Fork oil old okay?

TMUS

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I'm doing new springs, seals and steering bearings. I have a sealed bottle of bel-ray 10w that is about two or three years old I want to get a bottle of 5w and mix together. Any reason the sealed 10w would be an issue?
 
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That sounds like new oil to me..........I have used fork oil from a clean container that is probably 10 years old with no known problems. I have a couple of new, never opened Belray fork oil for my Super Tenere that I am sure is 2 years old. I will change it the next time the front tire is changed and all will be good.
 
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I doing new springs, seals and steering bearings. I have a sealed bottle of bel-ray 10w that is about two or three years old I want to get a bottle of 5w and mix together. Any reason the sealed 10w would be an issue?
Yes, you will be fine using that. I would use it even if it had been opened as long as it had been tightly sealed. Bel-Ray makes good stuff. Suspension fluid is not like brake fluid, it is not hydroscopic. It breaks down from use and contaminants.
I change mine about every 15k miles, most recently this past Sunday, and it was filthy.
Curious as to why are you mixing 5w and 10w? Shooting for 7.5w? OEM is 10w and I keep it that way even though I am pretty small at 180 lbs., it just works , at least for me.
 
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I doing new springs, seals and steering bearings. I have a sealed bottle of bel-ray 10w that is about two or three years old I want to get a bottle of 5w and mix together. Any reason the sealed 10w would be an issue?
Since fork oil is not hygroscopic (does not attract water) the Bel-Ray should be fine. You probably already know this, that by mixing 10w with 5w (I'm assuming a 50-50 mix) you'll end up with a 7.5w oil. Do you really want to go to a lighter weight? Just asking.
 

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7.5 is a recommendation that I followed and am happy with for touring more than sport riding after upgrading to stiffer springs.
 
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TMUS

TMUS

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I am thinking now maybe all the of 10wt and half quart of the 5wt, maybe a 8-81/2wt. Should be enough to do both forks.
 
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I change mine about every 15k miles, most recently this past Sunday, and it was filthy.
OEM is 10w and I keep it that way even though I am pretty small at 180 lbs.
Wow, that's often. Do you take off the forks or can you change the oil without removing them.

Also, my last Honda bike called for ATF fluid and I never had to remove the forks. I think Automatic Transmission Fluid falls in the range of 10W. I'm in the same weight category as you.
 

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I am thinking now maybe all the of 10wt and half quart of the 5wt, maybe a 8-81/2wt. Should be enough to do both forks.
You will need to use about 45oz of fluid to do both forks. So if your bottle size is a quart you will need two. If your bottle size is a pint like Honda's, you will need three...
 

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SAE weight can be a poor method of choosing fork oil because very thin oils like suspension fluids do not measure well under the SAE method. One brand of 10 wt may act thinner in motorcycle suspension use than another brands 7.5 or even 5 wt. My routine is to clean out the fork internals every 15 to 20,000 miles and replace the fluid with a 2:1 ratio of Honda's SS7 and SS8 fork oils which is a 6.7 weight mix. Honda SS8 is the OEM fluid. These links show a chart or list of some popular fluids ranked by operating characteristics.

http://www.qemsc.com.au/documents/suspensionoils.pdf

http://mahonkin.com/~milktree/motorcycle/fork-oil.html
 
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TMUS

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You will need to use about 45oz of fluid to do both forks. So if your bottle size is a quart you will need two. If your bottle size is a pint like Honda's, you will need three...
Thanks Scooter, I was hoping someone would know how much I will need.
 
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I could see changing fork oil maybe once a year on forks with adjustable damping, and I know most don't. But on plain damping rod forks I would think it's nowhere near that necessity. Then again, are there really any good (realistic) guidelines by any of the manufacturers?
 
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SAE weight can be a poor method of choosing fork oil because very thin oils like suspension fluids do not measure well under the SAE method. One brand of 10 wt may act thinner in motorcycle suspension use than another brands 7.5 or even 5 wt. My routine is to clean out the fork internals every 15 to 20,000 miles and replace the fluid with a 2:1 ratio of Honda's SS7 and SS8 fork oils which is a 6.7 weight mix. Honda SS8 is the OEM fluid. These links show a chart or list of some popular fluids ranked by operating characteristics.

http://www.qemsc.com.au/documents/suspensionoils.pdf

http://mahonkin.com/~milktree/motorcycle/fork-oil.html
Honda SS-8 is 10W, and is OEM in a ST1300. I have substituted BelRay 10W and cannot tell the difference other than color, and price. BelRay is cheaper.
 
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The forks must be removed to properly change the fork oil. It is a very easy job if you coordinate it with a front tire change and follow the directions in the service manual. I drain and flush out thoroughly with WD-40 till clear then flush that out with ATF, drain that out and fill with SS-8 (10w) or Bel-Ray 10w. I do this every 15k miles on my touring bikes, and every 10k miles on my sport bikes. You will not believe how filthly the oil gets between 15k mile changes. If you think about it, it really does live in a harsh environment.
 

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Honda SS-8 is 10W, and is OEM in a ST1300. I have substituted BelRay 10W and cannot tell the difference other than color, and price. BelRay is cheaper.
When I set the sag up in my ST1300 forks I first used Bel Ray 10w and did not like it. I tried a 1:1 mix of SS8 and SS7 to 7.5 then settled on the 2:1 mix of 6.7. I've been happy with that for over 100,000 miles.
 
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TMUS

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Update

Picked up a new Bel-Ray 10wt. Going to use one in each fork, or do you think I should mix the old and new 10wts together ?
 
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Have never changed the fork oil in my2003 ST1300. Is it necessary to remove the forks to do this? Just curious, as I may need to add this to my to-do list.
 
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TMUS

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Have never changed the fork oil in my2003 ST1300. Is it necessary to remove the forks to do this? Just curious, as I may need to add this to my to-do list.
Yes, no way to drain or get the caps off, not that bad to do while doing a font tire change.
 
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Done, all back together, all went good except bottom race gave me trouble, a heat gun through the upper race for an hour on low, race in freezer finally went in. Now for a test drive when the rain stops.
 
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Yes, you must remove the forks to do this.
Change frequency is much more dependent on mileage and riding conditions than age of the oil.
 
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The forks must be removed to properly change the fork oil. It is a very easy job if you coordinate it with a front tire change and follow the directions in the service manual. I drain and flush out thoroughly with WD-40 till clear then flush that out with ATF, drain that out and fill with SS-8 (10w) or Bel-Ray 10w. I do this every 15k miles on my touring bikes, and every 10k miles on my sport bikes. You will not believe how filthly the oil gets between 15k mile changes. If you think about it, it really does live in a harsh environment.
Quick clarification...Do I need to remove the damper to change oil in the forks...The method mentioned above is how i have done mine for the past 5 years on my old VTX with the exception of using brake clean.

I am assuming that i do not need to remove it and all i need to do is flush them with the damper and valve in them as i have done in the past?

Thank you all.
 
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