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  • Asmith
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    by Asmith » Sat Apr 18, 2009 9:28 pm

    If you turn the rebound so that fluid could come out the bleed holes, did fluid continue to come out?

    The rebound rod should extend fully, if it doesn't, it's not right.
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    kerrycorcoran
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    by kerrycorcoran » Sat Apr 18, 2009 9:38 pm

    ~ wrote:If you turn the rebound so that fluid could come out the bleed holes, did fluid continue to come out?


    Not sure what you're asking?
    07 CRF450r
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    kerrycorcoran
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    by kerrycorcoran » Sat Apr 18, 2009 9:40 pm

    ~ wrote:The rebound rod should extend fully, if it doesn't, it's not right.


    I am positive, on both forks, it wouldn't extend to the fullest. What is the impact?

    Perhaps I wasn't patient enough allowing full extension. Or does it immediately extend or is it a delayed extention?
    07 CRF450r
  • PaiNLeSS
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    by PaiNLeSS » Sun Apr 19, 2009 5:03 am

    kerrycorcoran wrote:
    ~ wrote:The rebound rod should extend fully, if it doesn't, it's not right.


    I am positive, on both forks, it wouldn't extend to the fullest. What is the impact?

    Perhaps I wasn't patient enough allowing full extension. Or does it immediately extend or is it a delayed extension?


    The damping rod should extend at a smooth and steady pace until it hits the stops.

    If it doesn't extend fully, it's because it ran out of oil and hit air, which means you're looking at a re-do.

    What's the " impact " of the rod not fully extending? Several things, none of them good.
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    kerrycorcoran
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    by kerrycorcoran » Sun Apr 19, 2009 10:22 am

    Can someone take a look at this video:

    http://www.another site.com/tv.php?id=YjGjSsWyMqA(about 1:50 minute into the video)

    And let me know if this process will not work. This is what I followed to fill the Dampening Assy.

    Not looking for generalization of "bad", looking for specifics as to why it will not work and how it should properly be done.

    Anyone?
    07 CRF450r
  • Asmith
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    by Asmith » Sun Apr 19, 2009 11:07 am

    The video is pretty good.

    Where my process differs is the amount of oil he puts in and then wastes. It does not need to be at the level of the bleed holes, 50mm above the bottom is more than enough.
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    kerrycorcoran
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    by kerrycorcoran » Sun Apr 19, 2009 8:20 pm

    ~ wrote:The video is pretty good.

    Where my process differs is the amount of oil he puts in and then wastes. It does not need to be at the level of the bleed holes, 50mm above the bottom is more than enough.


    AS,

    As always, thanks for the information.

    Okay, took the bike out today and all seemed okay. I assume because the push rod did not (while reassembling)extend all the way out (about an inch short) something is damaged inside my dampening assembly?

    Just trying to get an understanding of what additional damage I may be causing.
    07 CRF450r
  • PaiNLeSS
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    by PaiNLeSS » Sun Apr 19, 2009 11:49 pm

    Because the damping rod doesn't extend all the way certainly doesn't mean something is damaged, it nearly always means the bleed procedure went wrong somehow.

    I posted this procedure before...

    After your standard bleeding ( refer to manual ), push the damping rod all the way into the inner chamber. Fill the inner chamber with fluid to just below the two bleed holes. With one hand keep the damping rod fully compressed while with the other hand you insert the compression assembly until you feel its made firm and solid contact with the fluid. Then slowly pull the damping rod down. Suction will pull the compression assembly into the inner chamber as you extend the damping rod.

    With the damping rod fully extended, the compression assembly will still lack about an inch from making contact with the threads. Force the compression assembly the rest of the way down with one hand while you're ready with the the other hand, and a 19mm wrench, to thread the cap back on.

    Compress damping rod, check for smooth and full extension, pour out excess fluid from bleed holes.


    This is the technique that I use several times a day and is just ONE of several ways of doing it, but is the most consistent method of getting the job done right the first time.

    It's a little messy, but you can save the excess oil that you pour out the bleed holes.

    An additional note: After you stroked the damping rod enough times and you feel the bleeding part of the job is accomplished, let the inner chamber set for about 3 or 4 minutes to let all the small air bubbles surface and escape.

    Typically after using this procedure you'll actually FEEL the damping rod make full extension when it hits the end of its stroke. You'll know you're in good shape then : )

    So to recap...

    You're overfilling the inner chamber with oil prior to installing the compression assembly. Once the compression assembly is screwed back on, you'll compress the damping rod fully, hold it fully compressed for a few seconds, this will force all the excess oil out and into the compression assembly where the excess can be poured out the bleed holes. Now the inner chamber has the EXACT amount of fluid.
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    kerrycorcoran
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    by kerrycorcoran » Mon Apr 20, 2009 5:35 am

    PaiNLeSS wrote:Because the damping rod doesn't extend all the way certainly doesn't mean something is damaged, it nearly always means the bleed procedure went wrong somehow.

    I posted this procedure before...

    After your standard bleeding ( refer to manual ), push the damping rod all the way into the inner chamber. Fill the inner chamber with fluid to just below the two bleed holes. With one hand keep the damping rod fully compressed while with the other hand you insert the compression assembly until you feel its made firm and solid contact with the fluid. Then slowly pull the damping rod down. Suction will pull the compression assembly into the inner chamber as you extend the damping rod.

    With the damping rod fully extended, the compression assembly will still lack about an inch from making contact with the threads. Force the compression assembly the rest of the way down with one hand while you're ready with the the other hand, and a 19mm wrench, to thread the cap back on.

    Compress damping rod, check for smooth and full extension, pour out excess fluid from bleed holes.


    This is the technique that I use several times a day and is just ONE of several ways of doing it, but is the most consistent method of getting the job done right the first time.

    It's a little messy, but you can save the excess oil that you pour out the bleed holes.

    An additional note: After you stroked the damping rod enough times and you feel the bleeding part of the job is accomplished, let the inner chamber set for about 3 or 4 minutes to let all the small air bubbles surface and escape.

    Typically after using this procedure you'll actually FEEL the damping rod make full extension when it hits the end of its stroke. You'll know you're in good shape then : )

    So to recap...

    You're overfilling the inner chamber with oil prior to installing the compression assembly. Once the compression assembly is screwed back on, you'll compress the damping rod fully, hold it fully compressed for a few seconds, this will force all the excess oil out and into the compression assembly where the excess can be poured out the bleed holes. Now the inner chamber has the EXACT amount of fluid.


    Excellent information. wish I had this a few days ago.

    I love htis forum and the knowledge you guys have!!!

    Appreciate the help. Now, I'll be breaking down the forks AGAIN ;) Live and learn I guess.

    I can't help it, I think wrenching on these things is as much fun as riding - trust me, if you saw how bad I ride you'd understand. :lol:
    07 CRF450r
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    kerrycorcoran
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    by kerrycorcoran » Sun Apr 26, 2009 1:06 pm

    okay i followed the steps you provided...a little better results this time.

    this time when i compress the damping rod it springs back "almost" all the way...still short about 1/2 inch.

    I re-did this step three times to ensure i did it properly.

    does this mean the internals of my damping assy are damaged? or is this configuration okay?

    thanks,
    kerry
    07 CRF450r
  • PaiNLeSS
    Posts:21
    Joined:Mon Apr 18, 2005 9:24 pm

    by PaiNLeSS » Sun Apr 26, 2009 4:10 pm

    kerrycorcoran,

    I have to do it everyday, and still don't get it right all the time. Most of the time, but not 100% of the time.

    I noticed using the method I've described that if something goes wrong, it's usually a little sloppiness on my part, and I have to do it again.

    Thing to remember...

    After bleeding, push damping rod all the way into the inner chamber.

    Fill with fluid to just below the two bleed holes.

    Hold damping rod all the way in as you install the compression assembly.

    Push compression assembly in until it's made firm contact with the fluid.

    Slowly pull damping rod to full extension.

    Compress and thread compression assembly on

    Compress damping rod all the way and hold compressed for a few seconds.

    Make sure the damping rod extends completely on its own.

    Drain excess oil from bleed holes.
  • PaiNLeSS
    Posts:21
    Joined:Mon Apr 18, 2005 9:24 pm

    by PaiNLeSS » Sun Apr 26, 2009 4:14 pm

    If after a few tries this method still doesn't work, you probably have a worn free piston ( compression assembly ) seal.

    http://www.crfsonly.com/catalog/product_info.php/products_id/3237

    But typically, if you're getting the rod to extend down to the last 1/2 inch or so, it's the procedure and not a seal.
  • User avatar
    kerrycorcoran
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    by kerrycorcoran » Sun Apr 26, 2009 4:28 pm

    okay, the 2nd fork worked PERFECTLY. am thinking there is an issue with the other fork.

    the "free piston seal", is that difficult to repair?

    where is is located? any write ups on this?

    I used the videos (mentioned at the beginning of this thread) to learn the fork seal replacement.
    07 CRF450r

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