Sol Rider "SR" clear finish rim model line

Testing by dozens of extreme MTB riders over 3 years had zero failures!

Currently in Spring 2023, just 1 intended riding use cracked Sol Rider rim over 5 years!

Derby Rims original goal to achieve a zero rate of rim damage had been achieved for over 4.5 years including extensive testing for 3 years by Pro and CAT-1 Downhill and Free-Ride extreme testers of the new “Sol Rider” (SR) model line. 

Currently in 2023, after more than 5 years including 2 years of sales only one very frequent Enduro and DH racer and park rider was able to crack the first Sol Rider rim while riding Sol Rider rims as intended.

The exclusive Sol Rider line of Derby Rims utilize a proprietary "Carbon Fiber Reinforced Polymer" (CFRP) hybrid aerospace industry developed layup of carbon-fiber and plastic fiber composites, Derby Rims calls the “Solstice” layup. Derby Rims has utilized a US designed plastic composite fiber UD combined with UD carbon fiber within a proprietary layup schedule.

The Sol Rider (SR) model line rims had tolerated more than three years with no (zero) damage during extensive test riding by Pro and CAT-1 riders, beginning in 2018, including DH racing, Enduro racing, and Free-Ride 35 foot gap jump testing, followed by dozens of other test riders. 

The Sol Rider (SR) line of mountain, and gravel bike rims are available in 29 x 30i (30mm inside width), 29 x 35i, and 27.5 x 35i sizes for mountain bike XC/Trail and Enduro/DH tire uses, and 29/700c x 25i for gravel road bike and XC mountain bike tire uses, with a 5-year free damage replacement policy for original owners and a lifetime extended replacement warranty including secondary owners.

During initial testing in 2018 and 2019, the first wide profile light weight 485g 27.5 x 35i (35 mm inside tire bead wall width) SR model test rim was “expected to fail very quickly” by the first test rider Austin Fotinas, a recent Pro category downhill racing champion and free-rider. He proceeded to test while training with downhill race runs and 35 foot gap jumps, which were tolerated for 2 years with no damage. Another test rider, Kevin Dwyer, a massive jump free-rider and Cat-1 masters DH racer reported, “these are the smoothest carbon-fiber composite rims I've ever ridden”. For more than 3 years of machine load and dozens of advanced and expert riders testing, there were no (zero) Sol Rider test rims ever damaged utilizing the Solstice hybrid composite layup.

The smoother ride compared to the same design as the firmer feeling of 100% carbon fiber UD Derby Rims of the same sizes is enabled by the more flexible "Solstice" hybrid layup use of proprietary plastic UD layers layered between layers of carbon fiber UD. The plastic fiber layers microscopically stretch between alternating layers of carbon fiber in the Solstice layup when flexed excessively by an unintended hard impact or acute weight load to the rim while riding. The increased Sol Rider rim wall flex tolerance prevents “micro-fracturing”. 

Micro-Fracturing is initial fibers separating within one carbon fiber "tare" (one thread of multiple carbon fibers), leading to further separation of internal tares and layers, until the rim wall can no longer support intended loading and collapses showing as a surface sidewall crack of a rim, which was initially caused by acute and excessive flex. Unless a sharp pointed object punctures a rim side wall, a rim wall crack of the most durable Derby rim is always from initial internal micro-fracture, and can be nearly instant from one very sharp hit. But usually the initial micro-fracture occurs from a very sharp hit many months, even years before the internal fiber and layer separation increases from normal riding flex enough to collapse and show as a rim surface crack.