Checking fork oil level
Banned
Joined: Oct 2007
Posts: 11,436
Likes: 13
First iv'e ever heard of it, CHECKING FORK OIL.
Only WAY TO NO FOR SURE IS TO DRAIN AND REFILL!!! ONLY then will you know EXACT AMOUNT IN THERE. Do my FORKS every SECOND year along with TRANNY!
Only WAY TO NO FOR SURE IS TO DRAIN AND REFILL!!! ONLY then will you know EXACT AMOUNT IN THERE. Do my FORKS every SECOND year along with TRANNY!
Last edited by hpfatboy; Sep 29, 2009 at 04:09 AM.
Novice
Joined: Jul 2009
Posts: 24
Likes: 1
From: Pipersville
re: fork oil
The older bikes required the removal of the forks themselves,turning them upside down, draining, pumping the forks to get everything out and then refilling...all through the top cap.
The newer models have drain plugs which makes it a easier job. Remove drain plugs, pump forks to expel all the old fluid , replace drain plug and refill at the top cap....about 9 or ten oz. depends on the model.
Doing this every couple years saves your fork seals and makes everything work like it should.
I wouldn't bother trying to check the levels...but I guess you could remove both top caps and measure the distance down to the fork oil....trouble is not sure what the normal distance should be.
The newer models have drain plugs which makes it a easier job. Remove drain plugs, pump forks to expel all the old fluid , replace drain plug and refill at the top cap....about 9 or ten oz. depends on the model.
Doing this every couple years saves your fork seals and makes everything work like it should.
I wouldn't bother trying to check the levels...but I guess you could remove both top caps and measure the distance down to the fork oil....trouble is not sure what the normal distance should be.
Tourer
Joined: May 2008
Posts: 442
Likes: 0
From: High Desert of So Cal
Unless your seals are leaking, you have no reason to check the fork oil level. But if it's still a concern, do like pogden says. You'll want plenty of shop towels cuz it can get kinda messy.
Tourer
Joined: Jun 2008
Posts: 283
Likes: 0
From: Delaware
I check or change my fork oil if or when I ever have to replace the seals. Dont really see the point of changing it. Just a way for the dealer to get money.
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Novice
Joined: Jun 2009
Posts: 19
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From: Illinois
Since you need to remove the springs, bottom the fork, and stand it vertically, I find it easier to just remove them. But yes, I have done it on the bike...once. Refering to adjusting the level, not changing the oil.
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Tourer
Joined: May 2007
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From:
I'm with those that suggest not checking, but instead replacing. I did mine yesterday. Was surprised at how contaminated the oil appeared. Fork oil takes quite a beating, and is likely subject to air entrainment and/or emulsification. Just for fun, might send a sample in of UOA just to see what's happening. Either way, it's easy to replace, and seems worth the effort, but maybe that's just me.
Novice
Joined: Jun 2009
Posts: 19
Likes: 0
From: Illinois
I'm with those that suggest not checking, but instead replacing. I did mine yesterday. Was surprised at how contaminated the oil appeared. Fork oil takes quite a beating, and is likely subject to air entrainment and/or emulsification. Just for fun, might send a sample in of UOA just to see what's happening. Either way, it's easy to replace, and seems worth the effort, but maybe that's just me.
I have know idea why the OP wants to check the level. Forks don't consume oil like a motor so it's not a maintenance issue. But, I do know that it is a tuning method, standard procedure, and H-D makes a tool for it; part# HD-590000-B.
Say I just changed the oil and now I want to change the rate and progression of the air spring by adding 10mm of oil level. Changing the oil again is not necassary... just measure the level and add (or subtract) oil.