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Overview of Performance Rear Shocks

Price: $0.02
  • Item #: R-SHK-FAQ
  • Manufacturer: DK Custom Products
  • Condition: New
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Rear Shocks Testing Report





How We Tested:

Everyone’s perception of what is a good ride can vary.  So we employed the butts of more than a few folks.

We spent over 1 year and more than 25,000 miles testing a wide array of rear shocks.  We also we spent time testing various shocks on a Shock Dynamometer, measuring compression, rebound, spring rates and travel.



We used 2 Sportsters, 2 Dynas, a Street Glide, an Electra-Glide, and 2 Tri-Glides.


We ran solo, 2-up, & loaded down with luggage.


Our focus was on how it felt, and how it handled in a variety of situations-

We have two “courses” that we ran through, slowly, at cruising speed, and fast.  We also did several longer trips, ranging from 800 miles to 3,000 miles, both 1 up and 2 up.

Another aspect of the testing is that when you go from one shock to another, you will notice some differences, but many times, when you go Back to the previous shock, you will pick up even more differences.  Because of that, we tested each pair of shocks multiple times, before and after other shocks in the test.

Specific Ride Compliance Testing Strategies-

Riding two circuits, with straights, curves, smooth & bumpy surfaces.  We rode thru the same curves & over the same bumps & dips under acceleration, cruising and braking conditions... 1 up, 2 up and loaded.


On 2 wheeled bikes we paid close attention to “wallowing”, and on the Trikes we paid close attention to body roll, testing for stability in curves.  For us it is important to be able to go as fast thru a curve as you want without having wallow or body roll being a limiting factor.  What this translates to, in daily riding, is better control/safer operation in the curves, even at normal speeds.


Another safety factor we tested for was rear tire/tires skidding when braking hard  on roads that were not smooth.  The better a shock functions, the better it stays in contact with the road, reducing the possibility of the rear tire/tires “locking up” when going over an imperfect surface.  This is not particularly needed in everyday riding, but when it is time to do an emergency stop, it can make all the difference.


One of the most important things we looked for in our testing was to make the small road imperfection disappear and to take all the harsh jolts and "round the edges", making them seem more like a small dip.




What we Tested


We tested over 2 dozen different shocks, including all the popular brands/models.  We test 11’, 12’, 13” & 14” shocks.


We made the decision to not list the products we tested that produced less than favorable results, nor have we listed the products that were very expensive and produced results not significantly better than less expensive options.


We have included a few of the more popular model shocks to give a point of reference when comparing.



Test Results


In all our testing, the stock shocks was consistently the least favourable.  



On the Sportster and Dyna the Twin Adjustable Bitubo and the Pro-Actions Street Series shocks were the best by a significant margin over shocks of similar and even higher price.






On the Touring Models the Twin Adjustable Bitubo and the Pro-Actions Street Series shocks were again tied.  


However the Pro-Action/DK Custom Max-Travel™ 14” Shocks were significantly better when riding 2 up, 300 lbs+ 1 up, or even sub 300 lbs 1 up when it was a road with significant bumps.  


The only time when these 14” shocks were not better than the 13” Twin Adjustable or 13” Pro-Action is when it was with a 150-275 lbs rider on roads with no big bumps.


For 2 up riding and heavier solo riders, the extra travel in the 14” shocks makes for a very noticeable improvement over the 13”.


Important Note:  The 14” Modified shocks require the use of a 1” Lowering Block to keep the ride height the same as stock.  There are a few Touring Models that cannot utilize Lowering Blocks because of bag clearance issues.  You can check fitment at this LINK.




On the Trikes the Twin Adjustable Bitubo and the Pro-Actions Street Series shocks were tied, providing a significantly better ride quality than other shocks of similar and higher price.  


However, the 14” Trike Series Shocks were the better, in every instance.  These are the first shocks that have been designed and built, from the ground up, for a Harley-Davidson Trike, and it shows in the ride quality and handling. The Trike Series Shocks valving and extra travel make a real world difference.





Important Note: Regarding the Twin Adjustable and Pro-Action Shocks: We ran both shocks on all the bikes/trikes, with multiple people test riding them. The ride quality is indistinguishable between the two. We did blind tests, and it was impossible to say that one rode better than the other.

Important Note: Regarding all the shocks we tested, but did not list in our charts:  Many were so poor in ride quality and/or handling, there was no reason to clutter the chart with them.  

There were a few shocks we tested that provided a small incremental improvement in ride quality, but the cost of those shocks are north of $1,000.00, many in the $1500-$2000 range.  We did not find small improvement (10-15 points) worth the 1.5 - 3.5 times the price difference.

*All prices listed in the chart are Retail.

See Part II of

Rear Shocks Testing Report HERE


Link to More Photo's & Details on Performance Shocks


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