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Discussion Starter #1
I did it the easy way, removed the forks, unscrewed the top caps, turned legs upside down, let the oil out, then put new 500ml oil back in and forks back on the bike. I used a 10W and 15W blend that was lying around in the garage.
Didn't have the time to go for a ride yet, but I noticed that now its virtually impossible to bottom the forks on a static test (that is front brake applied and violently jerking the front end while on top of bike). In fact, a cable tie i put on the leg shows that only half the spring travel has been used (I repeat, this is not a ride test, just static). Never seen anything like that on this bike, so I guess I have done something wrong.

Is there any case I overfilled with oil? I did put 500ml per leg but maybe there was still old oil inside? Should I had the forks disassembled, in order to be able to let all of the oil out?
Should I had the caps screwed back when fork legs were compressed to prevent from keeping too much air inside?

Also, if i remove the caps and let the forks compress fully, what should the oil height be from the top rim? The manual suggests 73mm but with the spring and rod removed.
 

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Is there any case I overfilled with oil? I did put 500ml per leg but maybe there was still old oil inside? Should I had the forks disassembled, in order to be able to let all of the oil out?
Never fill forks by volume.
What is important is the air gap or the height from the oil to the top of the tube.
Always measure the original oil height before you drain the tubes so you can decide if you want to alter the air gap. You can do so without removing the spring since you aren't changing the fork volume. Changing springs will change the fork volume.
If one fork has less air gap than the other it will bottom earlier as well so it may only be one that's the problem.
Remove the caps, compress the leg and measure your oil height in each tube and WRITE IT DOWN so you can refer to it next time. Remove about 20mm from whichever is higher and remove whatever you need from the other to make it the same.

Did you blend the oil 50/50 before using it?
If you did then you have 12.5W which is fairly heavy oil (OEM is 8W) so you may find the front quite harsh.
 

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Discussion Starter #3
you always come to the rescue, much appreciated Bladeracer.
Unfortunately it is too late to measure original volume, but it seems that overfilling is my problem. It is strange though as I followed the manual figures.
I will drain some oil tomorrow and see.
I used more 15w than I used 10w, it should be about 13.5 as a rough estimate, but it does not seem harsh, provided I back off a bit on the damping adjusters, It just feels very oversprung as it compresses.
The caps should be screwed back on with the legs fully extended or partially compressed?
 

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I used more 15w than I used 10w, it should be about 13.5 as a rough estimate, but it does not seem harsh, provided I back off a bit on the damping adjusters, It just feels very oversprung as it compresses.
The caps should be screwed back on with the legs fully extended or partially compressed?
It will be more harsh with high-speed damping so you'll have to test ride it to see if you're happy with it.

I'm not sure what you mean as you have to extend the fork tube up to meet the cap to be able to screw it in. I can't imagine any possible way of putting the cap on with the fork partly compressed unless you put it in a press for some reason.
 

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my manual says to pump the fork to remove all the fluid before re-assembly?
You should stroke the fork several times while draining the old stuff out to empty the cartridge. It's not a bad idea to do it when refilling it also to ensure accurate air gap measurement.
 
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