Replacing fork seal on 2000 KX125?
- Thread starter gcann
- Start date
SoCal Steve
Member
- Jun 5, 2001
- 12
- 0
GCann;
Changing the fork seals on your bike is not all that difficult; but you do need some specialized tools in order to do the job right. There are also some proceedures you need to follow.
First tools:
An air impact gun to remove and install base valve into cartridge.
A 14mm Allen socket for above.
A seal driver to properly install seals and bushings.
A fork oil level tool to allow you to overfill and set oil height.
If you have access to the air tools, the additional tools will probably cost you about the same if not more than having a professional perform the service.
Here is an overview of the proceedure, with the forks off of the bike.
1. Remove fork cap from top of fork leg. Pour out all of the fluid. Use a thin open end wrench to reach the jam nut for the cap between the cap, bumper assy. and spring. Loosen and remove the cap from the cartridge rod; remove the spring.
2. Use the 14mm Allen to remove the base valve from the bottom of the fork leg. This will allow you to pull the cartridge out the top.
3. Pry the dust scraper out of the bottom of the fork upper tube. Remove the snap ring which retains the oil seal. Heat the outside of the upper fork tube around the seal/bushing area lightly to ease disassembly. Pull upward sharply on the fork upper to separate the two tube.
4. Remove the two fork bushings, washer, seals and clip. Clean all parts and prepare for reassembly.
5. Grease the lips of the oil seals and dust scrapers. Put a plastic sandwich type bag over the top of the fork tube and grease a bit to allow seals to slide on without tearing on the bushing grooves. Push on the dust scraper, snap ring, oil seal, steel washer, inner bushing and last the outer bushing which snaps onto the groove in the tube.
6. Slide the upper tube onto the lower. Use the seal driver to drive the oil seal and bushing into the tube. Use like a slide hammer; works best for me to hold the driver and seal stationary and slide the tube down sharply. Install the snap ring and press the dust scraper on.
7. Re-install the cartridge and base valve reverse of disassembly. Use some grease on the o-rings on the base valve assy. Set the clickers on the the comp and rebound all the way soft (counter clockwise) for bleeding.
8. Fill with fluid all the way to the top. Extend the tube and press your hand to seal the top. Press down quickly, keeping pressure inside the tube to force fluid into the cartridge. Refill almost to top. Bleed air by pulling and depressing the cartridge rod thru travel slowly. You will feel a smooth, consistant pull when fully bled.
9. Your KX forks have the bladder and need one addl step. There is a steel washer on the cartridge rod, which the spring holds against the cartridge when installed. You must remove the white spring guide and remove this washer. Put the guide back on and set the oil height spec in your service manual.
Now extend the cartridge rod completely. Remove the spring guide while holding rod up and drop the steel washer (restrictive barrier) back in. Reinstall the guide, put spring on and install the cap. Run the cap all the way down, then tighten the jam nut against it. Thread the cap into the upper tube, reset your clickers and your done!!
Sorry for the long winded explaination but that's what it takes.
SoCal Steve
Changing the fork seals on your bike is not all that difficult; but you do need some specialized tools in order to do the job right. There are also some proceedures you need to follow.
First tools:
An air impact gun to remove and install base valve into cartridge.
A 14mm Allen socket for above.
A seal driver to properly install seals and bushings.
A fork oil level tool to allow you to overfill and set oil height.
If you have access to the air tools, the additional tools will probably cost you about the same if not more than having a professional perform the service.
Here is an overview of the proceedure, with the forks off of the bike.
1. Remove fork cap from top of fork leg. Pour out all of the fluid. Use a thin open end wrench to reach the jam nut for the cap between the cap, bumper assy. and spring. Loosen and remove the cap from the cartridge rod; remove the spring.
2. Use the 14mm Allen to remove the base valve from the bottom of the fork leg. This will allow you to pull the cartridge out the top.
3. Pry the dust scraper out of the bottom of the fork upper tube. Remove the snap ring which retains the oil seal. Heat the outside of the upper fork tube around the seal/bushing area lightly to ease disassembly. Pull upward sharply on the fork upper to separate the two tube.
4. Remove the two fork bushings, washer, seals and clip. Clean all parts and prepare for reassembly.
5. Grease the lips of the oil seals and dust scrapers. Put a plastic sandwich type bag over the top of the fork tube and grease a bit to allow seals to slide on without tearing on the bushing grooves. Push on the dust scraper, snap ring, oil seal, steel washer, inner bushing and last the outer bushing which snaps onto the groove in the tube.
6. Slide the upper tube onto the lower. Use the seal driver to drive the oil seal and bushing into the tube. Use like a slide hammer; works best for me to hold the driver and seal stationary and slide the tube down sharply. Install the snap ring and press the dust scraper on.
7. Re-install the cartridge and base valve reverse of disassembly. Use some grease on the o-rings on the base valve assy. Set the clickers on the the comp and rebound all the way soft (counter clockwise) for bleeding.
8. Fill with fluid all the way to the top. Extend the tube and press your hand to seal the top. Press down quickly, keeping pressure inside the tube to force fluid into the cartridge. Refill almost to top. Bleed air by pulling and depressing the cartridge rod thru travel slowly. You will feel a smooth, consistant pull when fully bled.
9. Your KX forks have the bladder and need one addl step. There is a steel washer on the cartridge rod, which the spring holds against the cartridge when installed. You must remove the white spring guide and remove this washer. Put the guide back on and set the oil height spec in your service manual.
Now extend the cartridge rod completely. Remove the spring guide while holding rod up and drop the steel washer (restrictive barrier) back in. Reinstall the guide, put spring on and install the cap. Run the cap all the way down, then tighten the jam nut against it. Thread the cap into the upper tube, reset your clickers and your done!!
Sorry for the long winded explaination but that's what it takes.
SoCal Steve
SoCal Steve
Member
- Jun 5, 2001
- 12
- 0
GCann;
I applaud you for wanting to learn how to do it yourself. It is relatively simple, but I am speaking from experience. It may be a little intimidating at first, but take your time. It may help to do one leg at a time, so if you can't figure out reassemly you have a reference.
Removing the valving on the base assy. and disassembling the cartridge is a little more involved...... be carefull if you try.
SoCal Steve
I applaud you for wanting to learn how to do it yourself. It is relatively simple, but I am speaking from experience. It may be a little intimidating at first, but take your time. It may help to do one leg at a time, so if you can't figure out reassemly you have a reference.
Removing the valving on the base assy. and disassembling the cartridge is a little more involved...... be carefull if you try.
SoCal Steve
marcusgunby
LIFETIME SPONSOR
- Jan 9, 2000
- 6,450
- 2
No its not true.Have you tried the varius tricks discussed many times on the board-do a search for 'replacing seals'
