We are pretty proud of our latest wheel build and we wanted to share the particulars with yinz. On the surface this particular set looks pretty normal. We used the Velocity Dyad rim (a shop favorite for a strong touring and commuting rim) and laced them to a DT Swiss 350 disc hubset (another shop favorite for serviceability and sealed bearings). If you take a closer look at the rear wheel though you might notice that although the hub is spaced for the road bike standard of 130mm it has mounting points for a disc brake rotor. This is unusual because DT Swiss does not make a 130mm spaced disc hub. Typically road bikes with rim brakes today have 130mm spacing where mountain, cyclocross, hybrids, and pretty much all disc brake bicycles share 135mm spacing ( except for the newer 142X12 for modern fancy mtbs and some cross bikes). So the question is why and how did we create a 130mm spaced rear wheel with disc brake capability?
It goes a something like this. We were approached by a high mileage customer, someone that rides well over 10,000 miles a year about a replacement wheel set for his current bike. Us, loving hand built wheels suggested that we build him a nice sturdy set capable of taking a high mileage beating and asking for more. We then considered that this particular customer may wear our his current bike (drivetrain, frame, etc...) before this new set of wheels. In this situation what value would they still offer?. To compound this issue this customer's current bike is a funky hybrid that is spaced like a road bike at 130mm rear spacing, but a new bike would most likely be spaced 135mm and probably have disc brakes.
We decided that It would be great if we could build a set of wheels that would fit his current bike (130mm spacing, and rim brakes) but be easily modified to fit either disc brakes, 135mm spacing, or both. After calling around we found that one of our favorite hubs the DT Swiss 350 rear hub can be converted to road spacing with the some basic end cap swaps. All we needed to do was order an non drive side end cap designed for their road spaced 130mm hubs and use that cap to replace the stock mountain axle cap. Check out the picture below to see what I'm talking about. On the right you can see the shorter replacement end cap and on the left the stock cap. The difference in length is the needed 5mm reduction.
Getting the Hub spaced down to 130mm was only the first step. After re-spacing the hub we needed to employ some basic math to calculate the proper spoke length and make sure we could properly dish the wheel with the new measurements. We also wanted to make sure that when the wheels were spaced back to 135mm the spoke lengths would be appropriate to allow the wheel to be re-dished (dishing is centering the rim in the center of the hub) for the new hub width.
Check out these hieroglyphics. Katharine is calculating the new hub dimensions after losing 5mm on the non drive side which is important for spoke length calculations. We are also looking at the bracing angles to make sure the spoke are leaving the huge at an appropriate angle to support the rim.
These wheels were a ton of fun for us to design and build. Although someone probably has done this before we weren't able to find anyone writing about it on the interment. Breaking new ground (at least in our personal experience) is always exciting. If you read this and wanted more of the nitty gritty technical data like spoke lengths or tension feel free to email us and we can get into greater depth, Thank for tuning in!