Phatty 85mm
Created for the type of rider willing to take two wheels into conditions that would leave lesser mountain bikers safely indoors, the all-new Atomik Carbon PHATTY 85mm is here. The single greatest upgrade available for any fatbike, the PHATTY 85 features a monster 85-millimeter width (77-millimeter inner diameter) to maximize the footprint of your fat tires and give you a ride with ungodly grip in all conditions.
Featuring HDP (High-Density Performance) Foamcore technology and Solowall construction, this aerospace-inspired carbon fat rim sets the standard for strength, weight and ride quality with an impressive 16-millimeter low-profile design engineered to minimize damage from trail shrapnel to keep them looking better longer. The minimal surface area also means the nasty stuff you’re likely to encounter in loose conditions where big tires shine—from snow, to muck, to sand—won’t have much to cling to, reducing unwanted weight and mess.
Although the PHATTY 85mm is deceivingly light at 590 grams, don’t be fooled—it’s still a heavyweight built to take abuse. Light can be strong, and that’s why we wrapped our high-modulus blend of Toray 700 and 800 around our aerospace-grade HDP Foamcore to enhance stiffness and damping qualities for a ride you’ll have to experience to believe.
A beefy 3.5-millimeter modified bead hook helps to dissipate the force of impacts through the sidewall when things get ugly, and BeadLock allows you to run lower pressures for maximum traction.
Throw a set on your fat bike and see how the Phatty 85mm can transform you ride.
Rims: $742.50 each
Complete wheel set starting at: $1,815
The Phatty 85mm features an aerospace foam core wrapped in a layer of composite material that is molded into the structure, creating a pseudo-semi wall rim that boasts increased impact strength, energy dissipation and stiffness, while adding additional damping characteristics.
An added benefit of the extreme low profile of the rim is a greatly reduced surface area. This ultra low profile reduces the amount of rim surface that is exposed to sidewall impacts and trail debris, therefor limiting the exposure of the rim to damage.
| Tubeless Ready | Yes |
| Hookless | No |
| Depth | 16.2mm |
| Width – O.D. | 85mm |
| Width – I.D. | 77mm |
| Bead Width | 3.5mm |
| Weight | 590g +/- 15g |
| Spoke Drilling | 32 – Directionally Drilled |
| Spoke Tension | Rec 120 kgf |
| ERD | 545 |
| Spoke Hole Offset |
13mm |
| Finish | UD Matte Carbon |
| Price | $675 U.S. msrp |
Bead Lock
All Atomik Carbon rims utilize an angled bead lock to keep the tire bead positioned on the shelf when air is released from the tire and also adds a level of safety if a tire is leaking. This features allows you to refresh sealant without having the tire bead fall into the center of the rim, resulting in a tire that is more difficult to inflate and re-seat.
Hooked Design
The hooked wall thickness is a whopping 3.5mm and designed to help displace impact. The wall thickness is much greater than traditional designs (as shown in the illustration above) and the additional strength provided by the thicker sidewall yields a rim that is light and extremely strong.
Impact Resistant Construction
The Phatty features an aerospace foam core wrapped in a layer of composite material that is molded into the structure, creating a pseudo-semi wall rim that boasts increased impact strength, energy dissipation and stiffness (illustrated above) while adding additional damping characteristics.