Tip for measuring fork oil height

Maintenance, repair, troubleshooting, etc.
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Jimbo
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Sat Jun 10, 2017 7:17 pm

Depends on how much you overfill. Slight amounts, like less than 1 oz may be hardly perceptable. If you add more than ithat, I would think it will start to get stiff rather quickly. Remember as you put in more fluid, you decrease the amount of air in the fork tube which acts as a spring too. Air is compressible, fluids are not.
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Hadaveha
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Sun Jun 11, 2017 5:51 pm

My chiton doesn't tell me a proper amount of fork oil is their a suggested amount of mil's.

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Hadaveha
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Sun Jun 11, 2017 5:52 pm

chilton I ment sorry

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Jimbo
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Mon Jun 12, 2017 6:21 am

Each fork leg holds 12.8 OZ. or 881 ml. I would suggest 15W fork oil to start as an improvement over stock 10W.

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Casper
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Mon Jun 12, 2017 7:50 am

The excess air pressure due to lower volume being compressed the same amount will blow the fork seals even sooner than normal.

That said, some people pressurize the air inside the forks using a schrader valve. As long as you haven't overfilled to where there isn't any expansion area, you might get away with it without issues.
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Hadaveha
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Mon Jun 12, 2017 10:09 am

Thankyou guys I used 20wt when I changed the fork oil. And I really think I have it overfilled. It's feels like bicycle forks. Lol.

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Casper
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Mon Jun 12, 2017 1:53 pm

Excessive damping/rebound caused by too thick of fluid, would make it feel like a non-suspended fork as well.

There isn't an issue about popping the forks open again and measuring the fluid height.
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sleekitwan
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Mon Jun 26, 2017 3:27 pm

As for too much oil damaging forks...think about the REST of the bike would be my priority!

Bulbs, wheels, etc all would be harmed by jarring shocks.

There is enough airspace to allow the 4.5inches of fork travel. Not much extra i suspect, but if u find u overfilled and have no device to extract, just drop a length of clean rag that will soak some up, or clean rope, or the scientific way a plastic tube that is long so you don't lose it, place it into fork then adter a second force finger over top of plastic tube.

Withdraw tube with finger still jammed on and the tube comes out full of oil, enough to make a difference in forks.

Repeat as necessary if u ain't removed enough.
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Jimbo
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Tue Jun 27, 2017 5:23 am

I would recommend that if you have not done any suspension upgrades to the rear shock, than you really should not use 20WT fork oil. 15WT is probably the thickest you would want with stock suspensions. Remember you want to keep both ends of the bike balanced front and rear. Too stiff at one end or the other messes up the handling and ride. I would suggest draining out the 20WT oil and go with a 10WT or 15WT oil...and don't overfill :) As I stated earlier in a post here, each fork leg holds 12.8oz each.

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Tue Jun 27, 2017 8:04 am

Jimbo wrote:
Tue Jun 27, 2017 5:23 am
I would recommend that if you have not done any suspension upgrades to the rear shock, than you really should not use 20WT fork oil. 15WT is probably the thickest you would want with stock suspensions. Remember you want to keep both ends of the bike balanced front and rear. Too stiff at one end or the other messes up the handling and ride. I would suggest draining out the 20WT oil and go with a 10WT or 15WT oil...and don't overfill :) As I stated earlier in a post here, each fork leg holds 12.8oz each.
This is good advice. Really good advice.

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