DBR suspension tuning guide.
Getting the suspension dialed in can be tricky. Use this guide as an aid to help you make the right adjustments.
DBR mechanical problems guide.
Tuning a suspension has little benefit when there is mechanical damage or neglect. This guide
can help you understand what kind of mechanical problems a suspension may have.
Article: How to revalve twin chamber forks.
How to revalve twin chamber sealed cartidge forks.
Using the 2010 KXF450 as an example, this presentation provides details on a complete revalve.
Here you will have sufficient information to learn what is involved with revalving forks.
How to service dirt bike forks.
How to replace fork seals, fork oil, fork springs and bushings.
SFF forks, PSF forks, open chamber forks, sealed cartridge forks, air forks and conventional forks.
How to change engine oil.
How to change engine and transmission oil on dirt bikes. How to replace a four stroke engine oil filter.
Article also gives general advice on good practices and explains the importance of oil change.
Engine troubleshooting guide.
Basic engine troubleshooting guide for two stroke carburated engines, four stroke carburated engines and four stroke EFI engines.
This guide is intended to help identify possible causes of various failure modes.
Dirt Bike Tires and Wheels Resources
How to mount the front wheel.
How to properly mount the front wheel so the forks are in alignment.
Careless wheel mounting can result in leaking forks.
Suspension on a dirt bike takes a pounding and it's only a matter of time until the fork seals leak.
If you are a serious dirt biker, you can count on fork seal related maintenance as part of your regimen.
No matter how likely fork seal replacement may be at some point, it is important to realize that there are many possible causes of leaking fork seals.
The constant motion of the forks can wear the seal lip enough that the lip of the seal can no longer seal against the fork tube.
A broken or stretched seal coil spring (the spring that is wrapped around the seal lip diameter) will result in a relaxed seal grip on the fork tube, facilitating leakage.
Seal material can be damaged as a result of harsh riding conditions, fork mechanical problems or improper assembly.
Seal material can fail by age (erosion the lip of the seal).
Contact with chemicals that the seal material is not compatible with, which may cause hardening, softening or deformation.
Seal installation problems
Seal retaining clip not fully seated in clip groove or is dislodged from the groove completely. This allows the seal to float around in the seal bore, which will likely result in leaking.
Seal not mounted squarely in fork tube. A seal will not seal properly unless it is fitted accurately. Because a seal is primarily made of
an elastic material, it is possible to have a secure fit while being crooked.
Missing back-up ring, if applicable.
In many designs, a steel back-up ring is mounted behind the oil seal.
If the back-up ring is missing, the seal can move in the seal bore, which will likely result in leaking.
Debris under the seal lip
A failed or worn dust seal will allow dirt to infiltrate the oil seal.
Dirt will eventually push into the oil seal lip,
causing a leak.
Fork alignment problems can open the sealing surface during fork movement, allowing material into the sealing area.
Fork alignment problems
Fork tubes not in alignment due to improper front wheel mounting. Improper wheel mounting can cause the fork tubes to be
out of parallel with each other.
Fork tubes not in alignment due to triple clamp problems. With a hard impact or crash, the fork tubes can be twisted in the triple clamps,
causing the forks to be out of parallel with each other.
Fork tubes not equal in mounting height.
Bent fork tube(s).
Inner fork tube surface severely worn, scratched, dented or pitted.
Inner fork tube out of round.
Fork slider bushings badly worn. Seals can open when there is sloppy fit between inner and outer fork tubes.
PARTS AND SUPPLIES
Need parts and supplies for your dirt bike? We have you covered with all the parts and accessories you need from aftermarket to OEM.