05 450X need fork knowledge!

[RoHo]

I have never worked on these forks and I need info.

Are these the twinchamber forks?

What special tools do I need to change seals/bushings?

How much, and what wt/kind of oil?

Any tips would be greatly appreciated.

He bought this bike about 3 years ago. It looked like new and he has only ridden it about dozen times. I doubt that the forks have ever been apart.

I have been riding and wrenching dirt bikes for nearly 40 years. The last 10 on KTMs. I am doing this for a good friend of mine who is a very very busy auto mechanic. In typical mechanic fashion he rarely works on his own stuff, so I volunteered to do it for him. He has worked on my vehicles many many many times late at night and weekends.

Thanks for any help you can offer.

Edited May 28, 2013 by RoHo

[FORMA MOTO]

Go to the 450R forum.

At the top of the forum is a great article on how to re- build Showa forks, including mid valves, bottom valves and shim stack tuning.

[Jim Dettman]

I think your looking for something more like this:

Fork seals, change on motorcycle part 1 (of 2), twin chamber

Jim.

[5kcstq]

I completely rebuilt the forks on my 05 a few months ago... not very difficult, but certainly a bit fiddly.

The forks are Showa twin chamber design with a damper rod. The trickiest part of the job for me was bleeding the inner chambers and rods appropriately. It takes time and patience and the right method. I used Honda performance 5wt fork oil. You'll need at minimum a fork seal driver of some sort... you can buy one or make one out of pvc. Otherwise, the forks can be rebuilt using common tools.

Take your time and be thorough with the inner chamber bleed. The first leg took me about 4 hours, the second leg took me about 1 hour.

Hope that helps.

[RoHo]

I think your looking for something more like this:

Fork seals, change on motorcycle part 1 (of 2), twin chamber

Jim.

I watched this video. It doesn't tell you how much oil to put in either place.

[RoHo]

Take your time and be thorough with the inner chamber bleed.

Hope that helps.

Can you elaborate?

I have changed fork seals dozens of times, but never on a twin chamber. It looks fairlty simple, but looks can be decieving.

Go to the 450R forum.

At the top of the forum is a great article on how to re- build Showa forks, including mid valves, bottom valves and shim stack tuning.

Thanks...............for ALL replys!

[5kcstq]

Can you elaborate?

I have changed fork seals dozens of times, but never on a twin chamber. It looks fairlty simple, but looks can be decieving.

Thanks...............for ALL replys!

To change the oil in the inner chamber, you'll need to completely dump out all the old fluid by pumping the damper rod a few times to expel the old oil.

To refill:

1. Collapse the damper rod fully

2. Fill the inner chamber with 190cc of 5wt Honda HP fork oil.

3. Slowly pull the damper rod to full extension to draw the new fluid into the chamber. You'll need to pump the rod a number of times slowly to completely bleed all the air out of the chamber. This process takes patience and time. You'll be able to feel when the damper is bled fully, as the resistance will be equal throughout the full stroke.

4. With the damper rod fully extended, SLOWLY screw the inner chamber cap back on. There will be a fair amount of resistance as you push the cap down in the chamber and begin to thread it as it needs to expel all excess oil out from around the top seal and out of the inner chamber. Don't force it... with patience it will push the excess oil out and fully tighten. Torque spec for the cap is 22 ft.lbs

5. Verify the damper is bled correctly by compressing the damper by hand fully and letting it return. If all went well, the damper rod will fully extend on it's own. If it does not, you must repeat the entire bleed procedure. Don't be tempted to put the damper assembly back if the damper isn't bled correctly as you're fork leg will be virtually worthless.

Keep in mind, it isn't necessary to do the inner chamber if all you're wanting to do is seals and outer oil change. The inner chamber is sealed so with just a seal and wiper change, it won't bleed out on it's own unless you open the inner.

Hope that helps.

[Jim Dettman]

Apparently you didn't watch part 2:

Jim.

[RoHo]

To change the oil in the inner chamber, you'll need to completely dump out all the old fluid by pumping the damper rod a few times to expel the old oil.

To refill:

1. Collapse the damper rod fully

2. Fill the inner chamber with 190cc of 5wt Honda HP fork oil.

3. Slowly pull the damper rod to full extension to draw the new fluid into the chamber. You'll need to pump the rod a number of times slowly to completely bleed all the air out of the chamber. This process takes patience and time. You'll be able to feel when the damper is bled fully, as the resistance will be equal throughout the full stroke.

4. With the damper rod fully extended, SLOWLY screw the inner chamber cap back on. There will be a fair amount of resistance as you push the cap down in the chamber and begin to thread it as it needs to expel all excess oil out from around the top seal and out of the inner chamber. Don't force it... with patience it will push the excess oil out and fully tighten. Torque spec for the cap is 22 ft.lbs

5. Verify the damper is bled correctly by compressing the damper by hand fully and letting it return. If all went well, the damper rod will fully extend on it's own. If it does not, you must repeat the entire bleed procedure. Don't be tempted to put the damper assembly back if the damper isn't bled correctly as you're fork leg will be virtually worthless.

Keep in mind, it isn't necessary to do the inner chamber if all you're wanting to do is seals and outer oil change. The inner chamber is sealed so with just a seal and wiper change, it won't bleed out on it's own unless you open the inner.

Hope that helps.

Thanks, that is what i was looking for!!