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This section is intended to help you assess your bikes condition and keep it in working order.
Remember this is a dh/freeride set up!
Contents
Rules to Live By
If you follow these simple maintenance tips on a regular basis your bike will last longer, perform when you need it to and keep its resale value.
- Never pressure wash directly into seals, bearings or pivots
- Never put your bike away wet
- Always keep it lubed up
- Keep your rotors and brake pads clean (use rubbing alcohol)
- Maintain proper air pressure in suspension and tires
- Check for any damage after crashes
- Stop riding as soon as you hear or feel anything wrong with your bike (In a lot of cases a different feel or sound is enough to signal a reason for concern)
Suspension
Ideally, suspension should keep wheels on ground level regardless of surface.
[Note: This is just basic information...and not license to destroy your suspension.
If you have any problems with your suspension, please take your bike in to Eric at Joe Mamma's and he will be glad to not only fix your problem, but explain what he did.]
Definitions:
Damping - the slowing or muting of kinetic energy
Sag - the amount your suspension compresses while you are in a natural riding position on you bike
Preload - the amount of force required to activate the suspension accomplished by precompressing a spring
Rebound - how fast the suspension comes back to it's full travel
Compression - compression damping determines how fast the suspension is allowed to compress
Set up your own "sag":
Sag is the amount your suspension compresses while you are in a natural riding position on you bike.
Always check the manufacturer's guide for sag suggestions.
Typically the front fork should have 15-30% sag and the rear shock should have 30-50% sag.
To adjust your suspension, get someone to hold the bike.
Sag should be adjusted in your natural riding position, typically this will be off the seat and centered over the bike.
Feel free to work the suspension a bit to get comfortable and centered but when measuring the amount of sag.
Do not bounce.
In most DH forks there are two major adjustments to be aware of, spring rate and damping.
Damping is often adjustable for both compression and rebound.
Spring rate
Determines how much force is required to compress the suspension a given distance.
Often expressed in lbs./inch, but also usually only written as lbs.
Example: a 600lb spring will need 600lbs of force to be compressed 1 inch.
If you have too much "preload", which is the pre-compression of your spring, you might be able to set sag correctly but your spring rate will still be too light given most suspension designs.
This can cause you to "blow through" your travel, using the suspension travel too quickly, resulting in bottoming out.
This not only puts extra strain on your suspension it puts extra strain on you.
Rebound
If the rebound is adjusted too slow, it will cause your suspension to "pack up".
This means that the travel will not have time to return to it's full length before a subsequent impact.
Again allowing for bottoming out which therefore causing serious damage to the suspension or the rider, i.e.. flying over handle bars!
| If your suspension does this... |
Do this... |
| feel like you're getting bucked off your saddle |
slow down the rebound |
| feel like your fork is punching you in the face |
slow down the rebound |
| - as soon as you hit something |
check spring rate, speed up compression |
| - as you're absorbing an impact |
check spring rate to ensure the fork isn't bottoming, try slowing compression as a quick fix |
| - after you absorb an impact |
slow the rebound damping |
| the front or the rear keep bottoming out for no apparent reason |
add dampening resistance or speed up the rebound |
| no dampening |
change oil |
| leaking oil |
check stanchions and shock shafts for scratches, replace seals |
Things that screw up your suspension
Air in the oil : caused by shaking oil prior to insertion in closed cartridge systems, low oil levels allowing air to easily mix with oil
Oil Level : incorrect oil levels can cause suspension problems
Water in the oil : caused by broken seals, riding in wet conditions
Scratches on your stanchions : this will cause your seals to tear so be careful!!!
While we're on the oil subject you should know that all mountain bike specific suspension is designed to use a 5-20 weight oil thickness.
Thin oil = quicker response
Thick oil = slower response
If your front fork does not have certain adjustments that you could use, determine whether or not changing the oil weight is an option for you.
!!! Almost all rear shocks are not user serviceable DON'T take them apart !!!
Tire Pressure
Tire pressure is definitely a personal thing.
Tires react differently depending on the conditions.
I personally like to run 30-35 psi.
Flat tires: When you are replacing a flat tire, assuming you are running tubes, look at the tube to determine where the flat occurred and what could have caused it.
| If this happens... |
Do this... |
| bouncing off everything |
remove some tire pressure |
| feel like the tires are slow and unresponsive |
add tire pressure |
| constant flats |
check rim tape |
| pinch flat (snake bite like holes found in the tube) |
add more tire pressure |
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