DT Swiss 350 2021 + Rear Black ISO 6 Bolt Disc Hub
If we had to pick one hub to build every wheel on for the rest of our careers, the 350 would be on the shortlist and would probably win. The 350 is not the lightest hub DT Swiss makes and it is not the flashiest. It is the one that keeps coming back to the shop only because the customer wants a new rim laced to it. The DT Swiss 350 uses the same Ratchet System as the 240 and 180, in a slightly heavier hubshell with a plainer finish, at a price that leaves room in the budget for a better rim.
This page covers the 2021-and-later DT Swiss 350 2021 + Rear Black ISO 6 Bolt Disc Hub. The factory reworked the 350 in 2021 with the current Ratchet System, a stiffer axle and the plug-in freehub that pulls off by hand, so an XD to Micro Spline swap on a 350 is a two-minute job with no tools.
We sell the 350 only inside a wheel we build. Choose the rim, spokes and nipples in the configurator and the finished 350 wheel ships from our shop in Georgia, laced, tensioned and trued by hand.
Design and construction
The Ratchet System is what sets these hubs apart from a pawl hub. Two spring-loaded star ratchets with 36 teeth each engage across their whole face at the same time, so the load of a hard pedal stroke is spread over the entire ring rather than concentrated on two or three pawls. That is why a DT freehub is hard to break and why the 350 is so easy to service: pull the end cap, slide the freehub off, wipe the ratchets, grease, reassemble. No tools. The 36-tooth ratchets in the 350 give ten degrees of engagement, and you can drop in the DT 54-tooth set later if you want it quicker.
The 350 hubshell is a milled aluminum body on a lightweight axle with sealed cartridge bearings. On the 2021+ DT 350 the axle is stiffer than the old version and the end caps are the plug-in type, so the same 350 hub converts between quick release and thru-axle standards with a cap change. The flange spacing is classic DT, which means every spoke calculator on earth knows the 350 and the wheel builds true first time.
DT also offers the 350 with the Ratchet DEG 72-tooth freehub, its fastest-engaging system, if five degrees of pickup matters to your riding.
How it rides
A DT 350 does not draw attention to itself, which is exactly what you want from a hub. The freehub engages with a firm, quiet click, coasting is nearly silent, and the bearings run for years between services if the seals are left alone. Road riders get a 350 that is as smooth as anything twice the price; mountain bikers get a freehub that does not skip under a stomp on a wet root.
Where the 240 and 180 save weight with more expensive machining and materials, the 350 gives that up for the same engagement, the same serviceability and the same reliability. For most riders the 350 is the right trade.
Specifications
| Position | Rear |
|---|---|
| Axle options | QR 5x135mm Rear, QR 5x141mm Boost Rear, Thru Axle 10x135mm Rear, Thru Axle 12x135mm Rear, Thru Axle 12x142mm Rear, Thru Axle 12x148mm Boost Rear |
| Driver bodies | Shimano HG 8,9,10 & Dynasys MTB 11spd, Shimano HG 8,9,10,11 & Road 12spd (+$30), Campagnolo 9,10,11 & 12spd (+$30), SRAM XD 10,11 & MTB 12spd (+$48), SRAM XDR 10,11 & Road & MTB 12spd (+$60), Shimano Micro Spline 12spd (+$60) |
| Drillings | 28h, 32h |
| Spoke head | J-bend |
| Brake | 6-bolt disc |
| Left flange diameter | 60 mm |
| Right flange diameter | 50.5 mm |
| Spoke hole diameter | 2.6 mm |
| Weight | 283g |
| Material | Aluminum |
| Finishes | black |
Which version this is
Version notes. 6-bolt rotor mount, QR 5x135mm, QR 5x141mm Boost, Thru Axle 10x135mm, Thru Axle 12x135mm and more, 28h, 32h, about 283g, in black. If your frame or fork uses a different standard, the other versions of the 350 on this site cover it.
This is the 6-bolt 350: the rotor bolts to a flange with six T25 bolts, which is the mount most mountain and gravel rotors still use and the easiest to find a rotor for on the road. If you run centerlock rotors, choose the centerlock version of the same hub instead.
Sizes, fit and compatibility
The DT Swiss 350 2021 + Rear Black ISO 6 Bolt Disc Hub comes in the drillings listed on this page and in the axle and rotor options shown in the configurator: centerlock disc, 6-bolt disc or rim brake, road and MTB spacings including Boost. A rear DT 350 takes Shimano HG, SRAM XD or XDR and Micro Spline freehubs, all swappable without tools.
The 350 is a J-bend hub, which opens up every spoke we stock. We build the 350 onto DT Swiss rims, Stan's, WTB, Race Face, HED, Velocity and most carbon rims in the catalog. Tell the configurator your bike type and weight and it will suggest a spoke count that suits the drilling you pick.
Build it into a wheel
This hub is live in our Custom Wheel Program for gravel and road disc, mountain bike and fat bike builds. Start a build with the DT Swiss 350 2021 + Rear Black ISO 6 Bolt Disc Hub and the configurator opens with this exact hub pinned at the top of the DT Swiss list — you choose the rest of the parts and it validates every combination as you go.
DT Swiss's testing and certifications
DT Swiss hubs pass through the same Performance Test Center in Biel as its rims. DT Swiss states that its laboratory tests replicate what products endure in the field over the whole product life cycle, under an internal factory standard that ensures compliance with ISO 4210. Hub-relevant methods are the drum test, in which a wheel loaded to its permissible system weight spins on an obstacle-studded steel drum for a specified mileage, and a brake and drive torque test in which cyclic braking and driving torques are applied to the hub while the wheel is locked or driven at constant speed. DT Swiss publishes no bearing-life, salt-spray or water-ingress figures.
the torque test also verifies "the freewheel functionality and durability". DT Swiss states that Ratchet EXP is 15% stiffer and gives longer bearing life through its increased bearing distance, and that Ratchet DEG uses larger steel ratchets to spread load over a larger contact surface. Ratchet EXP units built since 2019 with a 0 or 9 in the middle of the production code are covered by a free-inspection notice for premature ratchet wear.
DT Swiss's videos
From DT Swiss
Certifications
- ISO 4210 / ASTM F 2043 — DT Swiss states its internal factory standard 'ensures compliance with the current international standards (e.g. ISO 4210)' and sets test parameters by ASTM F 2043 riding conditions (self-declared, no certificate published) (source)
- Warranty — 24 months legal warranty against material and manufacturing defects; ball bearings are wear parts and excluded (source)
- Service interval — Clean and re-grease every 12 months (normal use) or every 3 months (extreme conditions) (source)
Sources on DT Swiss's site:
- Performance test center | DT Swiss
- Ratchet EXP maintenance notice | DT Swiss
- FAQ | DT Swiss
- Warranty & Fair-Share | DT Swiss
- Ratchet EXP | DT Swiss
DT Swiss publishes those results; ProWheelBuilder builds the hub into a wheel and does not test it in a lab.
Building it at ProWheelBuilder
DT makes the 350 in Switzerland and Poland; ProWheelBuilder is an independent custom wheel builder in Georgia, not the manufacturer. We have built enough DT 350 wheels to know its flange dimensions by heart, but we still cut spokes from the measured geometry of the rim in hand and bring every wheel up in stages with a tension gauge before truing and stress-relieving it.
The configurator shows only rims and spokes that can be built with the drilling you choose, strikes through combinations that are not made, and prices the wheel live.
Warranty
DT Swiss's warranty. DT Swiss covers its products against material and manufacturing defects for 24 months from purchase, excluding wear parts such as bearings and tubeless tape. Carbon rims and carbon wheels bought new since 1 January 2020 carry an extended guarantee to the first owner against defects in material and workmanship, and DT Swiss runs a paid crash-replacement scheme on carbon wheels for up to ten years from purchase.
ProWheelBuilder. Wheels we build around this part are covered by our own one-year warranty alongside the maker's. Within the year: broken spokes replaced regardless of cause, and the labor on the wheel - truing, re-tensioning or a complete rebuild - included. A manufacturer-covered rim or hub failure is a claim we make and manage for you; one they will not cover is answered with an eligible replacement at 25% off retail. Shipping each way is yours. Parts you supply yourself fall outside it.
Full terms are on our Policies & Warranty page.
350 2021 + Rear Black ISO 6 Bolt Disc Hub questions
Will my rotors fit this hub?
This is the 6-bolt version: any ISO 6-bolt rotor bolts straight on with six T25 bolts, which is still the most common and the easiest rotor to replace anywhere. Centerlock rotors do not fit it - for those, take the centerlock version of the same hub, listed separately.
What is the difference between the 350 and the 240?
Internals are the same Ratchet System. The 240 has a lighter hubshell and axle and costs more; the 350 is the same engagement and serviceability for less money. Most riders will not feel the difference on the road.
Can I upgrade the engagement on a 350?
Yes. The 36-tooth ratchets swap for the DT 54-tooth set in a few minutes with no tools, taking the 350 from ten degrees to under seven.
How do I change the freehub body on a 350?
Pull the end cap, slide the freehub off the axle, slide the new one on. The plug-in design needs no tools and no special knowledge.
Is the 350 rated for e-bikes?
DT approves the 350 for e-bike use. Tell us it is an e-bike build and we will pick spokes and a lacing pattern to suit the extra torque.
Is ProWheelBuilder the manufacturer of the DT Swiss 350 2021 + Rear Black ISO 6 Bolt Disc Hub?
We are not. DT Swiss manufactures the hub; ProWheelBuilder's part is the wheel: measuring, lacing, tensioning and truing it here in Georgia.
Which axle spacing does it fit?
QR 5x135mm Rear or QR 5x141mm Boost Rear or Thru Axle 10x135mm Rear or Thru Axle 12x135mm Rear or Thru Axle 12x142mm Rear or Thru Axle 12x148mm Boost Rear. Measure between the inside faces of your dropouts if you are unsure, or text us.
Not sure? Text or leave a voicemail on 470-253-0929 or email info@prowheelbuilder.com — you will be talking to the people who build the wheels.
