How did I mess up rebuilding my forks?

[BlackAndBlue]

I rebuilt my forks mostly to put stiffer springs in. I installed 1kg racetech springs. I used all balls fork seals and dust seals. Everything was spotlessly clean before being assembled. I pressed the seals in with an appropriately sized fork seal installation tool. I filled the forks carefully to 130 mm of 15w fluid with the springs out and the legs compressed. After it was back together I went for one ride and by the time I got back the seals were leaking profusely. As though there was no seal at all. What could I have done wrong? The only things I could think of to cause this would be too much fluid or debris in the forks but I was careful to not allow those to be issues. What could have gone wrong? The one other possibility I thought of is that I didn't oil the fork tube before sliding the seal down and the seals were damaged?

 

[FinalImpact]

Fluid level is not likely a problem and I'd assume the stanchion tubes were scar free before repair and are in good shape now?

Lube / grease is very important and I pack both sides of the seal full and the inner lip so it doesn't chafe and damage the seal. That said this could be an issue if there was no lube at all.

More likely based on the quantity leaking is the retention spring was knocked off or what I don't recall is if the seal has a top and bottom? Does the old one look the same from both sides?

I know some have cut the seal during install right at the top of the tube.

Pop the dust seals and tape them up. Wipe all oil free. Depress nose a few times and look for a single line of oil OR is the seal coating/leaking 360° around the stanchion. If 360, the springs may be knocked off.

Sounds like you'll be going back in. Sorry.

 

[BlackAndBlue]

Oh i'very already started going back in. The one seal I got out already looked normal. It was oriented properly and the spring was in place. It appeared to be leaking 360 degrees around. I have to think it must have been the lack of lube. I oiled the seals up but the tubes were dry so it must have not been enough. I'll oil the whole tube up this time.

 

[BlackAndBlue]

Now I am having another problem in addition. Now that I have cleaned everything up, the upper fork bushing will not fit in to place. Last time it just dropped right in. Even taking it off the inner tube and holding it closed will not allow it to fit in to its groove. I don't understand that one at all.

 

[FinalImpact]

Did the bushing not drive in with force? If not maybe it got into the seal holding it open so to speak.

Off hand once the wiping edge of seal is damaged from a dry run, the seal may not recover...

Does the seal by it self wipe grease from the stanchion? Any chance it is the wrong one?

 

[BlackAndBlue]

Are you saying that this upper bushing is going to have to be driven in every time it is reinstalled? That may have been the problem the first time. The seal could have been damaged by driving the bushingles down. How does one drive that bushing down? I don't think my seal installation toll will do it.

 

[FinalImpact]

The bushing needs to be flush below the seal.... read the FSM. It should offer guidance. I don't have access at the moment.

When you pulled it apart, it pulled the top bushing out. This took force (should have). It will take force to drive it back in. What tool are you using?

 

[BlackAndBlue]

The bottom bushing will not fit through the top bushing so yes the top bushing has always come out. Maybe I just didn't notice that it didn't go back in. I will take a look at how to drive it back in.

 

[FinalImpact]

It does say to install the fork seal "number side up" but ya you need a proper driver to install the fork bushing. You can see in the outer body where it drives to depth below the seal. Make sure it is to depth.

 

[BlackAndBlue]

Okay i'Lloyd have the figure out how to drive it in then. I'might surprised that this step is not mentioned in any how-to article I read or video that I watched! Everyone just moves right on to driving the seal in.

Thanks for the info

 

[TownsendsFJR1300]

Did you get it back together?

 

[FinalImpact]

I found a vid of guy doing some USD forks on a CBR and be briefly started to drive the bushing in and then they conveniently edited that out skipping to seal install.

It starts off w guy in a gorilla suit taking the forks off.

Driver for $35
https://www.rockymountainatvmc.com/...43mm?v=13559&gclid=CJzYj4f6t9ICFQJrfgodSoIEvQ

 

[TownsendsFJR1300]

The correct size in schedule 40 PVC would do the job as well...

 

[FinalImpact]

^^^ Yes and true but that size doesn't exist. PVC can and does work but you need to cut 8 to 10 8in slices in it so it can be squeezed to 43mm. Zip ties, a hose clamp or even tap will hold it to shape.

Be sure to wear safety glasses and place a washer between the bushing and PVC as it will go over the bushings edge easily.

I made one last year and it works OK. It may still exist in an FZ6 thread on same topic?

 

[FinalImpact]

Pictures are gone after the server upgrade....
http://www.600riders.com/forum/fz6-...-steering-head-bearings-tires.html#post603811

This thread has a pic tho...
http://www.600riders.com/forum/how-...l-replacement.html?highlight=Fork+seal+driver

 

[BlackAndBlue]

I have not gotten it together yet. Inconveniently, the seal driver I bought for the seal has a recess around the inside edge that just perfectly fits around the bushing therefore it will not seat the bushing. I'll have to go find some pvc and get the bushing seated that way.

 

[BlackAndBlue]

Does the washer go in cone side up or cone side down?

 

[FinalImpact]

Does the washer go in cone side up or cone side down?

WHA???????
All washers should be flat.

With the bushing not seated and the seal locked in place, perhaps the bushing forced the washer into the seal bending it? Washer and seal should be replaced. Also make certain the outer tube is not burred up. It must be able to accept bushing without deforming it.

Sorry man. Tough day....

 

[BlackAndBlue]

I have new seals already. Old ones were not to be trusted.
The washer above my upper bushing was never flat. It's flat on one side and conical on the other. Raised on the inside. It's obvious to look at it that it was made like that, not deformed. That is not to say that it is the correct one, but I am fairly sure this is the first time these forks have been apart.

 

[TownsendsFJR1300]

Did you look at the parts fisch and see if that helps with what goes where?

I don't know your year bike, but here's the parts fisch for an 07:

Yamaha Motorcycle Parts 2007 FZ6 - FZS6W FRONT FORK Diagram