WTB KOM Tough TCS I 30 Rim
The WTB KOM Tough is the alloy trail rim that shows up on more bikes than almost any other, and the i30 is the width most trail riders want: 40mm inside for 2.4 to 2.6in tires, about 552 grams in 29in and 517 in 27.5in, with WTB's TCS tubeless bead, 4D angled spoke drilling and an I-Beam center support. Tough is the heavier of WTB's two KOM layups, built for trail and all-mountain riding, and it is one of the best-value alloy rims we build.
This page covers the WTB KOM Tough TCS I 30 Rim in 29in, 27.5in. The KOM Tough i30 comes from us only as a finished wheel: pick the hub, spokes and nipples, and we lace, tension and true it by hand in Georgia before it ships.
Design and construction
TCS stands for Tubeless Compatible System, WTB's bead profile that seats a tubeless tire with a floor pump and holds it at low pressure; the KOM Tough needs 35mm TCS tape and a WTB valve, which we fit. The I-Beam is a vertical web inside the rim section that stiffens the spoke bed, and 4D drilling angles each spoke hole toward the hub flange it serves so the nipple sits straight and the spoke does not bend at the rim. The KOM Tough is a welded 6069-class alloy rim with thicker walls than the KOM Light for the same profile.
WTB makes the KOM Tough in i25, i30, i35 and i40 inner widths; the i30 is the trail all-rounder. Standard nipples, J-bend spokes, 32 hole, disc only.
How it rides
A KOM Tough i30 wheel is a wide, stable trail wheel that takes abuse. The 30mm bed gives a 2.5in tire a square shape at low pressure, the welded rim shrugs off rock strikes, and the 4D drilling means the wheel builds to even tension and stays there. It is not the lightest 30mm alloy rim and it is not trying to be; it is the one that keeps working.
For cross-country the KOM Tough i25 is lighter; for plus tires the i35 and i40 are wider; for e-bikes and gravity WTB makes the thicker-walled HTZ. For trail and all-mountain riding, the KOM Tough i30 is the WTB rim we recommend.
Specifications
| Wheel size | 29in, 27.5in |
|---|---|
| ERD | 605 (29in), 570 (27.5in) |
| Inner width | 40 mm |
| Drillings | 32h |
| Weight | 538g (700c/29in), 510g (650b/27.5in) |
| Material | Aluminum |
| Tire type | clincher tubeless compatible |
| Brake | Disc |
| Nipples | External |
| Finishes | black |
About this listing
Version notes. 29in, 27.5in, 32h, about 538g, 40mm inside, mm deep, disc. The other sizes and brake versions of the KOM Tough i30 have their own listings; this page is for this one.
This is the disc-brake KOM Tough i30: plain sidewalls, no brake track to wear, a touch lighter. It fits any disc-brake bike and it is the version most of our customers now build; the rim-brake version is a separate listing.
Sizes, fit and compatibility
The WTB KOM Tough TCS I 30 Rim comes in 29in, 27.5in and 32h drilling. It is a disc-brake rim. We build the KOM Tough i30 on DT Swiss 350 and 240, Industry Nine 1/1 and Hydra 2, Hope Pro 5, Onyx Vesper, Bitex BX 211 and Velocity Race hubs, usually with Sapim Race, D-Light or DT Competition spokes and brass nipples.
Tire range on the KOM Tough i30 is 2.3 to 2.6in. Pick your bike type and weight in the configurator and it recommends a spoke count and lacing pattern.
Put it in a custom wheel
Build a custom wheel around the WTB KOM Tough TCS I 30 Rim — the link drops you into our Custom Wheel Program with this rim pinned, ready for you to choose the rest. It is set up for tandem and e-bike, MTB single-speed, mountain bike and fat bike builds.
Spoke head is decided by the hub, not the rim: this rim builds equally well with J-bend or straight-pull spokes, and the configurator only offers the spokes that match the hub you pick.
Testing, standards and warranty at WTB
WTB (Wilderness Trail Bikes, California) builds its rims around the TCS tubeless system. WTB states the Beadlock bead profile is "Designed to ISO/ETRTO standards", that 4D drilling angles each spoke hole toward the hub flange, and that most alloy rims are sleeve-jointed, the rim ends hydraulically pressed over an extruded aluminum insert reinforced with industrial epoxy. KOM and HTZ rims use 6069 aluminum for its "high tensile and fatigue strength"; HTZ e-bike rims add 20% wall thickness over KOM Tough.
Warranty: WTB guarantees its products "for at least two years"; Ci24/Ci31 carbon 36 months. CZR carbon rims carry a Limited Lifetime warranty for the original owner plus the Ride With Confidence Guarantee: a CZR broken while riding is replaced free with a free rebuild; one damaged while not riding is replaced at 50% off current MSRP.
Published limits: maximum spoke tension 110-120 kgf on KOM, HTZ and CZR rims; max rider weight 265 lbs for the CZR i23 and 300 lbs for the CZR i30. No per-rim maximum tire pressure is published and no ISO 4210 or UCI certification is claimed.
WTB's videos
Certifications
- ISO/ETRTO bead design — WTB states its TCS Beadlock profile is "Designed to ISO/ETRTO standards" and CZR TCS 2.0 is ETRTO/ISO compliant (source)
- CVX spoke-bed technology — Stated as patented by WTB (source)
Sources on WTB's site:
- Rim Technology - WTB
- Warranty - WTB
- Ride With Confidence Guarantee - WTB
- CZR i23 Rim - WTB
- CZR i30 Rim - WTB
WTB publishes those results; ProWheelBuilder builds the rim into a wheel and does not test it in a lab.
Building it at ProWheelBuilder
WTB makes the KOM Tough; ProWheelBuilder is an independent wheel builder in Georgia, not the manufacturer. We measure the rim before we cut a spoke, bring the wheel up in three or four rounds with a gauge, stress-relieve it between rounds and true it last, then tape it and fit a valve if you want it tubeless. TCS tape and a valve are fitted on request.
Only compatible hubs and spokes appear in the configurator, impossible combinations are struck through rather than hidden, and the price is live.
Warranty
WTB's warranty. WTB's cover depends on the rim: CZR and CGR carbon rims carry a limited lifetime warranty to the original owner, Ci24 and Ci31 carbon rims three years, and every other rim 24 months, all against defects in material and workmanship. A CZR rim broken while riding is replaced free; damage from a non-riding incident is replaced at half the current list price. Claims must be raised within 60 days of finding the defect.
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.
KOM Tough TCS I 30 Rim questions
What tire width suits this rim?
At 40mm inside this is a plus or fat width, for tires from about 2.6in upward. Running a narrow tire on a rim this wide leaves the casing stretched and vague, so match it to the tire it was designed around.
KOM Tough or KOM Light?
Same profile. Tough has thicker walls for trail and all-mountain; Light saves about 60 grams for cross-country. We stock the Tough.
What does TCS mean?
Tubeless Compatible System, WTB's bead shape that seats and holds a tubeless tire; it needs WTB TCS tape, which we fit.
Which KOM Tough width should I choose?
i25 for 2.2 to 2.4in cross-country tires, i30 for 2.4 to 2.6in trail tires, i35 for 2.6 to 2.8in, i40 for 2.8 to 3.0in plus tires.
Is the KOM Tough e-bike rated?
For light trail e-bikes with the right spokes, yes. For heavy e-MTB use WTB makes the HTZ with 20% thicker walls.
Is it tubeless-ready?
Yes. WTB lists the KOM Tough TCS I 30 Rim as clincher tubeless compatible; we tape and fit a valve when you choose the tubeless option.
Which spoke count should I choose?
It depends on your weight, terrain and the hub, not the rim alone. The configurator recommends a count from your bike type and rider weight, within the drillings this rim is made in.
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.
