Posts made in May, 2010

What the hell is suspension sag and why would I want any?

Posted by on May 29, 2010 in News | Comments Off on What the hell is suspension sag and why would I want any?

measuring-sag-illustration1

OK, so now you know your shocks can be adjusted to fit your bike and weight, but where do you start? http://www.motorcyclepartsandaccessoriesblog.com/2010/03/10/jp-tech-tip-suspension-and-bike-fitment/ Naturally from the beginning and with an understanding that shocks work in both the up and down movements of the bike. If all pavement imperfections where bumps, shocks for the most part would focus on compression. Unfortunately, there are pot holes and other sorts of gaps that require a shock to function in the other direction, as well. To achieve this, a shock compresses a small amount under the weight of the bike and the rider, before it has even been asked to do any work.

bump-and-droop-travel-illustration

This is called Sag, and is adjusted via the handy Preload Adjusters we include on each PSI shock (as well as on most stock equipment). There are two key Sag measurements, the first is Free Sag, ideally measured from the center of the rear axle to an arbitrary point directly above the axle (a fender bracket, for instance). This is done off the stand and with a helper holding the bike straight up. A solid lift of the rear end (simply pick up the bike by the fender or rack as far as you can) will unladen the shocks and a Free Sag measurement can be taken. The next critical measurement is Rider Sag and this is done with the rider on the bike (hands on the bars and feet on the pegs) and a helper or two supporting it. A measurement is again taken from the center of the rear axle to the same point as before. The difference between the two measurements is your final Sag and for cruiser and touring bikes is generally expected to be .75” to 1.25” (depending on application). If your number is less, then the bike will require less preload, and if it is higher, more preload is needed. Twin shock bikes should always be adjusted with the equal preload on both sides. Turns out sag is not always a bad thing and a correctly set up bike will ride far nicer, deal with road imperfections better and reduce rider fatigue!

Read More

What shocks best fit my Dyna?

Posted by on May 3, 2010 in Bikes, Product | Comments Off on What shocks best fit my Dyna?

dyna-with-flame-shock2The Dyna is a one the the best all around riders in the HD lineup. Lighter than the baggers, handles better than the Softails and not afraid of eating up big miles. The one thing it lacks? Decent suspension, of course! Not a problem, we’ve always loved this model and have a complete line of shocks and fork springs to transform it into the machine it was meant to be!

http://www.progressivesuspension.com/drpatdyna.html

Read More