I don't know how much you know about suspension components, so if this is "DUH, I Know that", then please forgive this.
The preload may be set too high. Do you know you can unscrew the shock (spring) to lessen the pre-load?
If you look at the shock body, you'll notice one side is threaded. The retaining clip on that side of the spring is also threaded. You can grab a hold of the spring and turn it to loosen or tighten the pre-load.
L8R
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