsets on their rims. HED now has a lot more competition in wide clincher rim market, but their quality has always been better than everyone else.

Competition is good when it leads to innovation and/or lower prices for consumers. With HED's new rim it's an 'or' not an 'and': the MSRP of the HED Belgium+ is $149 versus $119 for the existing C2. That works out to 10 bucks for every extra millimeter of internal width. The C2 is 17.5 mm bead-to-bead and the new one--check your math--is 20.5 mm. Sweet!

Brake track width is just over 25 mm. There appears to be zero transition (no lip) from the rim nose to the brake track, meaning the brake track is slightly toroidal. Excellent.

The hubs show up mid week: Campy Record 32 hole.

Worth the extra 30 bucks over the C2? Or the extra 50 over a Pacenti? We'll see...

First impressions: wide carbon clinchers

Just short of 100 miles on the new wheelset. Impressions so far using the wheels on the cross rig, with 700 x 25 clinchers, 80 psi & 90 psi (front/rear), 11-28 cassette.

Stiffness: carbon rims have no issues here. These are very stiff, especially with CX-Ray spokes.

Ride: not bad considering the stiffness.

Braking: good! This was a surprise. I won't be riding these in the rain, or bombing sustained descents. Using DT Swiss yellow fronts and Gigantex cork rear.

Aerodynamics: they don't feel fast, but they're also not susceptible to crosswinds.

Looks: head turners thanks to the 12k cosmetic weave.

The test rig.

It's hard to capture the luster of the 12k weave. It does look sweet--take my word for it.

The brake track uses the 3k weave.

38 mm, U-shaped profile, Sapim spokes, DT Swiss brass nipples. Black everywhere.

Carbon everywhere!

And yet more carbon...

Head tube badge. Carl Strong is the man.

The relentless pursuit of insanity

If you happen to be a perfectionist, wheel building is not for you. You'll never get perfectly uniform spoke tension and perfect roundness, so the best you can hope for is close enough on both measures. Adding quantitative measurements can either improve your wheel building by providing additional feedback, or drive you to madness with the pursuit of perfect numbers. I use a tensiometer and that's been 90 percent positive. Today I build my first wheel with the aid of lateral and radial truing gauges from Morningstar tools. We'll see if this is a good thing.

I will say that the experience thus far has been good. The tools shipped quickly from California, and they included a handwritten note from the owner, Paul. That's awesome, right? Gauges now mounted to my TS-2, I'm diving in...

Update: first build--Powertap G3, 38 mm wide carbon clincher, Sapim CX-Ray spokes--is done. These gauges are very useful and well worth the $120. The accompanying instructions could be clearer, but soon enough you'll figure out the logic of the setup.

One trip around the dial equals 0.1" and each unit is 0.001".  The wheel I just completed indicates a tolerance of +/- 0.005". This thing is fucking brilliant. (I can't say the same about building with CX-Ray spokes. More about spokes in the subsequent posting.)

Update two: this setup may be too accurate. I can now detect flat spots on the rim that are due to manufacturing defects. The current rim has 3 and they're about 0.002". Doesn't sound like much, and it's probably not, but it's annoying knowing they are there.

Nerd alert: Rim measurements

I'm cleaning my room today. It's where I sleep; it's where I build wheels; and it's where I store wheels, rims, hubs, and spokes. I've got other work to do, but it's not as much fun as wheel building. So to procrastinate, I decided to measure the internal/external dimensions of the rims on hand.

Yoeleo U shaped 25 mm carbon clincher
25 mm external/18 mm internal

Yishun 23 mm carbon tubular
23 mm external

Gigantex/Equinox carbon tubular
20.5 mm external

Velocity A23 clincher
22.8 mm external/17.5 mm internal
(This is equivalent to the HED Belgian and H Plus Son Archetype. The Pacenti SL23 measures 18.5 mm internally.)

DT Swiss 450 (double eyelet)
19.5 mm external/14 mm internal

Flashpoint FP60 clincher
18.4 mm external/13.4 mm internal
Can you say pinch-flat? Can you say 125 psi limit?

Velocity Arrowhead
20.25 mm external/14.2 mm internal

Wide carbon clincher rims

Captain Ahab: Moby Dick
Me: wide carbon rims

The sin of omission is commonly practiced by purveyors of carbon bicycle goods. It manifests when describing carbon rims and wheels. Taller was the old trend; wider is the new trend. WIDE CARBON CLINCHER RIMS! They'll tell you 23 mm wide. The problem is that is the measurement at the brake track. The measurement that counts is the internal bead-to-bead dimension. That is the dimension that will change your tire's profile from a lightbulb to a rounder and wider profile. Once you get over 17 mm for the internal dimension, you can legitimately claim wide rim status.

I recently received a 25 mm wide U shaped carbon rim from a new supplier in China. I put the calipers on it and--holy shit--truth in advertising. Outer: 25 mm; inner: 18 mm. It is 38 mm in depth with a 12k cosmetic weave. The set is, of course, 20/24 hole. It even has a u-shaped profile, which should add some stability in cross winds.

This will be a Powertap G3 wheelset for my road bike.
Scheduled build: in two weeks.

Destro's cross wheels

This morning I finished a set of carbon tubulars that will be fitted to a friend's new cross bike. The rims are second generation Yishun carbon tubulars, which measure 23 mm and have a nice deep center channel for your sew-ups. Gluing and mounting tires on these rims is very easy.

I don't have a scale so I will take them at their word on 400 grams/rim. The weave is 3k with a matte finish. They are round, except for one or two high spots from the mould. This lack of roundness is a problem I've noticed on every carbon rim I have sourced from China. (By way of contrast, the Gigantex/Equinox rim I built up was round.) If an alloy rim arrives out of round, it is a mere annoyance. When the rim is carbon, it is a major headache and the wheel will never be radially true.

Details for Destro's wheels
Front uses a White Industries T-11 hub, black. 20 hole
Radial lacing, using 2.0 DT Swiss spokes, laced to DT Swiss brass nipples

Rear uses a White Industries T-11 hub, black, 24 hole, Shimano/SRAM
DS is 2-cross, using 2.0/1.8 Sapim Laser, laced to DT Swiss brass nipples
NDS is 0-cross, *elbows out*, using 2.0 DT Swiss spokes, laced to DT Swiss brass nipples.

Notes

• I went with elbows out/radial for the rear NDS to increase lateral stiffness. I learned the hard way that not every hub is tolerant of this spoking pattern. Advice: make sure that hub is forged, not machined.
• I went with straight gauge on the NDS for the same reason as above. Now that Shimano/SRAM has gone to 11 speed, the DS flange has moved inboard with the effect being a drop in lateral stiffness. This can be compensated for with lacing, spoke diameter, and rim choice.
• The plus side for all manufacturers moving to 11 speed is that cassette bodies can now be swapped without redishing the wheel. To complete Destro's wheelset I had to swap Campy for Shimano. Took 10 minutes. That White Industries stuff is really nice.

Update: these are lighter than Mateo's cross wheels. In yo' face, Zartan!

Carbon rims and radial trueness

Lateral trueness is easy; radial trueness is hard. I'm always looking for better tools, and this morning I was researching Morningstar tools. They offer a dial-based truing gauge that will fit to a Park TS-2. Slowtwitch was the first review that popped up. Buried within an article on wheel building is a point about the difference between carbon and aluminum rims:

This is also the point where carbon and aluminum wheels differ. Carbon rims are much stiffer than aluminum. Put simply, the amount that you can radially manipulate a carbon rim is MUCH less than aluminum. As such, when adjusting radial trueness, you need to adjust many more spokes. Think of it as shifting the entire rim up or down – rather than bending a part of that rim to be more straight. Instead of adjusting 4 spokes, I might adjust 8 or 10. This also brings up the point that carbon wheels rely much more on roundness of the rim itself for a straight wheel; an imperfect rim cannot be manipulated very much (unlike aluminum). 

This is why cheap carbon rims are a really bad idea. There are plenty of other reasons why cheap carbon is a bad idea--labor conditions in those Chinese factories, for starters. Next up would be a total lack of warranty coverage for manufacturing defects.

Want a legit rim and customer service? See Brandon at the Bike Hub Store. Always great service and they're the only consumer source of Gigantex rims that I've found:

http://www.bikehubstore.com/category-s/124.htm

Getting back on that horse

It is almost July, and that means cross season is almost upon us. That means taking a break from riding all the wheels I've been building, and returning to the truing stand. What have I been riding? On the road bike, a lovely Pacenti SL23 wheelset with a 20 hole White Industries H2 on the front, and a 24 hole Powertap SL (with G3 internals) on the rear. These are shod with 700 x 25 mm Contis. Life below 90 psi is splendid.

Ongoing impressions of the Pacenti:

• They work very well with standard size road brake pads, exhibiting none of the pulsing I was experiencing with V-brakes. I suspect this has something to do with the length of the pad.
• Mounting tires is a real challenge. I suspect this is because of the tubeless rim design. Once I get a frame with the proper clearance, these will be an excellent candidate for the 28 mm Hutchinsons.
• My initial concern about the low spoke count was unfounded. These rims are plenty stiff for someone who goes 175.

What I am working on today:

• Relacing a rear 24 hole White Industries T-11 (Campy) onto a 50 mm Yishun carbon tubular. This will be straight gauge spokes in 2x (drive), 0x (non drive) pattern. This will be my rear wheel for cross.
• Relacing a rear 24 hole White Industries T-11 (Shimano) onto a 50 mm Yishun carbon tubular. This will be the same pattern as the above wheel. 
• Lacing a front 20 hole White Industries T-11 onto a 50 mm Yishun carbon tubular. This will be 0x with straight gauge spokes. This will be my front wheel for cross.

I'll go into the relacing in a separate post.

Here's the assembly line for today:

• T-11 hub--titanium cassette body--no gouging, unlike Chris King.
• 12mm brass nipples drying out after soaking overnight in triflow. Lube those nipples when building with carbon!
• Spokes and the all important spoke ruler.
• Lastly, my trusty and calibrated Park Tool TS-2 stand.

Updates to follow!

Mickie's Front Wheel

Currently building up a set for my friend Mickie. This will be her do-everything wheelset. Criteria: light, durable, comfortable and pretty. We chose navy blue Chris King R45 hubs in 24 and 28 drillings, with 2x Sapim Race spokes, 12mm brass nipples, and Pacenti SL23 rims.

The set is half way complete. This morning I finished the front, which I find more challenging than the rear.

The workspace: stand, Spotify, coffee mug, and spoke ruler. The pieces of tape on the stand are used to mark the rim in quarter sections, which aids in spoke tensioning.

One of the best.

Vital equipment: spoke tensiometer, spoke wrench, and tension chart. Wheel building is like a basketball game: the final minutes of the game can occupy a third of your time. This wheel didn't foul. Thankfully.

Pacenti rear Dura Ace 9000 wheel is done!

I managed to stretch this project out over 10 days. Test ride this afternoon. This wheel goes on my better half's pit bike. The DA hub is nice, but for the money, White Industries and Chris Kings are better. The verdict is still out on the rim. I've been riding the front Pacenti/DA wheel for 3 weeks. There was some initial pulsing when braking, but that seems to be going away.

The weight of the set should be around 1500 grams. Not bad for about $600 invested.

I can build wheels cheaper and lighter, but not better. These hubs should last 5 years of racing or 10 years of riding.

Ride report to follow....

Pacenti SL23 first impressions

Updated August 18

My new Dura Ace 9000 hubs arrived last week after what seemed like an eternity. The hubs, which are in 24/28 hole drilling, are pleasing to look at and are respectably light. Like anything with the Dura Ace name they'll last forever. The 7800 hubs Mateo raced on for three season still had intact grease and seals. Wizardry.

What the Dura Ace hubs are not is a good value. At the moment they are priced similarly to Chris King R45s and way out front of White Industries. Those are all equally good options, and will all be in service 5-10 years from now.

For this build I used the Pacenti SL23 rim. This was my first build on the rim and my impression is very good. The height of the brake track appears to be fairly generous. The rim is slightly taller and rounder than the comparable HED Belgium C2. The finish is flawless. And there were no metal burrs remaining in the rim from production. Most importantly: the rim is approximately 1mm wider than the HED, Velocity A23, or the H Plus Son Archetype. Added bonus: it is lighter than all those other options.

So how does it ride? Very nicely. The rim has a pleasing lateral stiffness, especially when combined with the 2x lacing.

Only potential downside: when I was truing the wheel I watched the stand's feeler gauge take off a sliver of metal from the brake track. Not sure if this happens with other rims, or whether this is a softer alloy. Kinda freaked me out.

Update: this is a great rim and unless the HED Belgian Plus (~$150 and non existent) knocks my socks off, this rim ($98 and available everywhere in multiple drillings) will be my go-to for future builds.

• The brake pulsing I experienced seems to happen only with long v-brake cartridges. Braking with standard road pads is smooth.
• There's no problem with pitting on the braking surface. I examined my pads after 500 miles of racing and city riding and there's no more embedded metal than one would expect. In fact, there was almost none.
• The only caution when building on these rims seems to be a tendency for the nipples to bind/stick during tensioning. These require more spoke alignment and stress relief than other rims. Again, I recommend these rims without reservation. They're the best combination of weight, value, and quality.

Spring Cleaning

I have always found that the best time to clean is when there's something else you should be doing, but don't want to. Like income tax returns. Compared to doing those, cleaning out the stash of bike parts is a joy.

I needed to dispose of two aluminum rims and a carbon fork. This task was made less desirable by the fact that I didn't simply want to leave these items on the curb--they were structurally unsound--so modifications were required.

The first to fall victim to the hacksaw blade was a 2006 Cannondale Premium+ full carbon fork. This fork was top-of-the-line back in its day, even featuring carbon dropouts. It was and still is ridiculously light. The problem is it was mounted to a bike that hit the back end of a Buick at 20 mph. Carbon is tough, but carbon also cracks. I didn't want some hipster douche salvaging this fork so I sawed it at the crown.

Wow. New respect for Cannondale carbon forks!

By comparison, here's the top of the steerer tube.

Next to fall victim to the hacksaw: a DT Swiss RR 1.1 rim. This rim is the Swiss interpretation of the venerable Mavic Open Pro rim. I believe the Swiss version is lighter and cheaper. Anyway, the rim in question was part of the rear wheel on my track bike. I just rebuilt the wheel when it took a 2" roofing nail in the tire. The nail punctured the rim bridge and then exited the rim's sidewall. The damage was impressive. I also rode it for another 12 months before replacing it with an H Plus Son Archetype.

Here's the DT Swiss next to a HED Ardennes rim.

The final victim was the most painful for me: a 24 hole HED Ardennes Scandium rim. HED rims are sold to the public under the name Belgian. These are regular 6000 series aluminum. HED saves the good and expensive stuff for their pre-built wheels. This rim was a Scandium version, which like the Higgs-Boson particle and unicorns, was just too good to be true. And it was, because I ended up destroying the rim during wheel building. Lesson: Scandium is lighter than 6000 series aluminum, but not necessarily as strong.

I cut apart both rims and here's the result.

The HED (left) is significantly wider. The DT Swiss rim (right) is significantly overbuilt.

Coming up: Pancetti SL23 rims laced to Dura Ace 9000 24/28 hole hubs. Hotness!

Carbon Toe-in

If I'm going to Hell, my punishment will be listening to improperly maintained, noisy bikes for eternity. Breaking in this carbon wheelset was a scared-straight visit to Hell: no matter what I did, I couldn't silence the squealing brakes. I sanded the brake pads (they build up a glaze), I meticulously cleaned the brake track with alcohol and acetone, and I even tried riding the brakes thinking it was only a matter of breaking-in the new rim's brake track. Nothing. The brakes were screeching loud enough to make neighborhood dogs howl. I concluded: this is the difference between a $200 Chinese carbon rim and a $800 Enve or Zipp rim.

As I was about to throw down some mad cash on different brake pads--a last attempt before writing off the wheelset--I researched the squealing carbon rim problem. There are three prevailing opinions: 1) it's a problem with cheaper rims; 2) it's  problem with certain rim/pad combinations; and 3) it's a problem related to improper pad toe-in. I had assumed #1 and #2, but hadn't considered #3.

So I toed in my yellow Swiss Stop pads on my road bike. Now my braking is quiet.

Who knew? From cross racing I was familiar with the cursed cantilever tendencies to howl unless toed-in. I never thought the same technique would work for a road bike with carbon rims. Lesson learned.

Only the finest brake pads that 60 bucks can buy.

That's some aggressive toe-in, son.

Carbon rims!

Question: Why does it cost 90 bucks to ship these things from China?
Answer: Because Vivian puts them on an airplane so they get here in 8 days.

My order of carbon rims has arrived:

• 1 set of 20/24 hole 50mm carbon tubulars
• 1 set of 20/24 hole 50mm carbon clinchers

I measured the ERD of the clinchers last night and they were within 1mm of factory claims. I've seen more variation on aluminum rims, FYI.

This batch of rims looks a little higher quality than the ones I ordered a year ago. Those were a unidirectional finish, and had the unlikely claim of being able to tolerate 250 Kgf spoke tension. Something may have been lost in translation.

This new batch is matte finish 3k carbon weave and carries a more realistic claim of 180 Kgf spoke tension before failure. This set is also lighter than the originals. The claim of 400 grams seems conservative.

I have ordered the spokes for the carbon clinchers/Chris King setup. That'll get laced and built this weekend. I hope.

Something to look at until those are together....

A harder, higher friction treatment for the brake track. Braking during cross season was sufficient. Not sure I'd bomb an Alpine descent on them.

The rentless pursuit of even spoke tension

Last night I finished off the dynamo wheel I have been building for my dad since his last birthday in August 2012. This wheel, like most I build, has a unique story. The rims (Velocity A23, 36 hole) were originally procured for a friend who was attempting her own build. Once she realized 26 inchers were needed, the 700c Velocity rims reverted to me. Building a super sweet dynamo wheel for my dad seemed like a great birthday present.

Several month, and several other wheel builds later, I am in the home stretch for this project. As I was in no particular hurry to finish this one, I decided to get it as technically perfect as I could. So I:

• Constructed my own spoke tension map. The Park Tool one doesn't work with my new tensiometer.
• Soaked the brass nipples overnight in Triflow. The point of doing this is to minimize the potential for spoke wind-up due to friction on the spoke threads, and friction between the nipple's shoulder and the rim.
• Used my new Wheel Fanatyk tensiometer. It was much easier to use than my old Park Tool tensiometer and much more accurate.

The result.

Red graph line indicates the right side spokes; blue is left; and gray is the average of both sides. This wheel is straight and true.

No too shabby. The average spoke tension varies +/- 1.5%. This 36 spoke wheel should last a lifetime even under my 200+ lb dad.

Now I can move onto other more exotic, low spoke count projects!

Classy

I love you UPS man.

I will be matching these with 50mm carbon clincher rims. These are the first CK hubs I have built with.

I excite!

- Borat

MY CLINCHER TIRES ARE RATED UP TO 180 PSI BUT I NOTICED ON YOUR WEBSITE THAT YOU RECOMMEND A MAXIMUM INFLATION OF ONLY 120 PSI (8 BARS), CAN I STILL PUT IN 180 PSI?

We use lightweight road clincher rims. We recommend not exceeding 120 psi (8 bars) even if the tires have a higher rating. Your risk of tire puncture, tire coming off the rim or rim damage is increased significantly by inflating to extreme pressures over 120psi (8 bars).

That question and answer is from the American Classic website. I was on it earlier today researching a new 29er rim they're offering to consumers. Looks promising: 380 grams, 25mm wide, and a 600mm ERD--all for 99 bucks.

No one preaches like the converted. I too was once addicted to high tire pressure. I thought   that the higher pressure meant a smaller contact patch and thus less road resistance. So I endured years of sore wrists and subpar braking and handling all in the pursuit of straight line speed. I used to buy Vredestein TriComp clinchers because they advertised a maximum inflation of 175 psi. I spat on the ground whenever anyone mentioned Michelins, as their max inflation was only 116 psi. Also, the skinnier the tire, the better. I was running nothing wider than a 700 x 23. I would use 20s if I could find them.

Once or twice a person tried to get through to me by forwarding an article about how lower pressures could actually offer lower rolling resistance. Whatever. What the hell does Sheldon Brown know? I was riding about 200+ miles per week (all commuting) so I wasn't about to test an idea that sounded illogical and that might add minutes to my commute by slowing me down.

But with age comes wisdom, sore joints, and product innovation. In 2007, HED released its Ardennes wheelset with the C2 rim profile. I paid attention because they're from Minnesota (as am I) and as a student of cycling tech history, I knew HED's reputation for pioneering ideas that were taken up by other manufacturers. The original tri-spoke was a HED design.

The C2 promised a tubular like experience by virtue of its wider rim bed, which changed the shape of the tire contact patch. Nothing over 100 psi was recommended, and nothing narrower than a 700 x 23. I guess I was ready to hear the message this time about tire pressure.

I ordered some rims once they became available and paired them with some White Industries hubs. Ever since, I haven't ridden over 100 psi on any clincher wheelset. I out roll, out handle, and out brake all the other fools who cling to their 19mm wide rims and 130 psi ways.

Mateo's Powertap

I'm not an impulse buyer, but a 24 hole Powertap for under 200 bucks was a bargain I couldn't resist. Hub acquired, the next question was what rim to use. The 24 hole drilling limited options and applications.

The Beast. It is laced 2x on both sides using Sapim Race spokes (2.0/1.8mm)

Possibilities (ranked $$$ to $)

- 50mm Carbon clincher (520 grams)

- 50mm Carbon tubular (400 grams)

- HED C2 tubular or clincher (439/478 grams)

- Velocity Chukker (664 grams)

- Velocity A23 (450 grams)

- H Plus Son Archetype (~460 grams)

Note: these rims are all 23mm or wider.

I settled on the A23 which was available in 24 hole and is a good combination of weight/cost. The only downside is the rim's 601mm ERD; it is a shallow rim, so it is not as tolerant of high spoke tensions. It is this characteristic that is significant with Powertaps.

Velocity A23. Made in the USA!

There are two knocks on Powertap hubs:

1. they're bricks. The one I am using is about 430 grams. Compare that to a White Industries T11 at 260 grams. It would be a significant weight penalty to carry in a race, unless paired to a stupid light rim, or mounted on a very light bike.
2. their geometry is compromised. The Powertaps have a large hub shell because it is stuffed with electronics. The transmitter electronics are stuck on the outside of the NDS flange. The effect is that the NDS flange moves towards the center of the hub, significantly affecting wheel stiffness on the NDS side. (Google Powertap spoke detensioning and you'll get lots of hits.)

For #2 compare the Powertap's center to flange measurements with the run-of-the-mill Dura Ace 7850 (in parenthesis): DS center to flange 17.4 (21.1); NDS center to flange  31.7 (36.9).* The closer the flanges move to the center of the wheel, the less laterally stiff a wheel becomes. This becomes especially relevant when using a box section or low profile rim which will be less stiff laterally and radially.

Given the special hub and rim properties, extra care had to be taken when building this wheel. I deburred the spoke holes on the rim. (If the drilling wasn't clean, the leftover material can cause spoke wind-up.) I used 14mm brass nipples (more tolerant of spoke tension, less friction against the aluminum rim, and more supportive of the spoke). Lastly, I made damn sure there was little variance in spoke tension. The tensiometer got a lot of use. This was a slow build process.

Continental GP4000s. The finest clincher out there. I will fight anyone who suggests otherwise.

The wheel is a gem. I rode it for several weeks before turning it over to Mateo. It was plenty stiff radially and laterally. There was zero brake rub, even when mounted to my v-brake equipped cross bike. The spoke tension, with a tire mounted and inflated to 100 psi, is: 100 Kgf on the driveside and 47 Kgf on the non driveside. That might seem low, but the tire is a 700 x 25 Conti GP4000s mounted to a soft, low spoke count rim. I am probably losing 10 percent or more spoke tension due to the compressive force of the tire/tube on the rim.

* The venerable DT Swiss 240 is has a DS spacing of 17 and 33.2.

CX wheelset

Due to slow progress on current wheel building projects, there hasn't been much to blog. I did procure some Chris King R45 hubs (20/24 hole) for a future project. I've also been adding to my knowledge by corresponding with Ric Hjertberg from Wheel Fanaytk about how spoke flanges and hub shells behave under compression from spokes.

For filler I am profiling the wheelset on my cross bike. I rock a steel frame/fork, so there's not much to be gained by racing a sick light wheelset. Besides, I like to keep it interesting when racing, so in the spirit of that I often make questionable choices in the lines I ride, the equipment I choose, and whether I ride or run a section. (On that last one: always ride.)

I started with a solution looking for a problem: a 20 hole front hub. Later I added another solution looking for a problem: a set of 20/24 hole Velocity Chukker rims. Why that rim?

Those are some sweet specs for a low tire pressure, cyclocross application. What that diagram leaves out: 664 grams for the rim. That's about double the weight of an Ambrosio Nemesis rim or a Mavic Reflex. The 50mm carbon tubulars I use are about 400 grams, and the H Plus Son Archetypes are 450 grams. We're also talking rotating weight, so adding 200 grams handicap for each rim makes things really interesting.

Velocity's label includes helpful pictographs that indicate the rim's suggested uses: bike polo and free ride. Note the rim's weld that is clearly visible on the brake track. Not your finest work, Velocity. The tire is a 700 x 32 Continental Gatorskin.

The front wheel is 20 spoke and built around a C-4 hub that I picked up for cheap. It is a decent design, with the flanges pushed out to 39 mm, a solid forged hub body, and a stiff axle. I used 2.0 mm straight gauge Sapims and 14 mm Sapim Polyax nipples. Lastly, because the hub had been previously laced, I included spoke head washers to eliminate any extra gap at the spoke hole. (I nearly always include spoke washers when lacing wheels to used hubs.) The measured spoke tension with tire mounted and inflated (90 psi) is 115 Kgf. Not too shabby.

I needed a rear wheel. I have several perfectly acceptable ones, but they didn't match my front. (Aesthetics are very important even in cyclocross.) I needed a hub for my 24 hole rim, and short of shelling out serious cash for a Chris King or White Industries, there weren't many options. I did notice the Bike Hub Store was offering 24 rear hubs drilled 16 (drive) and 8 (NDS). That sounded promising--like another solution looking for a problem--so I went for it.

The rear wheel with 8 spokes/radial on the NDS; 16 spokes/2 cross on the DS. Lessons were learned.

The theory behind having half the spokes on the NDS is that those spokes could be equal tension to the DS (instead of 40-60% like a regular, evenly spoked rear wheel). Of course one needs a center drilled rim to do it right. Turns out that the Chukker isn't quite that rim. But I built it anyway and am riding it with no problems.

Warning: due to the additional system resources required, do not consume while calculating spoke lengths for a 2:1 wheel, or while lacing said wheel. 

Lessons learned: 1) builds that start as solutions-looking-for-problems will invariably lead to a compromised outcome; 2) the drive side needs to be laced 3x because 2x looks sort of funny; and 3) be prepared to live with the results of your experimentation (because it's unlikely that anyone else would want it and selling it would be irresponsible). That back wheel and I are like Dr Frankenstein and his monster.

Punked

The wily Shimano DH-3N72 dynamo hub. It's capable of generating 3 watts at 10+ mph. It will power your  LED headlight and vex your wheel builder, because its dimensions are so damn hard to find. For the record: 70mm for the spoke circle diameter, and 28.5mm center-to-flange. There are a variety of Shimano dynamo hubs other there, so don't assume those measurements apply to yours. I like the dynamos: they will light the road, but won't lighten your wallet or your bike.

Recent wheel building adventures since my last blog entry:

• Discovering the spokes were too long on the dynamo wheel I am building for my dad. The wheel was laced, the spokes were at 80% tension, and I was finishing off the wheel when I stripped a brass nipple. That should've been my first sign that something was wrong, because an aluminum rim will fold itself into origami before a brass nipple will strip. I cut the stripped spoke, threaded in a new one, and continued to the next spoke. That one also started to strip. Once I figured out that I had run out of threads on the spoke, I took the wheel apart and measured the spokes. They were 286; I needed 283. Tip: always measure your spokes before a build. You wouldn't believe how many times there will be an oddball length in the lot.
• The joy of carbon rims. As noted in previous posts, tall rims are exceptionally rigid, and as such they can mask vast discrepancies in spoke tension. Last night I finished the 50mm carbon tubular with the assistance of the Park Tool spoke tension map. The map made it a lot easier to spot under/over tensioned spokes, even though the rim was within truing stand tolerances.
• Losing the will to live. There's no worse feeling--in wheel building--than finding a fatal flaw once a wheel has been assembled. It happened this week with that super cool elbows-out front wheel I built. During the final truing it became evident there was excessive play in the axle/bearings/hub body. It was only a millimeter but that becomes amplified at the rim so much so that the final truing becomes impossible. Fortunately, my supplier was understanding and immediately dispatched a replacement hub. Still, that was a couple hours down the drain.
• Black spokes. I built my first wheelset with black spokes because I thought would look sweet. (It did.) That set: HED Belgian C2 rims, White Industries H2 & H3 hubs, DT Swiss Competition spokes, 32 hole and 3 cross all around. I vowed not to use black spokes after that because the coloring creates additional friction where spokes cross. That stiction is a small but annoying annoyance when tensioning a wheel.

In the queue:

• The best wheels of 2013 (aka Tod's wheelset).
• Gigantex carbon tubular rear/24 hole/White Industries T11. This rim has a spoke tension limit of 130 Kgf. Gigantex is arguably the best mass market Asian-sourced carbon rim. It is made in Taiwan. They don't sell direct to consumers, but the Bicycle Hub Store does stock them in 38mm and 50mm. (I also believe they are center-drilled for those of you with 2:1 spoking aspirations.)

Graphing the wheel

I'm not in any particular hurry with the wheel I am building, so I'm free to experiment. Last night I downloaded the Park Tool spoke tension mapping spreadsheet and charted my wheel. The wheel was true, round, and stress relieved.

This is for a rear wheel: the red represents the higher tension drive side spokes; the blue the  NDS. An evenly tensioned wheel will be round on this graph, devoid of peaks and valleys. This actually looks pretty good, but the spoke tension needs to be increased by 10%.

I busted out the spoke wrench and started tightening the drive side spokes. Slowly. 1/8 a turn until the desired tension was reached. At this spoke tension is can be easy to strip a spoke nipple whether it is aluminum or brass.

With the ideal spoke tension reached on the DS, I moved to the NDS and started by correcting the dish of the wheel. Once the wheel was true and dished I graphed the spoke tension once again.

The DS spoke tension is now uniformly 125 Kgf. That should be balanced by an ideal NDS tension of 50 Kgf. I haven't adjusted the radial trueness and you can see that on the graph: the #3 spoke reads low (a high spot on the rim); and the #9 reads high (a low spot on the rim). My next session with the wheel will balance the DS spoke tension and correct the radial true. Then this wheel will be done.

Miss this step and you'll look like an amateur. The hub logo shall always be aligned with the valve hole.