Kawasaki Z400 mods & upgrades

The Z400 is the Ninja 400 with a one-piece bar 50 mm higher and springs about 10 percent lighter, so Ninja 400 engine, chassis and exhaust parts carry over. Start with protection, a slip-on and springs matched to your weight.

1. Tail tidy

   Fit a fender eliminator. Yoshimura's V2 kit covers Ninja 400 2018–23 and Z400 2019–23 in one SKU, and TST's Elite-1 low-mount kit names the Z400. New Rage Cycles lists a Ninja 400 (2018–24) kit only.

   Tail Tidy & Billet

2. Sliders and spools

   Add frame sliders and swingarm spools. GB Racing's Ninja 400/Z400 page lists bullet frame sliders and secondary engine covers, TST lists fork sliders for the Z400, and Kawasaki sells 8 mm spools (012BOY0013).

   Crash Protection

3. Slip-on exhaust

   Slip-ons exist: Kawasaki lists an Akrapovič slip-on (item 124878) on its 2019–21 Z400 pages, and Two Brothers, Coffman's, Yoshimura and LeoVince list one for the Z400 or Ninja 400. Check which Akrapovič version you are buying; its carbon slip-on carries a street-emissions warning.

   Exhaust

4. Springs for your weight

   Kawasaki fitted springs about 10 percent lighter than the Ninja 400's. Fit fork springs and a shock spring for your weight; YSS lists Z400 shocks for 2018–19 and Nitron lists a Z400 fork cartridge kit.

   Suspension

5. Tank grips and meter cover

   Stompgrip lists one tank-grip set for the Ninja 650, Z400 and Z650 2017–26. Kawasaki's only wind accessory for the Z400 is the Meter Cover (99994-1128).

   Clip-ons & ThrottleBodywork

1. Tires

   Fit sport or race tires in 110/70-17 and 150/60-17; the OE tire is a Dunlop Sportmax GPR-300. Add tire warmers only once your lap times are consistent.

   Tires & Wheels

2. Suspension for your weight

   Fit springs and oil for your weight, not the Ninja 400's numbers, then a better shock. Rider reports the Z400's fork and shock match the Ninja 400's apart from the springs, so Ninja 400 kits apply: Traxxion lists an AK-20 cartridge kit and a YSS shock, and TST sells Andreani's Misano EVO2 cartridges.

   Suspension

3. Pads, line, fluid

   Fit sintered pads (EBC lists HH pads for the Z400 ABS, 2018–21), a braided line and fresh fluid.

   Brakes

4. Make it crashable

   Fit engine covers and, if your organization requires one, a lever guard. GB Racing lists covers and sliders for the Ninja 400/Z400, and Norton Racing sells rearset risers for the Ninja 400's OEM rearsets (2018–23); confirm each listing fits the Z400.

   Crash ProtectionRearsetsLevers

5. Gearing, then a flash

   Change sprockets first: stock is 14/41 on a 520 chain, and a tooth fewer on the front or two more on the rear shortens the gearing. A full system plus a flash is the last step; Woolich lists the Z400 for 2018–24 and FTECU sells Z400 data-link kits for 2018–22 and 2021–24, both for closed-course use.

   DrivetrainExhaustTune

• ER400D2019–2023

  One generation: the Ninja 400's 399 cc twin and trellis frame with a one-piece bar 50 mm higher, springs about 10 percent lighter front and rear, and Z bodywork. Sold in the US as the Z400 ABS only; $4,799 at launch and $5,399 for 2023. Kawasaki lists the same fork, shock, tires and 363.8 lb curb weight for 2020, 2021 and 2023, so 2019 listings generally fit 2023 (verify with the seller).

• Z500 (successor)2024–present

  Not a Z400: a 451 cc stroked twin (70.0 × 58.6 mm) with a claimed 51 hp, an LCD dash (TFT on the SE) and a 2026 price of $5,699. Kawasaki lists the same fork, tires, front disc and seat height as the Z400, but a horizontal back-link rear suspension where the Z400 uses bottom-link Uni-Trak. Some vendors list parts for both bikes; confirm the listing names the 500.