K9 fork oil change

[JeffM]

Gents i have been having issues with handling (the HD's are catching me, first i suspected a crack in the frame, then fork oil had gone off (it's a bit yucky), then steering head bearings.

What i found was the nut on my modified Duce trees had vibrated un-done, even with red locktite.

So i fixed that, and made a mental note to check monthly.

Deciding to give the forks a fresh drink, i went and purchased Screaming Eagle HD fork oil, i know a lot of you folks are using this stuff so i get 4 x 16oz bottles (because i got more than 10 oz out of each leg)
When i got home the manual defiantly states "ten ounces of 30 wt oil", but i have taken 450ml out of each instead of 300 ml.
Q. What do i do?

 

[woodbutcher]

have you changed the fluid and rebuilt the forks yourself before???? if you ride it as hard as you say, it seems like the fluid would be forced out around the seals with it overfilled that much. i would say to put it back to factory spec with 30 wt. fluid and new bushings and seals and keep your fingers crossed.

 

[JeffM]

Thanks Tom, i personally have not rebuilt the forks, however to get the bike complaint to AU spec we had to change the trees, fork tube length and a host of other stuff.
After compliance i changed it all back to spec except the 3 deg rake BDM trees.
So October 2011 was when all this happened, this would have been the last time the oil had been changed.
I had intended to run 50 wt as i have with my HD's i have had, but with the extra fork length i think this may jar a bit.
Do you think 300ml is as per the manual or 450ml as per the bike shop who did the tube change?

 

[TapioK]

You saying you have 0 degree triple tree now? And shorter tubes?
Rake and trail is actually rather important for good handling.... Could it be that shorter tubes made front too low and they "fixed" it by adding too much oil to keep front taller?

 

[JeffM]

Nah, still 12 inch overs, had to reduce rake so i could get the bike under the house, it raised the frame by 1/2" at the front, been that way for 5 years, did the trail and rake thingy back then, all good infact i have ridden a K9 with the 3 deg rake, and i would say mine handled better. Much better.
All my race bikes i always ran 50 wt to stiffen up the front end and i used that in the 12 HD's that i have had, always could ride around the outside of most people on a twisty road. But i digress.
So know one thinks they know why i have an extra 3 oz in my forks.
I may be as you say Tapio, oh and still no EFM auto clutch yet WTF. Must be coming via the moon.

 

[TapioK]

Mail is so slow sometimes... or it may be stuck in customs...


Sent from my iPad using Tapatalk

 

[Alexey]

The manual is written W30, oil 10 oz. You cut the tube that would make a little shorter fork. (Lesser degree). Fill oil on the manual.

 

[JeffM]

The manual is written W30, oil 10 oz. You cut the tube that would make a little shorter fork. (Lesser degree). Fill oil on the manual.

But it would not raise the frame to get it under my house.

 

[Alexey]

But it would not raise the frame to get it under my house.

You disassemble the front fork? Disassemble and look carefully. Decompresses the fork spring. The spring rests on the tube. The tube is cut a little. All. If you fill lot of the oil, there will be high pressure. Squeeze seals.
Imagine an amortization rack of the car. The cylinder oil, and a spring. Take away the the cylinder with oil. The car will continue to swing on the bumps. Oil is necessary for of oscillation damping.