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September 22, 2017

How to adjust suspension on a motorcycle

by biker1

How to adjust suspension on a motorcycle

This video is about adjusting progressive 422 motorcycle shocks on my 2006  American Ironhorse Texas Chopper. many of the same principles for adjusting these motorcycle shocks will apply to other models of motorcycles. But, it’s very important to first check with your motorcycle manufacturer as to the types of shocks recommended as well as the recommended adjustment to these motorcycle shocks.

A number of models of the American Ironhorse motorcycles used the same shocks, mounted horizontally under the frame. besides the Texas Chopper  I also know (because I owned one) these Progressive shocks were used on the Legend model (of the American Ironhorse model line) as well. Also, these same shocks were use on the Big Dog K-9. Again, I know this because I’ve owned  a couple of those Big Dog k9 models.

The advantage of having these horizontally mounted under the frame shocks  is that they help provide a lower rigid frame look to choppers, without having to put up with the harsh ride of a rigid frame. Plus,  in my mind, they provide a much cleaner look to any motorcycle. Who wants to look at too big bulky shocks mounted on the sides of your rear tire?

How to adjust suspension on a motorcycle

American Ironhorse Texas Chopper

2006 American Ironhorse Texas Chopper

 

Progressive 422 motorcycle shocks How to adjust suspension on a motorcycle

Progressive 422 motorcycle shocks

When you buy a new set of these Progressive motorcycle shocks they do come with instructions as well as a special tool that you see being used here,  to adjust the ride or as it’s called the preload of the shock absorber. Naturally all models of motorcycles  are somewhat different, so, it’s important that you first check your manual not only as to what  shock is utilized on your bike, but also what they recommend  as far as proper adjustment.

Big Dog motorcycle

Big Dog motorcycle

How to adjust suspension on a motorcycle

Adjusting the motorcycle shocks is also  geared toward the individual rider and how they want their bike to feel. if most of your riding done with a passenger, or just by yourself? Not only is this very important in adjusting your shocks,  but it might be something to consider  prior to actually purchasing a new set of shocks. As an example, Progressives motorcycle shocks sells two models of their 422 shock, one  model is their standard and the other one is a heavy-duty model. I would suggest before making a decision which model is right for you, it might be prudent to call the customer service department at your motorcycle parts distributor, and or the Progressive shock people themselves,  to determine the best shocks to install. Obviously, besides riding solo or with a passenger most of the time, I think a rider that weighs 150 pounds, and another rider on the same bike that weighs 250 pounds, are going to make different adjustments to their shocks in order to compensate for the weight difference.

adjusting Progressive 422 motorcycle shocks How to adjust suspension on a motorcycle

adjusting Progressive 422 motorcycle shocks

So, my best advice here, is do your research before actually purchasing a replacement set of shocks. Also, if you’re not handy with doing your own maintenance or mechanical work, I definitely recommend having new shocks installed and adjusted by a professional motorcycle mechanic.

From Wikipedia, the free encyclopedia:

The hydraulic shock absorbers used on the rear suspensions of motorcycles are essentially the same as those used in other vehicle applications.

Motorcycle shocks do differ slightly in that they nearly always use a coil-over spring. In other words, the spring for the rear suspension is a coil spring that is installed over, or around, the shock.

In terms of adjustment, rear shocks span the range from no adjustments whatsoever to pre-load adjustments only to racing shocks with adjustments for length, pre-load, and four different kinds of damping. Most shocks have internal oil reservoirs, but some have external ones, and some offer air-assisted damping.

A number of companies offer custom-built rear shocks for motorcycles. These shocks are assembled for a specific motorcycle and rider combination, taking into account the characteristics of the motorcycle, the weight of the rider, and the rider’s preferred riding style/aggressiveness.

Twin shock absorbers

Twin shock refers to motorcycles that have two shock absorbers. Generally, this term is used to denote a particular era of motorcycles, and is most frequently used when describing off-road motorcycles.

During the late 1970s and 1980s, motorcycle rear suspension design and performance underwent tremendous advances. The primary goal and result of these advances were increased rear wheel travel, as measured in how far the rear wheel could move up and down. Before this period of intense focus on rear suspension performance, most off-road motorcycles had rear wheel travel of about 3.5–4 inch (9–10 cm). At the end of this period, most of these motorcycles had rear wheel travel of approximately 12 inch (30 cm). At the beginning of this period, various rear suspension designs were used to reach this degree of performance. However, by the end of this period, a design consisting of using only one shock absorber (instead of two) was universally accepted and used. The performance of single shock absorber suspensions was vastly superior to twin shock motorcycles. Accordingly, this design distinction is readily used to categorize motorcycles. With the exception of Bentley and Draper system (New Imperial and Brough Superior machines) and the HRD (later Vincent) system both developed and patented in the 1920s it is only since the 1980s that monoshock motorcycles have been the norm, the term “twinshock” is now used to categorize vintage motorcycles. This distinction is important in that it provides classes used for vintage motorcycle competition. For example, vintage motocross races are held for older motocross motorcycles. To prevent the better-performing monoshock motorcycles from dominating the competition, there are separate competition classes for monoshock and twinshock motorcycles, which prevents them from competing directly against each other.

 

 

How to adjust suspension on a motorcycle

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