Len Performance Front Track (Center) Shock, Ski-Doo MXZ 129 2015–2022 (54-80001F)
Len Performance Front Track (Center) Shock, Ski-Doo MXZ 129 2015–2022 (54-80001F)
Len Performance
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Most orders are ready within 24 hours. Supplier-order exceptions are confirmed by email; freight to A2D is included in the product price. Need same-day pickup? Call 907-306-3062.
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Confirm your machine’s year, model, submodel, and the selected size or option before ordering. Need help? Contact the A2D team.
Product details
Len Performance LS4-80001F rebuildable front track shock, also called the center shock, for the rear suspension on the 2015–2022 Ski-Doo MXZ 129: Sport 600 Carb / 600 ACE, and TNT, Blizzard, X, X-RS and Iron Dog with the 600 H.O. E-TEC, 600R E-TEC, 800R E-TEC, 850 E-TEC, 900 ACE and 1200 4-TEC engines. It replaces the factory front track shock with a coil-over reservoir shock. At $503.95 each, it is A2D's value pick for a rebuildable, adjustable reservoir front track shock: clicker adjustment, a reservoir and a serviceable design without the cost of a race-level shock.
The front track shock controls how the skid loads under acceleration, how the sled transfers weight and how much ski pressure you keep when you get on the throttle. Being able to adjust it, rather than living with fixed factory valving, is the single biggest change most riders feel in the rear suspension. 5-click compression adjustment and threaded preload rings let it be set for rider weight and trail conditions.
Fitment. Sold each. MXZ 129 only; not listed for the Renegade, Summit, Expedition or Lynx. Pairs with the Len Performance 54-80001R rear track shock for a complete rear suspension (Len Performance kit LS4-80001K: one LS4-80001F and one LS4-80001R). Matching ski shocks: 54-80001-1LH / RH. Platform: Ski-Doo REV-XS (2015–2016; 900 ACE / 1200 4-TEC through 2018) and REV Gen4 (2017–2022).
Fitment list (Len Performance year/model lookup)
- MXZ: 2016 MXZ 600HO E-TEC Blizzard; 2015-2018 MXZ 600HO E-TEC Iron Dog; 2017 MXZ 600HO E-TEC X; 2016 MXZ 600HO E-TEC X-RS; 2020 MXZ 600R E-TEC; 2019-2020 MXZ 600R E-TEC Iron Dog; 2019-2020 MXZ 600R E-TEC X-RS; 2016 MXZ 800R E-TEC Blizzard; 2015 MXZ 800R E-TEC Iron Dog; 2016-2018 MXZ Blizzard 1200 4-TEC 129; 2016-2018 MXZ Blizzard 600 H.O. E-TEC 129; 2019 MXZ Blizzard 600R E-TEC 129; 2016-2017 MXZ Blizzard 800R E-TEC 129; 2018-2019 MXZ Blizzard 850 E-TEC 129; 2016-2018 MXZ Blizzard 900 ACE 129; 2015-2017 MXZ Sport 600 ACE; 2015-2017 MXZ Sport 600 Carb; 2015-2018 MXZ TNT 1200 4-TEC 129; 2015-2018 MXZ TNT 600 H.O. E-TEC 129; 2019-2020 MXZ TNT 600R E-TEC 129; 2015-2017 MXZ TNT 800R E-TEC; 2018-2020 MXZ TNT 850 E-TEC 129; 2015-2018 MXZ TNT 900 ACE 129; 2015-2018 MXZ X 1200 4-TEC 129; 2015-2018 MXZ X 600 H.O. E-TEC 129; 2018-2022 MXZ X 600R E-TEC 129; 2018 MXZ X 600R E-TEC Iron Dog; 2015-2017 MXZ X 800R E-TEC 129; 2017-2022 MXZ X 850 E-TEC 129; 2015-2016 MXZ X-RS 600 H.O. E-TEC 129; 2019-2020 MXZ X-RS 600R E-TEC 129; 2015-2017 MXZ X-RS 800R E-TEC 129; 2018-2020 MXZ X-RS 850 E-TEC 129; 2017-2018 MXZ X-RS Iron Dog 600 H.O. E-TEC 129
Features
- 5-click compression adjustment, tool-free.
- Aluminum reservoir shock: the remote-style reservoir keeps oil temperature down and damping consistent on long pulls.
- Fully rebuildable, serviceable shock. Len Performance rebuild kits and replacement parts are available.
- Hardened chromoly shaft for strength and seal life.
- Forged aluminum eyelet heads with premium steel and NBR bushings.
- Powder-coated spring resists corrosion and holds rate in cold, wet conditions.
- Threaded shock body with anodized dual-ring locking preload adjusters: set sag once and it stays set.
- Sold each.
Specifications
| Part number | 54-80001F (Len Performance LS4-80001F) |
| OEM part number replaced | 503193283 (per distributor listings) |
| Shock location | Front track shock / center shock (rear suspension) |
| Chassis / platform | Ski-Doo REV-XS / REV Gen4, MXZ 129 |
| Adjustments | Compression (5), plus threaded spring preload |
| Length, extended | 365 mm / 14.4 in |
| Length, compressed | 251 mm / 9.9 in |
| Stroke | 114 mm / 4.5 in |
| Spring | Powder-coated coil spring included, 77.4 mm / 3.0 in diameter |
| Top eyelet | 12.5 mm ID x 25.2 mm wide (0.5 in x 1.0 in) |
| Bottom eyelet | 10.1 mm ID x 29.5 mm wide (0.4 in x 1.2 in) |
| Weight | 5.85 lb (8 lb shipping) |
| Includes | One shock |
| Rebuild kit | 54-00004 (Len LSR-00004), per Dennis Kirk |
| Sold | Each |
Ordering and installation. Sold each. Ships from stock at our Anchorage shop, or from our distributor's Boise, Idaho warehouse when not on the shelf. In-store pickup is available at checkout. Installation and shock setup are available at A2D Motorsports; call (907) 306-3062 to schedule. Len Performance rebuild kits are available, so the shock can be serviced or re-valved rather than replaced.