Almost 20 years after Stan Koziatek created his first tubeless-ready rims, Stan’s NoTubes has introduced the new Crest, Arch, and Flow MK4 and S2 series aluminium rims and wheelsets.
MK4 rims and wheelsets
Building upon experience making asymmetric carbon rims that incorporate patented Bead Socket Technology (BST), Stan’s developed the MK4s, its first asymmetric aluminium rims. The company notes that the BST-Asymmetric design allows for an improved bracing angle and nearly equal spoke tension balance, while also maintaining easy inflation and airtight seal in the tubeless rim design.
The new MK4 series rims are available in three updated widths. Each of the Crest, Arch, and Flow models has its own purpose-built, wider rim shape and spoke hole offset.
The new MK4 design helps to give a balanced pressure along the drive and non-drive-side tyre beads and a consistent impact resistance on both sides of each rim.
Crest, Arch, and Flow MK4 rims are made of 6069 aluminium with a welded seam. They have a reinforced spoke bed and walls, and feature a matte-blasted finish. MSRP in the US is US$129.00. MK4 rims include a three-year warranty with crash replacement support and are available now.
Built for gravel and cross country riding, Crest MK4 rims have an internal width of 25mm with a spoke hole offset of 1.5mm and are optimized for 40mm gravel tyres, up to 2.3” mountain tyres. Offered in 20”, 24”, 26”, 27.5”, and 29” versions, the Crest MK4 rim weighs 374g for the 27.5” version and 399g for the 29” version.
Arch MK4 rims are billed as the most versatile of all Stan’s rims and are for a wide range of trail riding. They have an internal width of 28mm for 2.2-2.5” tyres and an offset of 2.5mm. Available in 24”, 26”, 27.5”, and 29”, the 27.5” Arch MK4 rim weighs 451g, while the 29” version weighs 481g.
The Flow rim has earned Downhill World Cup and Enduro World Series wins. With emphasis on strength and durability, Flow MK4 rims have an internal width of 30mm for 2.3-2.6” tyres. Available in 26”, 27.5”, and 29” versions, the Flow MK4 rim weighs 487g in 27.5” and 521g in 29”.
MK4 complete wheelsets will be available in late 2021 and will feature an entirely new M-Pulse hub design that will be shared with all Stan’s high-performance aluminium and carbon wheels.
S2 rims and wheelsets
Like the MK4s, Stan’s S2 rims have also increased in width, but they are manufactured with 6061 aluminium using a durable sleeved joint and stainless steel rim eyelets, and they rely on Stan’s conventional symmetrical Bead Socket Technology for easy inflation.
S2 rims come in the same widths and are for the same recommended tyre sizes as the MK4 rims. The Crest S2’s 25mm internal width is for gravel tyres from 40mm up to 2.3” mountain bike tyres. The internal width of the Arch S2 is 28mm, and it is optimized for 2.2 to 2.5” tyres. Flow S2 rims have an internal width of 30mm, for 2.3 to 2.6” tyres.
S2 rims are being spec’d on select complete bicycles, and S2 complete wheelsets will be available from independent bike shops and online stores in August. They will have an MSRP in the US of US$595.00 and include a two-year warranty on the rims.
