1989 k model vfr forks spring & oil replacement

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spyrius
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1989 k model vfr forks spring & oil replacement

Post by spyrius » Thu Dec 29, 2011 9:52 pm

Hi all,
Is it possible to replace springs and/ or oil from front forks without need to remove forks from yokes? I have fork seals in good conditionand dont want them to be ruined when dismantling fork tubes. So, is it possible to unscrew top bolt and withdraw spring? I want to replace it with wemoto hagon progressive spring. I think my springs are weaken and worn, as i have bought bike a month ago and noticed when riding that i am bottoming out and frontfeel is quite rough over little bumps on road.

I have done previously seal removal on cbr250, so still remeber how it was frustrating to drive in seals without proper tool.

Enough of my rant... So is it or not?
Thanks in advance

phil x
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Re: 1989 k model vfr forks spring & oil replacement

Post by phil x » Thu Dec 29, 2011 10:08 pm

The forks have an oil drain stud on the bottom rear of each leg.
Remove the caps, compress forks & fill with oil to 90mm from the top (still compressed) unless Hagon suggest a different level, release the forks, install spring & replace the fork caps. Simples!

Phil

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lukemillar
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Re: 1989 k model vfr forks spring & oil replacement

Post by lukemillar » Thu Dec 29, 2011 10:28 pm

You should replace the oil when changing the springs. Reusing old oil is, like the suspension guy I used in Sydney once said, is like re-using a prophylactic!

You don't have to separate the stanchion from the fork bottom, so your seals needn't be affected, but I would remove the forks and up-end to drain the oil, rather than unscrew the damping rod bolt.

phil x
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Re: 1989 k model vfr forks spring & oil replacement

Post by phil x » Thu Dec 29, 2011 11:22 pm

lukemillar wrote:You should replace the oil when changing the springs. Reusing old oil is, like the suspension guy I used in Sydney once said, is like re-using a prophylactic!

You don't have to separate the stanchion from the fork bottom, so your seals needn't be affected, but I would remove the forks and up-end to drain the oil, rather than unscrew the damping rod bolt.
There is an actual drain bolt too ;)

Phil

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lukemillar
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Re: 1989 k model vfr forks spring & oil replacement

Post by lukemillar » Thu Dec 29, 2011 11:49 pm

Haha - So there is! Never noticed that before; I stand corrected

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CMSMJ1
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Re: 1989 k model vfr forks spring & oil replacement

Post by CMSMJ1 » Fri Dec 30, 2011 12:22 am

I'd still take them out the yokes and drain them properly. Pump all the old shit out and get them flushed through.

Leave the seals..that is no worries.

New springs is the best thing I did to my K model forks,
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Gixxerpilotdave
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Re: 1989 k model vfr forks spring & oil replacement

Post by Gixxerpilotdave » Sat Dec 31, 2011 5:46 pm

Im debating doing the springs in my forks, how did it go? is it worth it?

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skinnydog0_0
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Re: 1989 k model vfr forks spring & oil replacement

Post by skinnydog0_0 » Sun Jan 01, 2012 10:01 pm

CMSMJ1 wrote:I'd still take them out the yokes and drain them properly. Pump all the old shit out and get them flushed through.

Leave the seals..that is no worries.

New springs is the best thing I did to my K model forks,
:plus:
If you have the time, i would get them out and do it properly. You may as well do it right and not have to worry about getting the forks out again in a year or two's time. I would also change the springs ;) and the seals if they haven't been done in a while. If you do do the seals, you can use the old seal as a protector and a piece of scaffold tube split down the middle (or another piece of steel pipe from teh builders merchant) as the tool to drive the new seals into place.
An NC is for life, not just for Christmas!

spyrius
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Re: 1989 k model vfr forks spring & oil replacement

Post by spyrius » Tue Jan 10, 2012 2:59 pm

thanks for all reply's will let you know once done over weekend

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