I completely understand the difference and that the shocks
should be valved differently. I am just not convinced that they
actually are from Arctic Cat... even though the 2-strokes use different springs than the 4-stroke in some situations.
For instance, see the link below for a center shock used on the 137 & 146 sleds.
You will notice this... it's a mixed bag of 2-stroke & 4-stroke Procross sleds AND Catalyst 600 & 858 sleds... ALL using the same 1704-236 spring in this example (the standard 90/250 spring that comes on 137 Sidewinder center shocks).
Fits the following 129"-146" models with the addition of a 1704-736 spring:
2015-2025 Pantera 6000, 7000 146"
2020 Riot X 8000 146"
2020-2025 Riot 600, 6000, 8000, 858, 9000 146"
2017-2025 ZR 6000, 7000, 8000, 9000 137"
2024-2025 ZR 600 Catalyst 129", 137"
2025 ZR 858 Catalyst 129", 137"
(Excludes 129" ProCross Chassis models)