Suspension noise question

T_C

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Sonic had suggested I do the 7wt Bel-Ray for more tour then sport riding. It does a good job of soaking up the bumps and not feeling too bouncy.
 

dduelin

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When the fork is assembled it should work as an integral unit. Any damping problem with one side will affect damping as a whole and not affect steering or damping in just the left turns and not the right. Sorry, that makes no sense at all.

The reed valves inside the cartridge are pretty much impossible to blow out, they are going to work or not work, and orifices don't open and close intermittently unless there is trash blocking the orifices. An intermittent problem you describe sounds like the cartridge may not have been bled completely and had trapped air. $150 each for damping cartridges is an expensive way to throw new parts at this problem. If you think the left cartridge is causing a feeling in the left grip then install it in the right leg and see if the problems clear up on the left and move to the right side.
 

mlheck

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I agree with dduelin on this. My Racetech upgrade actually converts on fork to just compression damping and the other to just rebound damping. When everything is bolted together you don't notice this. So I'm not sure that you would be able to feel a blown valve through a particular hand grip or turn.
 
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dduelin

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I agree with dduelin on this. My Racetech upgrade actually converts on fork to just compression damping and the other to just rebound damping. When everything is bolted together you don't notice this. So I'm not sure that you would be able to feel a blown valve through a particular hand grip or turn.
Yes, there are a number of stock suspension motorcycles that utilize one leg for rebound damping and the other for compression.
 
OP
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Igofar
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When the fork is assembled it should work as an integral unit. Any damping problem with one side will affect damping as a whole and not affect steering or damping in just the left turns and not the right. Sorry, that makes no sense at all.

The reed valves inside the cartridge are pretty much impossible to blow out, they are going to work or not work, and orifices don't open and close intermittently unless there is trash blocking the orifices. An intermittent problem you describe sounds like the cartridge may not have been bled completely and had trapped air. $150 each for damping cartridges is an expensive way to throw new parts at this problem. If you think the left cartridge is causing a feeling in the left grip then install it in the right leg and see if the problems clear up on the left and move to the right side.
While I agree with you about the forks working as a whole unit, I believe it would be foolish to swap rods in forks, when I cannot get what I consider the suspect damper to work correctly while on my wrench. I have bled and pumped both cartridges for 10 minutes and only the right damper works as it should. The left one will not draw or push ANY fluid (MMO, ATF, SOLVENT,etc) smoothly.
When something does not work as it should, rather than "trying to get it to work" , I think it's a better idea to simply replace it and remove that concern. It's only money, and cheaper than risking an accident.
 

dduelin

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While I agree with you about the forks working as a whole unit, I believe it would be foolish to swap rods in forks, when I cannot get what I consider the suspect damper to work correctly while on my wrench. I have bled and pumped both cartridges for 10 minutes and only the right damper works as it should. The left one will not draw or push ANY fluid (MMO, ATF, SOLVENT,etc) smoothly.
When something does not work as it should, rather than "trying to get it to work" , I think it's a better idea to simply replace it and remove that concern. It's only money, and cheaper than risking an accident.
Then ignore the second paragraph of my post and concentrate on the first one.
 
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Igofar
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I completely detail stripped both the damper units to see what makes them tick.
The one working correctly was clean inside and out, the left side one, as you guessed had the hole almost completely jammed shut with what looked like aluminum shavings.
I found the rod itself, with a wear mark approximately 4 inches long where it appears to have been scraping while going in and out of the unit.
Could I clean it and get it to work...probably, but you must ask yourself, what caused this wear, and did the wear clog up the works? I'm going to replace the damaged unit.
.02
 
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Igofar
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update: II


After a month long nation wide back order I finally got my damper rods.
I replaced the defective ones with the new units, assembled the forks and put everything back together.
With the new springs, oil, and parts I am pleased to announce the the noisy...the wiggle...the vibration...and all the weird handling issues are gone!
The bike rides better than it ever did!
Thanks to everyone for their help, advice and suggestions.
Igofar

This is what I ended up with as the finished product:
swapped out the 2.1 and installed 1.1 instead
140mm spacer
1 washer between spring and spacer
125mm oil depth
7 wt belray fork oil
Preload set on 14 clicks
Dampening set 1.5 turns
OMG! The 1.1 springs are soon much smoother!
It's like floating on air. No more jarring bumps...rolls into turns now with ease.
 
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