6 Tips To Help You Set Sag

Sag is the first thing any rider should do when setting up their bike, it’s the foundation to base everything else on.  So have you set yours? Or are you a little overwhelmed with all the articles and videos out there on the subject?  Setting sag can be a little intimidating, so here are 6 tips to help you get through the process!


Parks Tool Tape MeasureUse a metric tape measuring tape vs one in inches.  Using metric measurements is easier on your brain when adding and subtracting than inches.  Try subtracting 2-1/8″ from 3-5/16″. Not so easy is it? But take 135mm from 150mm and life is grand.  Using metric is much less confusing and makes it much, much, easier to read.  And because a millimeter is a smaller measurement than inches,  millimeters allow you to get a much more accurate measurement.


Have you tried coming up with ingenious ways to measure sag by yourself? Not the easiest thing to do, so do yourself a favor and ask some friends to help.  If you have a stable wheel chock you can get away with one person, if not you need two people.  One to hold the bike up and one to take measurements.  And make sure you designate one person to take measurements.  This helps keep down confusion and maintain accuracy.


Take notes! Notes are key to helping you tune and troubleshoot.  Did you set the preload at 5 or 6 turns in? What springs do you have in the forks? What’s the sag in the back? If you take notes, you have one less thing to worry about.  And if you don’t want to use a pen and paper check out iMoto Suspension.
Take suspension notes.


You measured, adjusted and measured again.  But your numbers don’t make any sense! Has this happened to you? The numbers you’re getting are counterproductive to the adjustments you’ve made.  This is due to stiction! Here are a couple key points.

– Don’t bounce on the bike to get it settled.  You’ll NEVER get the same number twice.  Instead have the person measuring slowly push down on the bike and use their weight to allow the suspension to slowly return back to it’s resting point.

– Use the same reference points on the bike to take measurements, don’t pick a new one every time.  And if you don’t have one, make one.  A piece of blue painters tape on a fairing makes a great marker.

– When measuring rear sag, try and measure to a point directly above the axle.  This will give you the most accurate reading.


Setting Suspension SagDo you know what sag numbers you should use? Scouring the internet, books, and videos have you seen a range of sag numbers to use? So whats the right answer? Well there really isn’t a clear cut number to go by.  Your overall goal is to get the suspension into the top third of the stroke.  This helps keep the suspension from bottoming and topping out, all while allowing the suspension to operate properly.  So pick a reference and go with it.  Worst case scenario it doesn’t suit your riding and you adjust it!


So you called your buddies, got on your bike, and set your sag.  CONGRATULATIONS! You’re well on your way to getting a well handling bike.  But let me ask you a question.  Do you know how to tell if you’re on the right track for sag?  Can you tell if you need new springs?

Here is a good indicator, free sag.  Free sag is the distance between the bike with the wheel off the ground and the bike sitting under it’s own weight.  If there is no or very little free sag than you probably have too much preload and need to go to a stiffer spring.  If you have too much free sag than you don’t have enough preload and probably need to go to a softer spring.  It’s that easy!

Setting Sag…

Let’s be honest, they don’t call suspension “the black art”  for nothing.  There are a lot of moving parts to suspension.  But breaking them down into smaller parts helps us understand and figure out how to get a well handling bike.  So what are you waiting for? Grab your buddies, a pad and paper, and go to town.  You’ll thank yourself after that first ride.

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