Progressive Suspension 412 Series Shock 

Replaced my 11 in stock HD shocks with 12 in 412's. I don't bottom out anymore but it is a stiff ride. If you are looking for comfort, look at a different setup.

Fails to tell the view, which direction to turn the spanner adjustment and how it affects the ride.

I put a set of 11.5 inch 412s on my Triumph Thunderbird 1600. This lowered the big a good 2 inches, which is what I was looking for...lower the seat so my feet are more solid on the ground when stopping. Over all I am pleased with the look; however, the ride is a little stiffer than expected. Also, the OEM washers will not fit on the bottom part of the shock. Thunderbird riders will have to change out the washers for smallers ones. I opted for the ones on the xchoppers site. Hope this helps.

yep put these on my 04 sporty, better than standard but stiff, hope it softens up some with some more miles on it.

How to change my air shocks to spring shocks on 2014 harley trike

can i see that....how its made

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