I have been wanting to do this for quite sometime as chassis lengths are important to how your motorcycle reacts on the track. Sometimes we just go about our day, slap a different size sprocket on or cut our new chain a different length. However, when you do that it can/does affect how your bike rides on the track. Usually race teams are locked in on a specific setting but in the real world we ride our bikes a lot longer before changing chains/sprockets/fork heights/etc. so I worked on getting you all a variance to be within. These specs below keep the most stability without sacrificing corners stability that each bike gives in stock form. All of these numbers are with stock offset and stock gearing (recommended fork height with these measurements are also next to each bike) If there was a gearing change that I felt like may benefit needed on a certain brand those lengths are next to the sprocket size.
2026 Kawasaki KX250: Stock Gearing (fork height 2mm)
Wheelbase: 1483-1487mm
Swingarm Length: 585-588mm
2026 Kawasaki KX250: 13/51 Gearing (fork height 2mm)
Wheelbase: 1486-1489mm
Swingarm Length: 586-590mm
2026 Honda CRF250R: Stock Gearing (fork height flush-2mm)
Wheelbase: 1485-1490mm
Swingarm Length: 582-585mm
2026 Yamaha YZ250F: 13/49 Gearing (fork height flush)
Wheelbase: 1482-1490mm
Swingarm Length: 580-588mm
2026 KTM 250 SX-F: Stock Gearing (fork height 3mm)
Wheelbase: 1490-1493mm
Swingarm Length: 595-598mm
2026 Suzuki RM-Z250: Stock Gearing (fork height 3mm)
Wheelbase: 1485-1488mm
Swingarm Length: 584-586mm
2026 Triumph TF250-X: 13/49 Gearing (fork height 3mm)
Wheelbase: 1502-1504mm
Swingarm Length: 593-596mm
