IRC GP-21 / GP-22: sizes and matching bikes
Type: Trail ／ Street legal
About this tire
GP-21 front, GP-22 rear. IRC calls it an all-rounder “covering the range of surfaces you expect on a forest-road tour.”
Across the six axes, Pavement・Life sits at 4 and Sand・Mud・Rocks at 2. Neither extreme nor flat. Of the 18 tires in the Trail group, 9 carry 4 for Pavement. 5 front sizes and 7 rear, mostly 17-inch.
Our rating (1–5)
| Sand | 2 / 5 |
|---|---|
| Mud | 2 / 5 |
| Rocks | 2 / 5 |
| Hard-pack | 3 / 5 |
| Pavement | 4 / 5 |
| Life | 4 / 5 |
OE sizes can differ by model year and market — the sidewall of your own bike is the sure reference. This is a Japanese-market lineup; the sizes themselves are international.
Size lineup
Front
- 110/80-17
- 70/100-19
- 2.75-21
- 3.00-21
- 80/100-21
Rear
- 120/90-16
- 90/100-16
- 130/80-17
- 140/70-17
- 4.60-17
- 120/80-18
- 4.10-18
Bikes whose OE sizes it fits
Of the 260 bikes on file, this tire’s size lineup fits the OE sizes of 70. Each link opens the tires you can pick for that bike.
| Model | Years | Front | Rear |
|---|---|---|---|
| BMW F 450 GS | 2026–present | 100/90-19 | 130/80-17 |
| BMW F 900 GS | 2024–present | 90/90-21 | 150/70R17 |
| BMW R 12 G/S | 2025–present | 90/90-21 | 150/70R17 |
| KTM 85 SX 19/16 | 2020–26 | 70/100-19 | 90/100-16 |
| KTM 125 ENDURO R / 390 ENDURO R | 2025 model | 90/90R21 | 140/80R18 |
| KTM 125 SX / 150 SX | 2020–26 | 80/100-21 | 100/90-19 |
| KTM 125 XC / 250 XC / 250 XC-F / 350 XC-F / 450 XC-F | 2020–26 | 80/100-21 | 110/100-18 |
| KTM 150 EXC TPI / 150 XC-W | 2020–26 | 80/100-21 | 110/100-18 |
| KTM 250 EXC TPI | 2020–22 | 80/100-21 | 140/80-18 |
| KTM 250 EXC-F | 2020 model | 80/100-21 | 140/80-18 |
| KTM 250 EXC-F | 2025–26 | 90/90-21 | 140/80-18 |
| KTM 250 SX / 300 SX | 2020–26 | 80/100-21 | 110/90-19 |
| KTM 250 SX-F | 2020–26 | 80/100-21 | 110/90-19 |
| KTM 250 XC-W / 300 EXC (formerly XC-W TPI) | 2026 model | 90/90-21 | 140/80-18 |
| KTM 300 EXC TPI | 2020 model | 80/100-21 | 140/80-18 |
| KTM 350 EXC-F | 2020 model | 80/100-21 | 140/80-18 |
| KTM 350 EXC-F | 2025–26 | 90/90-21 | 140/80-18 |
| KTM 350 SX-F | 2026 model | 80/100-21 | 110/90-19 |
| KTM 390 ADVENTURE R | 2025 model | 90/90-21 | 140/80-18 |
| KTM 390 ADVENTURE X | 2025 model | 100/90-19 | 130/80-17 |
| KTM 450 EXC-F | 2020 model | 80/100-21 | 140/80-18 |
| KTM 450 EXC-F | 2025–26 | 90/90-21 | 140/80-18 |
| KTM 450 SX-F | 2020–26 | 80/100-21 | 110/90-19 |
| KTM 500 EXC-F | 2020 model | 80/100-21 | 140/80-18 |
| KTM 500 EXC-F | 2025 model | 90/90-21 | 140/80-18 |
| KTM 690 ENDURO R | 2026 model | 90/90-21 | 140/80-18 |
| KTM 790 ADVENTURE / R | 2025–26 models | 90/90-21 | 150/70R18 |
| KTM 890 ADVENTURE R | 2025–26 models | 90/90B21 | 150/70B18 |
| KTM 1390 SUPER ADVENTURE R | 2026 model | 90/90ZR21 | 150/70ZR18 |
| Kawasaki KLX140R L | 2027 model | 70/100-19 | 90/100-16 |
| Kawasaki KLX230 / S | 2024–present | 2.75-21 | 4.10-18 |
| Kawasaki KLX230 DF | 2026 model | 2.75-21 | 4.10-18 |
| Kawasaki KLX230 SHERPA S | 2025–present | 2.75-21 | 4.10-18 |
| Kawasaki KLX230R / R S | 2027 model | 80/100-21 | 100/100-18 |
| Kawasaki KX112 | 2022 model | 70/100-19 | 90/100-16 |
| Kawasaki KX250F | 2027 model | 80/100-21 | 110/90-19 |
| Kawasaki KX250FX | 2027 model | 80/100-21 | 110/100-18 |
| Kawasaki KX450 | 2020 model | 80/100-21 | 120/80-19 |
| Suzuki DR-Z4S | 2025–present | 80/100-21 | 120/80-18 |
| Suzuki RM-Z250 | 2020 model | 80/100-21 | 100/90-19 |
| Suzuki RM-Z450 | 2020 model | 80/100-21 | 110/90-19 |
| Suzuki V-Strom 250SX | 2023–present | 100/90-19 | 140/70-17 |
| Suzuki V-Strom 800DE | 2023–present | 90/90-21 | 150/70R17 |
| Suzuki V-Strom 1050DE | 2023–present | 90/90-21 | 150/70R17 |
| Ducati DesertX / Discovery | 2022–present | 90/90-21 | 150/70R18 |
| Ducati DesertX Rally | 2024–present | 90/90-21 | 150/70R18 |
| Triumph Scrambler 1200 X / XE | 2024–present | 90/90-21 | 150/70R17 |
| Triumph TF 250-E / TF 450-E | current as of Aug 2026 | 90/90-21 | 140/80-18 |
| Triumph TF 450-RC Edition | 2025 model | 80/100-21 | 110/90-19 |
| Triumph Tiger 900 Rally Pro | current as of Aug 2026 | 90/90-21 | 150/70R17 |
| Triumph Tiger 1200 Rally Pro / Rally Explorer | current as of Aug 2026 | 90/90-21 | 150/70R18 |
| Honda CRF250 RALLY | 2020–present | 80/100-21 | 120/80-18 |
| Honda CRF250L / L〈s〉 (low-seat) | 2020–present | 80/100-21 | 120/80-18 |
| Honda CRF250R | 2020 model | 80/100-21 | 100/90-19 |
| Honda CRF250RX | 2020 model | 80/100-21 | 110/100-18 |
| Honda CRF450R | 2020 model | 80/100-21 | 120/80-19 |
| Honda CRF450RX | 2020 model | 90/90-21 | 120/90-18 |
| Honda CRF1100L Africa Twin | 2020 model | 90/90-21 | 150/70R18 |
| Honda XL750 Transalp (incl. E-Clutch) | 2026 model | 90/90-21 | 150/70R18 |
| Yamaha WR125R | 2026–present | 2.75-21 | 4.10-18 |
| Yamaha YZ85LW (19/16) | 2001–present | 70/100-19 | 90/100-16 |
| Yamaha YZ125 | 2001–present | 80/100-21 | 100/90-19 |
| Yamaha YZ125X / YZ250X | 2022–present | 80/100-21 | 110/100-18 |
| Yamaha YZ250 (2-stroke) | 2001–present | 80/100-21 | 110/90-19 |
| Yamaha YZ250F | 2021–present | 80/100-21 | 110/90-19 |
| Yamaha YZ250FX | 2019–present | 80/100-21 | 110/100-18 |
| Yamaha YZ450F | 2019–present | 80/100-21 | 120/80-19 |
| Yamaha YZ450FX | 2018–present | 80/100-21 | 120/90-18 |
| Yamaha Serow 250 (Final Edition) | to 2020 | 2.75-21 | 120/80-18 |
| Yamaha Ténéré 700 | 2020–present | 90/90-21 | 150/70R18 |
Where to buy
How to read this
- The 1–5 ratings are our own estimates. Not manufacturer figures, not measurements.
- Within one model, character and street legality both change with the size and the spec. Confirm with the manufacturer or a dealer before you buy.
- Shop links go to search results rather than product pages. Other sizes and older models will be mixed in.
- “Narrower” means one or two steps below the OE size. The “rim width OK” badge means the tire maker's published rim widths line up with the OE rim width; no badge means unconfirmed.
- Competition tires may not be used on public roads.