Vintage Dirt Bike Q & A

I am restoring a 1980 cr250. All is going well and the motor is running good. My question is about the rear shocks. Unfortunately I don't have the operating manual but I've read in other places the rear shocks have a hard and soft damping adjustment and the rider can set hard or soft by twisting the shock shaft. Does anyone know how this is done? Is there a special tool involved? It seems the spring would prevent any adjustment.
Thanks.

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80 CR250Ra
80 CR250Ra
78 CR250R
80 CR80
82 Bultaco Sherpa 340
78 Bultaco Pursang 250 MK12
76 Bultaco Frontera 370 MK10
76 Bultaco Alpina 250
73 Bultaco Lobito 125 MK6
76 Suzuki RM125A
90 Kawasaki KX250

Thanks!