Technical Details
Build Specs
| Shimano GRX 600 | SRAM Apex Mechanical | Custom Bike Builder | |
| Frame | Otso custom butted 4130 Chromoly tubing with Tuning Chip™️ dropout system | Otso custom butted 4130 Chromoly tubing with Tuning Chip™️ dropout system | Otso custom butted 4130 Chromoly tubing with Tuning Chip™️ dropout system |
| Fork | Lithic full carbon fork, 12mm thru-axle, triple mounts | Lithic full carbon fork, 12mm thru-axle, triple mounts | Lithic full carbon fork, 12mm thru-axle, triple mounts |
| Headset | FSA Orbit ITA Headset, black | Wolf Tooth Headset, custom colors | Wolf Tooth Headset, custom colors |
| Drivetrain | Shimano GRX 600 1x12 mechanical | SRAM Apex 1x12 mechanical | Custom Options: • Shimano GRX 600 1x12 mechanical • Shimano GRX 800 Di2 1x12 electronic • SRAM Rival/GX AXS Mullet 1x12 electronic • SRAM Force XPLR AXS 1x12 electronic |
| Rear derailleur | Shimano GRX 822, 12-speed, RD-RX822 | Apex Eagle D1 | • Shimano GRX 600: RD-RX822 • Shimano GRX 800 Di2: RD-RX827 • SRAM Rival/GX AXS Mullet: GX Eagle AXS • SRAM Force XPLR AXS D2, Unicorn Gray |
| Front derailleur | n/a | n/a | n/a |
| Shifters | Shimano GRX 610, BL-RX610 | Apex D1 | • Shimano GRX 600: RD-RX822 • Shimano GRX 800 Di2: RD-RX827 • SRAM Rival/GX AXS Mullet: Rival E1 • SRAM Force XPLR AXS: Force E1 |
| Cassette | Shimano SLX, 10-51T, 12-speed, CS-M7100 | PG1230 Eagle 11-50T (HG) | • Shimano GRX 600: SLX M7100 10-51T • Shimano GRX 800 Di2: XT M8100 10-51T • SRAM Rival/GX AXS Mullet: NX PG-1230-A1 11-50T • SRAM Force XPLR AXS: XG-1251 10-44T |
| Brakes | Shimano GRX 410 Hydraulic, BR-RX410 | Apex D1 | • Shimano GRX 600: BR-RX410 • Shimano GRX 800 Di2: BR-RX820 • SRAM Rival/GX AXS Mullet: Rival E1 • SRAM Force XPLR AXS: Force E1 |
| Cranks | Shimano GRX 610 with 40T chainring, FC-RX610-1, length scaled with frame size: 165mm for 49cm frames, 170mm for 52cm and 54cm frames, 172.5mm for 56cm and 58cm frames, 175mm 60cm frames | Apex with 42T chainring, 170mm; road wide | • Shimano GRX 600: FC-RX810, 170mm • Shimano GRX 800 Di2: FC-RX810, 170mm • SRAM Rival/GX AXS Mullet: Rival E1, 170mm • SRAM Force XPLR AXS: Force E1, 170mm |
| Bottom bracket | Shimano English threaded BSA, 68mm, SM-BBR60 | SRAM DUB English/BSA Road Wide 68mm | • Shimano GRX 600: SM-BBR60 • Shimano GRX 800 Di2: SM-BBR60 • SRAM Rival/GX AXS Mullet: SRAM DUB BSA Road Wide 68mm • SRAM Force XPLR AXS: SRAM DUB BSA Road Wide 68mm |
| Handlebar | Lithic Aventurine; 16 deg flare, 5 deg sweep, 120mm drop, 70mm reach; scaled with frame size: 40cm bars for 49cm frames, 42cm bars for 52cm frames, 44cm bars for 54cm and 56cm frames, 46cm bars for 58cm and 60cm frames | custom options | custom options |
| Handlebar tape | Anti-Slip Gel Bar Tape | Anti-Slip Gel Bar Tape | Anti-Slip Gel Bar Tape |
| Stem | Aluminum; black; length scaled with frame size: 50mm for 49cm, 60mm for 52cm, 70mm for 54cm, 80mm for 56cm, 90mm for 58cm, 100mm for 60cm | custom options | custom options |
| Seatpost | 27.2x350mm; 6061 aluminum; black | custom options | custom options |
| Seatpost Clamp | 29.8mm; CNC aluminum; black | Wolf Tooth 29.8, custom colors | Wolf Tooth 29.8, custom colors |
| Saddle | WTB Silverado Medium; Steel; 142x265mm | WTB Silverado Medium; Steel; 142x265mm | WTB Silverado Medium; Steel; 142x265mm |
| Wheels | Hayes Duroc 30 Comp: 650b for 49cm frame; 700c for 52cm-60cm frames | Base build price includes DT Swiss G 1800; custom 700c options for sizes 52cm-60cm, custom 650b options for 49cm | Base build price includes DT Swiss G 1800; custom 700c options for sizes 52cm-60cm, custom 650b options for 49cm |
| Tires | Schwalbe G-One Allround Perf, RaceGuard, TLR, 650x40 for 49cm frame; Schwalbe G-One RS Performance, RaceGuard, TLR; 45mm for 52-60cm frames; black | custom options | custom options |
| Chain | Shimano SLX 12-speed, CN-M7100 | SRAM NX Eagle 12-speed | • Shimano GRX 600: Shimano SLX 12-speed • Shimano GRX 800 Di2: Shimano SLX 12-speed • SRAM Rival/GX AXS Mullet: SRAM Rival 12-speed flat top • SRAM Force XPLR AXS: SRAM Rival 12-speed flat top |
Frame Specs
| Sizes 52cm-60cm | Size 49cm | |
| Bottom bracket standard | 68mm BSA threaded | 68mm BSA threaded |
| Q factor | 146mm with Shimano RS510 crankset | 146mm with Shimano RS510 crankset |
| Maximum chainring size | 2x: 53T round / 31T round; 1x: 50T round or 46T oval | 1x only, 46T round or 44T oval |
| Minimum Chainline | 47.5mm | 47.5mm |
| Front derailleur type | 28.6mm clamp, bottom pull | not compatible, 1x only |
| Headset | ZS44/28.6 upper, EC44/40.0 lower | ZS44/28.6 upper, EC44/40.0 lower |
| Seatpost diameter | Ø27.2mm | Ø27.2mm |
| Internal dropper post routing | Yes, exit port on bottom of seat tube | Yes, exit port on bottom of seat tube |
| Seatpost clamp | Ø29.8mm | Ø29.8mm |
| Front/rear hub standard | 100x12mm thru axle / 142x12mm thru axle | 100x12mm thru axle / 142x12mm thru axle |
| Front/rear axle | Ø12x125mm front, TP=1.5, TL=12mm / Ø12x180mm rear, TP=1.5, TL=12mm | Ø12x125mm front, TP=1.5, TL=15mm / Ø12x180mm rear, TP=1.5, TL=12mm |
| Derailleur hanger | Wolf Tooth Tuning Chip Right Dropout | Wolf Tooth Tuning Chip Right Dropout |
| Rear brake (rotor) | Flat mount, 74mm post mount available(160mm) | Flat mount, 74mm post mount available(160mm) |
| Front brake (rotor) | Flat mount native, 74mm post mount adapter available (160mm) | Flat mount native, 74mm post mount adapter available (160mm) |
| Fork axle-to-crown | 420mm, suspension corrected up to 40mm travel | 420mm, suspension corrected up to 40mm travel |
| Fork offset | 47mm | 47mm |
| Bare frame weight | 5.53 lbs / 2509 g (size 56cm) | 5.02 lbs / 2275g (size 49cm) |
| Fork weight (Lithic Hiili) | 490 g | 490 g |
| Tire clearance (frame) | 700c & 650b x 40mm at 420mm chainstay position; 700c & 650b x 50mm at 430/440mm chainstay positions | 650b x 40mm at 410mm chainstay position; 650b x 50mm at 420/430mm chainstay positions; *700c not recommended* |
| Tire clearance (fork) | Max clearance 29" x 2.1" (54-622) | Max clearance 29" x 2.1" (54-622) |
| Braze-ons | Three bottle frame mounts, fender, rack, cable clamps, two three-pack mounts on fork | Three bottle frame mounts, fender, rack, cable clamps, two three-pack mounts on fork |
| Seatpost Insertion Depth | 52cm: 310mm; 54cm: 290mm; 56cm: 290mm; 58cm: 310mm; 60cm: 330mm | 49cm: 230mm |
| Max weight (rider + gear) | 275 lbs. | 275 lbs. |
| Max spacer stack under stem | 40mm | 40mm |
| Max spacer stack above stem | 10mm | 10mm |
| Max stem bolt torque | 6 Nm | 6 Nm |
| Frame Bag Dimensions | 52cm 54cm 56cm 58cm 60cm | 49cm |
Geometry
| 49cm | 52cm | 54cm | 56cm | 58cm | 60m | |
| Recommended rider height | 4'11"-5'2" | 5'2"-5'4" | 5'4"-5'8" | 5'8"-6'0" | 6'0"-6'2" | 6'2"-6'5" |
| Recommended rider inseam | 25"-29" | 28"-30" | 30"-33" | 32"-34" | 33"-35" | 34"-37" |
| Effective top tube | 510mm | 530mm | 545mm | 565mm | 580mm | 600mm |
| Nominal head tube angle | 70° | 70.5° | 71° | 71.5° | 72° | 72° |
| Tuning Chip-induced head/seat tube angle change from middle position | ±0.25° | ±0.25° | ±0.25° | ±0.25° | ±0.25° | ±0.25° |
| Head tube length | 87mm | 95mm | 115mm | 140mm | 165mm | 185mm |
| Nominal seat tube angle | 75° | 74.5° | 74° | 73° | 72.5° | 72° |
| Seat tube length | 400mm | 505mm | 530mm | 550mm | 570mm | 590mm |
| Bottom bracket drop | 58-62mm | 68-72mm | 68-72mm | 68-72mm | 68-72mm | 68-72mm |
| Chainstay length | 410-430mm | 420-440mm | 420-440mm | 420-440mm | 420-440mm | 420-440mm |
| Wheelbase | 1000-1020mm | 1017-1037mm | 1023-1043mm | 1028-1048mm | 1032-1052mm | 1046-1066mm |
| Trail | 70mm | 71mm | 70mm | 67.5mm | 65mm | 65mm |
| Fork offset | 47mm | 47mm | 47mm | 47mm | 47mm | 47mm |
| Rigid fork axle to crown length | 420mm | 420mm | 420mm | 420mm | 420mm | 420mm |
| Stack | 532mm | 549mm | 570mm | 596mm | 622mm | 641mm |
| Reach | 368mm | 378mm | 381mm | 383mm | 384mm | 392mm |
| Standover | 677mm | 760mm | 780mm | 800mm | 820mm | 840 mm |