By Seb Kemp
Some suspension units come with handy markings for sag. Others require the user to use a tape measure. It's always worth spending the few minutes to do this. And check them again and again, regularly. Things change.
This weekend, before setting out on your ride, spend five minutes going over your bike, checking the dials, presets, and science tubes that adorn your all- terrain vehicle. It might save your cherished and long awaited ride.
Don't just set and forget. Keep tabs on your tire pressure as it may change over time, in different conditions, and even weather.
Tires
When was the last time you checked your tire pressure? When you first bought the bike? When you repaired a puncture on the side of the trail? When you took the bike out of its winter hibernation? Well, it’s overdue for a squeeze.
Tire pressure will really affect how the bike handles so it’s worthwhile keeping pressure in its optimum range. Tires lose pressure all the time (tubes aren’t perfectly air tight, tubeless systems do leak slowly) so check them regularly otherwise your bike will be slowly changing each ride.
Also, think about the optimum tire pressure. The obvious thinking is that high pressures means faster rolling. Sure, this is true for tires rolling on smooth surfaces but mountain bikes generally negotiate rougher terrain and it has been found that lower pressure will allow tires to roll faster. Yes, faster!
Peter Nilges did his graduate dissertation at the German College of Physical Education, Cologne, and researched the subject of rolling resistance. Most rolling resistance tests are done on tarmac with skinny wheels, so how does this compare to the varied terrain that mountain bikes cross. The answer is that it does not compare at all. Hard and skinny is the rule for low rolling resistance on tarmac with road bikes, but mountain bikes have their own rules. To read the full report go HERE.
Basically, he found that fatter, lower pressure tires rolled better across off-road terrain; the reasoning being a tire with less inflation can adapt to unevenness more easily.
So, have a squeeze of your tires or get out a gauge. Make sure you know where you base setting for tire pressure is and play with pressure a little bit. It might make a radical difference to your bike. More than going out a buying a brand new gizmo. It might actually make a bigger difference to the rollover and traction of your bike than ‘upgrading’ to 650b.
The ring on one of the fork stanchions is a handy indicator of sag and travel used. Keep an eye on it.
Front Suspension
If your front tire is tracking well then the rear will follow. There are a few incidents where this might be overstating the importance of the front wheel, but generally it’s true; Your front wheel does most of the work and you should be able to control your bike from the front wheel.
One essential thing that many riders don’t realize is that the more weight they apply to the front wheel, the more traction they will gain. Of course, if your suspension forks (you are running suspension forks, aren’t you?) are not properly setup or tuned, then you’re going to sacrifice some traction.
Setting those forks up properly doesn’t take long. Get a shock pump and check the sag first. Are they running at the manufacturers recommended sag (generally 25-30 percent of the fork’s ultimate travel)? Make sure they are. Now, all those confusing red and blue dials:
Red refers to rebound damping and it controls the speed at which the fork returns after compressing. More rebound damping equals slower rate of return.
You want to have your fork set so that it springs back quickly enough that it doesn’t pack down on repeated hits, but no so fast that it bucks you off. A simple test is to start off with the damping adjuster set in the middle of the range. Next, forcefully compress the suspension and then lift the bike sharply. The wheel should leave the ground slightly. If it lifts right off the ground then there’s too much damping (slow), if it pushes back against you then it is too fast. Add one click at a time to either to slow or speed up shock.
Blue refers to compression – the speed and control under compression forks and is usually achieved through resistance (oil forced through ports of shim stacks), with more resistance creating a slower compression rate.
Low-speed compression controls the force on the suspension under low speed movement – pedaling, braking, body movement. You want to adjust it so its “firm” enough that the fork isn’t a bobbing mess on climbs and so it doesn’t dive under breaking, but, again, not so firm that you sacrifice front wheel traction and control.
Compression damping can be hard to get right. The best technique is to start with the dial right in the middle of its adjustment range. Go riding, and if the bike feels harsh and inactive then remove a click at a time until it feels compliant. If the bike is blowing through its travel easily, add a click at a time until it’s stable, yet still plush. It’s a case of trial and error and does require some patience. Remember that sag must be correctly set first. One can not mask the affects of the other.
Some suspension units come with handy markings for sag. Others require the user to use a tape measure. It's always worth spending the few minutes to do this. And check them again and again, regularly. Things change.
Rear Suspension
There are a lot of similarities between setting up the front and rear suspension. One common mistake, however, is assuming that if the bike feels comfortable and mushy in the parking lot, it will be just as kick-ass out on the trail. No, no it won’t. It will probably bottom out constantly, leading you to damage your pricey suspension units, and to underperform out on the dirt.
Properly-adjusted rear suspension will give you:
- Limited suspension feedback in heavy compressions, deep berms, or steep lips.
- Limited deflection from roots, and/or rocks, dips, soft surfaces, off-camber terrain.?
- Ability to hold a sideline longer, without being sucked down to the center-groove of the trail: increases line selection capabilities, opens up a rider’s options to round-out or square-off corners, gives the rider increased confidence to look ahead.
It's very rare that a ride will be hosted by the excellent Western Spirit staff. You might need to be a little more self-sufficient. Make sure your pack contains more than a good sandwich. What about a spare tube (without holes), a gear cable, tire levers, allen keys, knife, patch kit, tire boot, first aid kit, emergency blanket, jacket or second layer, and clean water?
Pack
When was the last time you checked your pack? Are you sure that emergency Cliff bar is still in there? Do you have a fresh tube stowed safely? Is your first- aid kit up to spec? When was the last time you cleaned that bladder?
It’s easy to get complacent with your own pack; thinking that is must be fine because you barely ever delve into it. However, when you need those spares, repairs or emergency wares you really need them. So examine the contents of your pack before heading out this weekend. Make a list of what you should have in there and check it all off. It takes a few minutes and could save you a long, miserable walk out of the woods.
Improperly tuned brakes can really slow you down. It takes moments to check them and can save you from disaster.
Brakes
Two things to consider with your brakes: are they working correctly and are they setup right?
Check the pads to make sure there is plenty of meat left on them. Do they rub? Is it a warped disc or are the pistons not retracting? Both will slow you down and turn your jaunt into a marathon. Are the hydraulic lines free of tears or holes? They should be and if not then take your bike to a mechanic ASAP.
Set-up of your brake lever is personal, but here is a general guideline:
Place your hands on the bar with your outside of your hand at the extreme of your bar, extend your index fingers. The last 1cm of your brake levers should be set to fit comfortably where your index fingers naturally extend. Your modern hydraulic brakes only require one finger and the rest of your fingers should be utilized to hold onto the bars. Move them in- or out-board as necessary, adjust the reach so they fit, and have them hang at approximately 45-degrees.
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