how do I add fork oil

[kx450f73]

can I add fork oil to a 07 kx450f without taking forks apart with kawi's dual chamber system?

I know some guys take caps off and add oil?

I want to clean the leaking seal (only one leaking) see if it works, take caps off compress suspension and add oil until even is that possible?

The seals and bushing just replaced 3 rides age for upteenth time, I don't want to do damage, but have a race before I can get them to a suspension tech to have them seriously checked out by an expert

[JA_Allen]

No, you can not do it this way. How these guys you say are doing it, is not right. Keep your bike away from them.

The forks are a dual chamber design. That cap is actually the cap for the inner damping cartridge.

Best way is to get the *service manual*, follow the steps:

1)take fr wheel off

2)loosen clamps

3)slide fork legs out

4)Use special tool (can buy this at any MX outlet, I have a TUSK one from rocky mtn) to loosen off the top cartridge cap from the outer tube.

5)Slide outer tube down a little

6)Discard old oil (it will be dirty, contaminated, if your doing this anyway, just get rid of it)

7) Use a ratio rite cup (I use those push cup measurers) and measure out the right amount in CC or OZs for your model bike/fork (conversion is your friend) of real fork oil.

8) carefully add the oil by the opening left from pushing the outer tube down

9) button back up the tube to the top cap

10) reinstall fork legs

11) tighten clamps to the RIGHT torque specs, you can really damage bushings and distort the outer tubes all the way down the length if you overtighten clamps

12) put wheel back on. I have already posted a detailed post about aligning the front wheel right so you dont pinch your seals. search my posts. and DO NOT use the brake for this as said by others in another post, you should use something in front of the wheel and push down before tightening the pinch bolts, not the front brake. I use a sidewalk curb or 2x4 to hold my front wheel for alignment when installing.

All takes me about 45 min.

[JA_Allen]

*Here is that post I did* wanted to save you the search

From the Service Manual, the procedure for centering and aligning the front wheel in the forks. Also prevents fork and seal binding:

"After installing the forks in the triple clamp, and after installing the front wheel, before tightening the right axle clamp bolts on the right fork

leg, pump the forks up and down 4 or 5 times to allow

the right fork leg to find a neutral position on the front axle.

NOTE

○Do not apply the front brake during this process to stop

the motorcycle from rolling forward. Put a block in

front of the wheel to stop it from moving.

• Tighten the right axle clamp bolts.

Torque - Right Axle Clamp Bolts: 20 N·m (2.0 kgf·m, 15 ft·lb)

NOTE

○Tighten the two clamp bolts alternately two times to en-

sure even tightening torque.

• Check the front brake for good braking power and no

brake drag. "

I have also witnessed seals leaking, even if only the triple clamps are loosened for fork height in the clamps, and alignment is note done afterwards. Whenever you loosen the clamps, always loosen the axle clamp first, then after fork height or triple clamp work, or fork work, go through the procedure above. If even a little side loading or binding, front and back, side to side, the seals will leak, and/or fork binding and harshness can occur, also bushing life in the forks could be reduced, if the procedure above is not performed.

[kx450f73]

willl defintely do this as well, they did begin to leak after a crash perhaps I knowcked it out of alignment

[drive01]

The easiest way to add a little bit (for example, you want to add 5 or 10 cc's cause your forks bottom easily) is to buy a food grade syringe from your local drug store. Try to get one with the mL or cc graduations marked on it. load it up w/ fork fluid, and inject it into your bleeder hole.

To clean the seal without pulling your forks apart:

use a card, from a deck of cards, wrap it around the lower fork leg, grab it with your fist, have a corner point up towards the upper tube (just make sure your not trying to shove a whole straight edge of the card into the seal). Stick it far enough in so it gets to the oil seal (if you want just pry down the dust seal and then do this) once its in far enough, slide the card all the way around the seal, to clear out any dirt that may be stuck.

But if your fork seal keeps leaking that often, most likely you got a nick in your fork sliders. very carefully check for any small nicks. If you do have one, put masking tape around the nick, so just expose the damaged section. use fine sandpaper, 1000-1200 grit, and carefully polish just the exposed damaged area.

Don't over do it, otherwise you'll rub off too much chrome (coating in our case). remove the masking tape and it should be smooth to the touch.

Good luck

[kx450f73]

thanks man apprecaite it

[numroe]

The easiest way to add a little bit (for example, you want to add 5 or 10 cc's cause your forks bottom easily) is to buy a food grade syringe from your local drug store. Try to get one with the mL or cc graduations marked on it. load it up w/ fork fluid, and inject it into your bleeder hole.

If we do that, then into what camber does the extra oil go? I'd guess the inner, but the oil amount to control the "air spring" effect at the bottom of the stroke, is the oil in the outer chamber - correct (y/n)?

After reading the service manual, I am assuming the oil per chambers does not mix after installation, or is this assumption completely wrong? Obviously I've not pulled apart any twin chamber forks and get a shop to do it. But I'm very curious to learn about this topic - in terms of bottom out control.

[drive01]

When adding oil through the bleeder, although it does seem like your adding to the inner chamber, you actually adding to the outer.

This is where you want to add the oil to increase bottoming resistance. Remember, you're adding through where you bleed excess air out. And so therefore you're displacing the air in that chamber with oil = correct chamber.

Yes, this controls the harshness at the bottom of the stroke. The air in your forks (outer chamber) is acts as an air "spring". The less air you have in there to compress, the harder it will be. Thats why adding the oil in place of the air makes it harder.

I hope this makes sense.

And you are right, the inner and out chambers do not mix.

[kx450f73]

I've only been adding a tiny tiny bit, to keep from damaging any internals, I have some fork skins coming, and am not replacing the seals until they get here. Should be here, like today! I hope. I have noticed though that it certainly stiffens up the shocks, as people have mentioned u really don't want to add much, drops at a time.