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Discussion Starter · #1 ·
Well after 2 years and 24,000 miles, my fork seals have given up and started leaking :frown:. So do any of you good people out there know the type and quantity of fork oil needed when replacing the seals. I've had a good look and cannot find any info on it.

cheers

Antony
 

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~450ml each fork
Hard do definitively state oil weight, as different manufacturers have different measurements. I believe genuine Honda is somewhere between 7.5 & 10W, however a lot of us have found improvement in ride handling by going to 15W with some going as much as 20W, but again, can be more manufacturer difference in that though.
Personally I have Shell Rimula 15W
 

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Discussion Starter · #4 ·
Thanks for the answers, but I do have one more. Is the 130mm air gap with our without the springs in?
 

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Pulled the workshop manual out for this to get the definitive details, per section 16-25:

RECOMMENDED FORK FLUID: Pro Honda Suspension Fluid SS-8 (10W)

FORK FLUID CAPACITY (spring removed):
R = 503ml
F = 480ml
X = 453ml
all +/- 2.5mm

Slowly pump fork tube several times to remove any trapped air from the lower portion of the tube.
Compress the fork tube fully and measure the fluid level from the top end of the fork tube.
FLUID LEVEL:
R/F = 130mm
X = 160mm

Extend fork tube and install fork spring with tightly wound coil side facing down.
Install spring collar with the stepped side facing down.
Coat a new O-ring with fork fluid and install it into the groove in the fork gap.
Install the fork cap into the fork tube.

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Thinking I better go and check my fluid level myself as well; as I had done the suspension mods before getting the manual and just did a like-for-like with levels for what was in there when I disassembled mine.
 

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Discussion Starter · #6 ·
That's great, thanks.

I'm going to sort it out this weekend.

I've used a seal mate tool and that has stopped the fork seals leaking so all I need to do now is refill them with fork oil.
 

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I'm old and stuck in my ways, so I use non-Ford ATF (automatic transmission fluid) as fork oil. It has a viscosity of 7-7.5, additives to keep transmission seals supple, and used to be what the service manuals recommended.

A gallon is about $13 at Walmart. I also use the stuff as chain lube, and I change the fork fluid every two years, same as the brake fluid. Use the measurements listed (with the springs out) and the fork fully compressed. I mount the forks in a padded wood working vise and fill them in that before re-installing the forks, putting the wheel back on, adding the springs but not the caps, and pumping the forks some more to work the last of the air out of the forks.

The screws at the bottom of newer bikes are to hold the fork guts in place, they are _not_ for bleeding the forks.
 

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I was getting set up to do a tire change when i noticed my fork seals were bad. I just watched a video on changing the seals (Motorcycle MD's youtube video). He explains that you don't need to mess with the springs at all. Just separate the tube from the case after draining the oil from the bottom of the case by removing the bottom bolt. Any input on this would be appreciated. I'm also wondering how the forks are lined up vertically when reinstalling them after rebuilding.
 

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I was getting set up to do a tire change when i noticed my fork seals were bad. I just watched a video on changing the seals (Motorcycle MD's youtube video). He explains that you don't need to mess with the springs at all. Just separate the tube from the case after draining the oil from the bottom of the case by removing the bottom bolt. Any input on this would be appreciated. I'm also wondering how the forks are lined up vertically when reinstalling them after rebuilding.
Since part of filling the empty forks with new oil is to pump the fork upper and lower tubes to fill the lower reservoir, I can't imagine doing the job without removing the springs. which is the easy part of the job.

Delboy's Garage on Youtube has some very good videos. Here's the fork seal replacement one. includes how to make a homemade seal driver.
He also has a short video on aligning the forks.


Other videos suggest we replace the worn fork bushings while doing the seals. new bushings are cheap.
And I would replace the dust caps also since they keep grit away from the seals.
 

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here is a very nice video on how to do the fork service on the 500 range bikes:

I would add some tips to that, heat up the collar where the bushings seals are sitting when pulling it apart and putting it back together, I used the metal washer / spacer that sits on the bushing and a "softer" metal rod + hammer to seat the bushing correctly (do not scratch the stanchions though), also cut the old seal into 2 smaller pieces and use that to push the new seal in, you can then pull the smaller pieces out easier than if you would use the whole old seal
 

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Well after 2 years and 24,000 miles, my fork seals have given up and started leaking :frown:. So do any of you good people out there know the type and quantity of fork oil needed when replacing the seals. I've had a good look and cannot find any info on it.

cheers

Antony
Bel Ray used to be the standard. There are others though, probably just as good.

The weight of the oil is your preference. I used to like 15w - a mix between 10w & 20w when I couldn't find 15w.

Higher the weight, stiffer the ride!
 
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