Friday, September 25, 2009

Setting up Your Cyclocross Brakes

Last year, I set up my new cyclocross race bike from scratch, piece by piece. It was the first time I've done so in about 7 years and for the most part, I was very happy with the bike. This year, aside from testing some new wheels and tires, the only thing I'll be changing is the brakes. I decided to post the details here since it may be instructive to some of you and proper brake set up does effect rim longevity.

Initially, I had the bike set up with TRP Eurox brakes. They are relatively light and inexpensive and the design is straightforward enough. Unfortunately, I just cound not get them set up to work very well. The most obvious problem was the lack of toe adjustment. Most cantilevers use smooth post pads that can be toed simply by bending them in a vice. A bit crude but it works. These however, use posts with a pad holder for standard road cartridge pads. Convenient, but less adjustable (they have since corrected this with an adjustable toe pad holder). In any case, it's not a big problem since any smooth post canti pad will work with them.

The bigger problem for me was that the geometry of the brake had the pad very close to the canti post and there was no vertical adjustment available. The pad had to be angled sharply upwards to meet the rim. Ideally, the pad will hit perfectly perpendicular to the rim with an appropriate amount of toe-in. This was impossible to achieve with these brakes.

This is bad in two ways: 1) Brake performance is subpar and 2) The rim receives added stress due to the smaller contact patch of the pad, leading to premature rim wear.

To be fair, this may not be an issue for all bikes. Canti posts may be set higher on other frames and forks that may make this less of an issue but for my particular set up (Cannondale CAAD 9 with Easton EC90 fork) there was no way to make these brakes perform to my standards.

So what to replace them with?

I decided that my brakes for this year would need two things: toe adjustment and pad height adjustment. The two brakes I was considering with these features were the Avid Shortys or Paul Neo Retro/ Touring Canti.

Initially, I thought I'd go with the Avids. They are a good bit cheaper and work well. Additionally, they use road cartridge pad holders with V-type adjustment features making them very convenient for set up and pad changes. The did have one issue that ended up being a dealbreaker: no straddle cable. Normally, I wouldn't really care but I had been using these super awesome novelty straddle cable holders that I found in a dusty bin somewhere, a relic of early 90's when mountain biking was trendy and V-brakes had not yet gained dominance (I think there were also some purple annodized peace sign straddle cables in the bin with them and I can only assume they will stay there for all of eternity).


But the Paul's had issues as well. I did like the low weight and great retro looks and the ability to use the stonger Neo Retro model on the front and the calf saving Touring Canti in the back. However, the brake pads, standard V-brake rubber, were not as appealing as the Avids. Luckily, Avid sells their Shorty pad holders separately and after a quick addition of the glorious Swissstop Yellow King inserts, I was in business.






I rode the bike with the new brakes for the first time this past weekend at Charm City. These are the best brakes I've ever used, hands down. They were quiet, predictable and smooth, even with brand new carbon rims and much better and quieter than my bike last year with alloy rims.

Tuesday, September 22, 2009

A few models are out of stock

Like all sensible Europeans, everyone at Sapim takes a break during the month of August. As a result, we're running short in a few lengths for the CX-Ray and are unable to build a few models for the next week or so until we get some more spokes in. We are effectively out of stock in the following models: REV-25x, REV-30L, REV-30 & REV-50x. Feel free to backorder the wheels through the site. As soon as the wheels are available, I'll contact you to let you know when they will ship.

We're also starting to run low on hubs in the 24/28 drilling so there may be some addtional inventory issues going into the fall. We should be fully stocked in everything by late November.

Even when we're out of stock this fall, you can always rent the REV-50x for cross races this fall from Echappe Equipment. Rentals are $50 for the day and anyone who rents through Echappe gets a discount code for $50 off the purchase of any of our wheels.

Monday, September 21, 2009

Cross Season is Here! Weekend Recap

Photo credit: David Lowe (I think so anyway since I stole it from his blog)


The first major race weekend of the season has come and gone and it was a good one for us. While I couldn't make it to Trexlertown for the first round of the MAC series, I did get to Baltimore for Charm City. The Evil Empire, er... C3 put on a great event that seems to get bigger and better every year. It's one of my favorite courses and the perfect event to kick off the season.

Our sponsored riders were out in force this weekend. The HumanZoom/PBR women had some great results with Kristin Gavin getting 5th both days on her 25x tubulars paired with Grifo XS tires. Nikki rode the REV-25x with Fangos to an 8th place finish on both Saturday and Sunday. Kristine Church rode a set of the REV-30s to 16th place on Saturday and 18th on Sunday. A stealth set of REV-50s may or may not have won the elite women's event both days but I'm not sure how much I can say about that one.

Ken Dietch (REV-50x) rode to 14th on Saturday and 25th on Sunday in the B-Masters races and David Lowe (REV-25x) held his own with the fastest old men out there to finish 11th and 10th over the course of the weekend.

Gabe Lloyd (REV-50) of Echappe Equiptment rode in the elite mens race to 26th on Saturday while nursing a wrist injury. Bill Elliston (REV-50) finished 15th in the elite race on Saturday and 22nd on Sunday.

Bill is a long time professional in the sport and we're excited to partner with him. He has brought his many years of experience in road and cross racing to his role as a coach with Elliston Coaching. If you're local to the area and looking for good coach, I highly recommend checking him out.

My race went well considering my complete lack of training this summer. I was pleasantly surprised to see that I had a first row starting position thanks to last season's points and I think I ended up somewhere in the top half of the 125 rider field. My cross bike, which I hadn't riden since January, performed flawlessly and I'm extremely excited about a pair of prototype cross wheels that I'll be testing this season.

The next MAC weekend will be Granouge and Wissahickon and we'll be sponsoring and exhibiting at the Wissahickon race. I can almost guarantee that we'll be sold out of cross wheels by that point but feel free to stop by and check out the wheels in person.

Lastly, I offer this to all of the good men and women working in the pits this cross season:

Saturday, September 5, 2009

Does Heavier Equal Stronger?

It's often the case that adding material, and therefore weight, to a component will make it stronger and more durable. With rims, for example, this is generally true. So does a heavier wheel always make for a stronger, more durable and more resilient wheel? No. Anytime we have an opportunity to make a wheel lighter while maintaining the same or greater durability, we try to take it. Our alloy cross wheels, the REV-25x, for example weigh 1460g. Not spectacularly light but given what they are built for, they are significantly lighter than most other alloy wheels being sold for cyclocross use. So how do we make a stronger, lighter wheel? We've carefully sourced all our components but much of the credit goes to the often overlooked spoke.

Invisible components

Next time you're looking over some mid to high range road or mountain bikes, check the specs to see what headset, bottom bracket and cassette are used. Are they on par with the other components on the bike? Probably not. These are very important components but most manufacturers will source them as cheaply as possible since most people won't bother to look at these parts in much detail. Spokes too, are largely invisible to the consumer. Most people can differentiate between round or bladed and silver or black, but that's about it. The subtle variations in thickness, forging techniques, nipples, etc. and the associated benefits and costs are easy to overlook. It's no surprise then that most manufacturers will use cheap spokes to cut costs.

We use Sapim CX-Ray spokes for all our wheels. These are the gold standard for spokes and are very expensive. What makes the CX-Ray so great is that it is both the lightest available steel spoke and also the strongest and most aerodynamic. Most wheelsets in the same price range of ours use much cheaper spokes. A straight 2.0mm (14 gauge) spoke weighs about 7 grams. A CX-Ray spoke weighs about 4.5 grams. On a 24/28 spoke wheelset, this is a weight difference of more than a quarter pound. Aerodynamic advantage is more obvious. Round objects don't go through air very well. Oval objects do. A round spoke with a 2.0mm cross section will be significantly less efficient than and oval spoke with a 0.9mm cross section.



But wouldn't a thicker, heavier spoke be stronger?


When discussing shear strength (the force needed to cut through it) yes, the 14 gauge spoke is stronger. Generally speaking though, when we throw around terms like strength and durability with regard to spokes, we are talking about fatigue resistance. And no spokes has been tested to have better fatigue resistance than the CX-Ray. As the wheel rotates, the spokes at the bottom of the rotation lose tension to some degree. Each spoke on the wheel is cycling from a lower to higher tension with every rotation of the wheel. These constant stresses on the spoke will eventually lead it to fail, typically at the spoke head or where the spoke leaves the nipple. Straight gauge spokes have the least fatigue resistance. Their uniform thickness does not allow them to efficiently absorb the stresses that a wheel experiences as it rotates and the spoke will break much sooner than a more flexible spoke. The CX-Ray is 14 gauge (2.0mm) at the spoke head and nipple threads but swaged (or butted if you will) to 17 gauge (1.5mm) at the center. That butted section is then forged to an oval shape that is 2.3mm x 0.9mm. This makes for a very flexible spoke that is much better at absorbing the stress that the wheels experiences as they rotate under load. There is a reason that top mountain and BMX racers insist that their wheels are built with these spokes and it doesn't have much to do with their aerodynamic properties.


The nipples are also important. Unlike just about every other nipple on the market that leaves the rim at a fixed angle, the Sapim Poly-ax nipple allows for a subtle angling of the nipple as it leaves the rim. This allows for a straighter path for the spoke from the hub to the rim, resulting in less stress to the spoke.



So why isn't it more widely used?

As I mentioned before, it's very expensive. The CX-Ray costs more than 8 times as much as a straight gauge spoke by Sapim and more than 10 times as much as straight 14g spokes from Asian suppliers. These costs can be hard to justify when the buying public has very little knowledge about what makes one spoke better than another and when the stronger spoke is paradoxically much lighter than the weaker one. Being a smaller manufacturer (I can only build so many of these things), we can ignore the mass market and give our customers a bit more credit when it comes to evaluating our products based on the important details that are often lost in the marketing of most products in this industry. This topic probably deserves its own post (and every time I try to write it, it comes out way too arrogant) but I genuinely believe that there are a lot of bad products out there simply because they are designed around what consumers think they want instead of what experts know is best (cheap ceramic bearings is a good example of this).

How can we use such expensive componentry on such reasonably priced wheels?

I've answered this here to some extent but it basically comes down to selling direct to the consumer and disciplined cost management. We're a very good size for what we do. We can purchase our materials in large enough quantities to maximize economies of scale, minimizing variable costs. But since we're so small, fixed costs can be kept to a minimum. We're happy to grow our business organically so we have no debt to service or outside owners to please and we don't have to sell too many wheels to sustain our operations.

Wednesday, September 2, 2009

Truing Wheels with Thin, Bladed Spokes

All of our wheels are carefully built to tight tolerances and appropriate, equal tension. They are stress relieved before finishing. Even so, they may need the occasional tweak with a truing wrench. While I suspect most of you will be taking these to your LBS for such service, if you're familiar with the process and have the right tools, there's no reason why you can't do it yourself. If you've only worked with round spokes in the past, however, your tools and technique may need to be adjusted.

Thin, bladed spokes like the SAPIM CX-Ray that we use must be held in place when turning the nipple. Otherwise, the spoke will just twist right along with the nipple. Sapim does make a tool for this, but in my opinion, it's an overpriced piece of plastic with limited utility. I like to use it when working with internal nipples on our carbon rims but with traditional nipples, the tool needs to be placed too high on the spoke to really be effective.



The spoke holder I most prefer for this is made by DT Swiss for their aerolite spoke. Since the spoke dimensions for this and the CX-Ray are essentially the same, I find it works just as well for either.

As you can see, this is a sturdy piece of steel that holds the spoke at its base, allowing one to turn the nipple without twisting the spoke, even at high tensions.

As for the wrench, a 4-sided model with clearance for the holder is recommended. I use the Park Tool SW-20 but I'm sure there are others out there that fit the bill.

2-sided:


4-sided:
DT spoke holder and Park SW-20 at work: