Frequent Questions

Derby Rims promotional bike industry wholesale and employee pricing is available for your shop's customer wheel builds, resale, and for you if you are full time employed in the bike industry. Please email info@derbyrims.com, and include your shop name or bike business, and your management title or your manager's name and contact in the email.

Are you a very active bike-community advocate or trail builder professional or very active volunteer? Or are you an experienced bike racer and compete very often in regional, state wide, or national bike racing series?

Derby Rims wants you to promote Derby's to your bike community and race friends, and to periodically report to Derby Rims your promotional activities with event pictures which show your Derby rims. Ambassador discount pricing can become available for you and your whole team. Please email your bike-community advocacy position and activity, or racing resume and next year's racing plan, to info@derbyrims.com. 

Tire inserts used with any carbon fiber rim require the same tire pressures as needed when riding with no inserts to produce any added protection improved rim protection.

After much Derby Rims testing and rider reports, Cush Core and other brands of tire inserts add little to no protection from sharp hits for any carbon rims. Most Derby rims reported damaged in the last few years had tire inserts. 

DH casing tires are more protective than any tire insert with about the same weight gain. Inserts do add tire wallow handling support for tire sidewalls much like double wall casing in DH tires. 

Aluminum rims, unlike carbon rims, do gain some added protection using heavy tire inserts. Inserts in aluminum rims spread out and reduce the depth of dents from sharp hits and reduce tire punctures with commonly sharp edged aluminum rims. Carbon rims do not dent.

No nipple washers are required for rim strength and durability, unless the nipples are undersized in rim surface flange size compared the normal 6mm flange width, such as when using internal tower nipples. Smaller internal nipple rim spoke holes can be special ordered, so that no washers would be required for internal nipples.

14mm or 16mm nipples produce a better appearance in carbon rims. Standard 12mm nipples also work fine, but look very short in carbon rims.

A spoke tension gauge is REQUIRED to build durable wheels.

Here is a link to the DT Swiss spoke calculator. It has their DT Swiss hubs in their drop down list, otherwise you need to get the hub specs or measure the hubs for the spoke hole center and flange width numbers needed for the calculator.

http://spokes-calculator.dtswiss.com/Calculator.aspx

You will need the ERD (Effective Rim Diameter). The ERD measurement is listed above in the rim specifications.

Use the "rounded" (stretched by tensioned) spoke length measurement calculated, and round up or down to a whole mm number get the length of spokes to order.

Professional wheel builders tend to be very exact and want perfect measurement for each side, each flange. The DT Swiss spoke calculator can provide the precise lengths if you want exact length for each side to evenly fill the nipples to the maximum without being too long.

There are many videos on U-Tube and guides on line for wheel building if you search with google.

Some deflated tires are difficult to remove over the bead retention ridge without using the following technique:

Lay a short section of the rim with deflated tire over a log or arm of a couch, or any platform surface,

Hold up the majority of the wheel behind the platform edge level with one hand,

Grab the tire hanging over the platform edge tightly with the other hand, and quickly push down with your palm on the sidewall near the rim.

The bead should pop down into the deep center channel pretty easily, and the rest of the bead can be peeled over the retention ridge into the center channel after the initial section pops over.

For Derby 25i rims: 28mm to 55mm gravel tires and 1.8-inch to 2.25-inch mountain tires are ideal. Very light short tread XC race tires up to 2.4 are OK.

For Derby 30i rims: 2.0 to 2.3-inch mountain tires are ideal, up to 2.6 tires are OK. 45mm gravel tires or 1.8-inch mountain tires are OK for XC gravely and hardpack conditions.

For Derby 35i rims: 2.4 to 2.6 tires are ideal, and up to 2.8 tires are OK. Tires as narrow as 2.25-inch mountain tires are OK for XC gravely and hardpack conditions.

For Derby 40i rims: 2.6 to 3.0 tires are ideal, and up to about 3.4 tires are OK. Tires as narrow as 2.4-inch mountain tires are OK for XC gravely and hardpack conditions.