The Krumbein is American Classic's most aggressive gravel tire ideal for gravel roads, loose trails, and fast singletrack. The all-weather design includes tall side lugs for cornering grip on loose and rocky conditions, chamfered center knobs minimize rolling resistance, and there is plenty of space between knobs to prevent mud build-up. Combined with our signature Rubberforce G tread compounds and Stage 5S Armor construction, this tire provides impressive grip in the dirt and improves both ride quality and abrasion resistance compared to its predecessor.
- Fast and efficient tire from loose gravel to single track
- 700x40C, 700x50C, 650Bx47
- Tubeless Ready
- Stage 5S Armor construction
- Rubberforce G gravel tire compound
- Chamfered center tread minimizes rolling resistance
- Black, tan, or brown sidewall
|Protection||Stage 5S Armor|
|Size Options||700x40C (ETRTO 40-622)|
Weight: 540-545 g
Max Pressure: 55 PSI
700x50C (ETRTO 50-622)
Weight: 670-680 g
Max Pressure: 50 PSI
650Bx47mm (ETRTO 50-584)
Weight: 625-630 g
Max Pressure: 50 PSI
Road Hazard Replacement Program
American Classic stands by our tires, and want to keep our customers rolling. Our Road Hazard Replacement Program offers our customers the promise that if you puncture or tear an American Classic tire while riding, and it no longer holds air, you can contact us for a claim form for a one-time 50% off the MSRP of the same or comparable product. The replacement program covers American Classic products purchased through authorized dealers, www.amclassic.com, or the American Classic branded Amazon store, and product included as original equipment components of a new bicycle purchase. The Road Hazard Replacement Program does not include shipping and handling. This program is currently available to residents of the United States and the following territories: Puerto Rico, Virgin Islands.
American Classic tires have a 2-year warranty against defects in materials and workmanship. Any defective tires will be replaced at no charge. This warranty applies to the original owner with proof of purchase and is non-transferable and non-assignable. The original owner is responsible for all postage costs and transportation risks of the returned product(s). The warranty covers American Classic products purchased through authorized dealers, www.amclassic.com, or the American Classic branded Amazon store, and product included as original equipment components of a new bicycle purchase. The warranty does not cover normal wear and tear, product abuse, commercial usage, shipping damage, improper installation and/or maintenance, negligence, reckless handling, and/or unauthorized modification.
Please contact firstname.lastname@example.org for warranty information and claim forms.
Some American Classic tires are compatible with hookless (Tubeless Straight-Side/TSS) rims. To be compatible, the following must be met:
- The tire must be included in the approved section below,
- The rim must meet current E.T.R.T.O. standards for tubeless systems, and
- The tire must be placed on an appropriate width rim.
More information on hookless compatibility can be found on our Tire and Rim Compatibility page.
Approved for use:
- Aggregate TLR
- Kimberlite TLR
- Krumbein TLR
- Udden TLR
- Wentworth TLR
- Tectonite TLR
- Basanite TLR
- Vulcanite TLR
- Mauka TLR
- Timekeeper TLR with Stage 3S Armor
- Torchbearer TLR with Stage 4S Armor
- Lamplighter (all versions)
- Timekeeper Tube-Type (all versions)
- Timekeeper TLR with Stage 3 Flat Protection
- Torchbearer Tube-Type (all versions)
- Torchbearer TLR with Stage 3S Flat Protection
This list will be updated as additional tire models are introduced.