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Arrrgggghhh!!
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Discussion Starter · #1 ·
I am having some fork issues, and I was hoping to get some help here.

I bought a 2004 Marz Z1 FR SL in December, and immediately noticed that there was a rattling noise coming from the front end of my bike (I changed nothing else) when going over small rocks or chattery sections. I rechecked my install since it was my first and the rattle did not go away. I then tightened and lubed everything on the front of the bike to no avail. I brought it in to the LBS and they could not recreate the problem during city riding, but rechecked my install which they said was fine.

Just last night I spent some time at a trail with lots of little rocks and figured out that if I leave the ECC adjustment open (full travel), I get the rattle. If I close the ECC I still get the rattle until some of the fork travel is reduced (from a large bump or if I put weight into it), at which time the rattle goes away.

I have yet to open this fork up.

Has anyone heard of or seen this before? Any advice on what to do?

Thanks,
Bill
 

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No, that's not phonetic
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Tell us your air pressures in both positive chambers, and also the negative chamber. How much sag do you run? Is the "rattle" just the fork bumping at topout repeatedly? Does it knock when it extends fully? Is the rattle just lots of little topout knocks?
 

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Arrrgggghhh!!
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281 Posts
Discussion Starter · #3 ·
I was running 50, 50, 150 (I'm 225 lbs). I changed to about 40, 40, 135 to get a little more small bump plushness. The rattle did not change with the change in air pressures. I really don't have any sag, as I read was normal for this fork on old posts (maybe thats the problem). It does not make noise on larger rocks, stairs, etc. I never noticed anything when bouncing around in the parking lot that seemed like a topout at full xtension. It could be repeated small topouts (is that something that happens?), I can't really look close while riding without eating it, but I was not looking at that in particular either.

tscheezy said:
Tell us your air pressures in both positive chambers, and also the negative chamber. How much sag do you run? Is the "rattle" just the fork bumping at topout repeatedly? Does it knock when it extends fully? Is the rattle just lots of little topout knocks?
 

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Arrrgggghhh!!
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281 Posts
Discussion Starter · #5 ·
It stays down while riding. I think that it will release slowly if I get off the bike, but I have not specifically looked at that.

14TripleD said:
Does your ECC lock down good, or does it tend to slip?
 

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Arrrgggghhh!!
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281 Posts
Discussion Starter · #7 ·
I'm thinking from going back and reading all the posts out there that this may be a negative pressure/topout issue. Does 180-190 negative and 40 positive sound better as a setup for a 225# rider on this fork? I'll give it a try this friday.
 

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Arrrgggghhh!!
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281 Posts
Discussion Starter · #8 ·
I think the ECC is working fine. I'll double check on the cable as a possibility.

14TripleD said:
If your ECC doens't lock down very good, you may be low on oil.

Could the rattle be your front brake cable rattling on the fork?
 

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My pump doesn't do low numbers well, but on mine I have 30, 30, and 125. I usually weigh in at 200 to 225.

Check the negative chamber for oil leakage. Someone here gave the how-to as turning the bike upside-down and inserting the inflate adapter and see if oil shoots out.
 

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a dad
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2,927 Posts
i had the exact same problem in the exact same conditions you describe on my AM-1...the thing that sucks is not being able to recreate it unless you are on a ride...anyhow, i had it taken apart, changed oil while in there, inspected, found no problems and put back together and its gone...i have no idea what it was but i am glad it is gone, was driving me nuts...hopefully you are mechanically inclined and can do it yourself...
 

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Arrrgggghhh!!
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Discussion Starter · #11 ·
Great! I feel much better now that I know I'm not the only one. It is driving me nuts, and comes real close to sucking the fun out of DH. I hate random bike noise. I guess it is coming close to the time for my first oil change anyways.

billybobzia said:
i had the exact same problem in the exact same conditions you describe on my AM-1...the thing that sucks is not being able to recreate it unless you are on a ride...anyhow, i had it taken apart, changed oil while in there, inspected, found no problems and put back together and its gone...i have no idea what it was but i am glad it is gone, was driving me nuts...hopefully you are mechanically inclined and can do it yourself...
 

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a dad
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BBOC said:
Great! I feel much better now that I know I'm not the only one. It is driving me nuts, and comes real close to sucking the fun out of DH. I hate random bike noise. I guess it is coming close to the time for my first oil change anyways.
if you figure out what it is or was please let me know in case in happens again on mine..thanks
 

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Arrrgggghhh!!
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Discussion Starter · #13 ·
14TripleD said:
If your ECC doens't lock down very good, you may be low on oil.

Could the rattle be your front brake cable rattling on the fork?
Checked on my friday ride and the ECC stays down and it's not the brake cable.
 

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Arrrgggghhh!!
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281 Posts
Discussion Starter · #14 ·
BBOC said:
I'm thinking from going back and reading all the posts out there that this may be a negative pressure/topout issue. Does 180-190 negative and 40 positive sound better as a setup for a 225# rider on this fork? I'll give it a try this friday.
Increasing the - pressure to 180 reduced it by about 70-80%, but it is still there. I'm going to pull her apart this weekend, change the oil and see if that takes care of it.
 
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