SE Bikes Rear Solid Axle – 3/8" Cr-Mo – 142mm Hub / 210mm Length – Beast Mode Ripper (2018–2023) / Monster Ripper & Monster Quad (2019–2023)
This is a direct replacement rear solid axle for specific 29" and 27.5"+ SE Bikes models using a 142mm rear hub spacing. It fits select Beast Mode Ripper, Monster Ripper, and Monster Quad model years.
This is the axle shaft only. No nuts, washers, cones, or spacers included. Confirm hub spacing and model year before ordering.
Key Functional Details
- 3/8" solid rear axle
- Chromoly (Cr-Mo) construction
- 142mm rear hub spacing (OLD)
- 210mm overall axle length
- Rear hub application
- Axle shaft only – hardware not included
- Platform: BMX (29" / 27.5"+ street BMX specific)
Compatibility & Technical Notes
- Fits MY18–MY23 SE Beast Mode Ripper (142mm rear hub versions)
- Fits MY19–MY23 SE Monster Ripper (142mm rear hub versions)
- Fits MY19–MY23 SE Monster Quad (142mm rear hub versions)
- Requires 3/8" solid axle rear hub
- Hub spacing (OLD): 142mm
- Overall axle length: 210mm
- Does NOT fit 170mm fat bike hubs
- Does NOT fit 190mm or 197mm fat bike hubs
- Does NOT fit 14mm BMX hubs
- Does NOT fit 12mm thru-axle MTB systems
- Does NOT fit quick-release hubs
- Confirm your model year and hub spacing before purchase
- Platform Type: BMX (29" / 27.5"+ models listed only)
Service / Ownership Context
Solid rear axles commonly bend on wheelie bikes and large-wheel BMX models from heavy landings or repeated torque loads. Replacement requires full hub disassembly and correct bearing preload adjustment. This is a service-level repair for most riders.
Fit & Use Signals
- Good Fit: You own a 2018–2023 Beast Mode Ripper with 142mm rear hub spacing.
- Good Fit: You own a 2019–2023 Monster Ripper or Monster Quad with 142mm rear hub spacing.
- Good Fit: Your current axle measures approximately 210mm overall.
- Not A Fit: You have a Fat Ripper or Fat Quad (170mm spacing).
- Not A Fit: Your hub uses a 14mm BMX axle.
- Not A Fit: Your bike uses a thru-axle system.
These bend from hard wheelies, heavy riders, or repeated curb drops. Beast Mode and Monster bikes get ridden hard. Most customers don’t measure OLD (Over Locknut Dimension). 142mm is not the same as fat spacing. If they guess, they buy wrong. If axle is bent, inspect cones and bearing surfaces. Sometimes the cone threads get damaged. Axle only — no hardware. People forget this. If rider keeps bending axles, consider whether frame allows 14mm upgrade. Many of these frames are built around 3/8” only. Common complaint: “It bent again.” That’s riding style, not axle defect. Install requires hub teardown and proper cone preload. Over-tightening kills bearings fast.