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I know this subject has been gone over quite abit, however I'm still confused. I think I understand that an ADV frozen in the closed position will give one a harsh ride in the front. My question is, how does one know if it is the valve or something else.

The reason for my question is the fact that I can cycle the front suspension with the front brake applied, at a stand still. Also when coming to a stop the front suspension will cycle, with the front brake applied. The problem is that I still have a very harsh ride, mostly when hitting bumps in the road, like one inch road strips.

What I'm asking is the fact that the front suspension cycles mean that the ADV is good. :shrug:
 

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Good question; does it cycle with foot brake applied also? (I don't know if that affects it or not).
 
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Discussion Starter #3
It's hard to get the front shocks to compress with the back brake even though the front and rear brake are linked. As I understand the process, the ADV will activate with the front brake being applied.
 

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When the AD valve sticks closed, teh forks do not "cycle", they are pretty much locked. But, when some of these valves begin sticking, they can be intermittent. BUT; your complaint and what you notice suggests a different AD related characteristic. The OE AD valves may have a "hair trigger" due to pre-loading. That is, they are set to be pretty close to closed even when open. Fred Harmon proposed and photographed his cure for this, He described using a shim on the top nut of the upper section of the AD valve to decrease that pre-load. HIs photo web page shows the procedure quite well.

prs
 

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The AD will only activate with the front brakes if you actually push hard enough to get the front wheel to roll. The AD is applied from the secondary master cylinder lifting from front wheel rotation while the front brake is being applied. The rear brake applys the AD any time it is pushed. One issue that Fred and I noticed was the apparent preload that exists on the AD from the upper plunger even when the brakes are not applied. You can see this when you take out the 2 bolts holding the upper plunger assembly to the fork leg. The lower valve pushes the upper assembly up about a 1/8" to 3/16" as the bolts are loosened. I believe this preload is slowing down the fluid flow in the fork and thereby causing a harsh ride without the brakes on. Loosen your bolts and go for a short ride, you will feel the difference. I measured the gap that it created and ground off the plunger the same amount. I know I will have to replace this if I ever have a warranty issue, but so far the ride has been smooth and the nose doesn't dive when braking. I did this 4 1/2 years ago and it still works great.
 

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+1 on above. I tested my ADV the same way and found it cycles just fine. If I roll the bike just a tiny bit in the garage, and apply the front brake, you can see the fork travel a certain distance. Apply it again in the next part of the test and it limits the travel of the fork much more. To me, that means the valve is doing its job and is not locked up. But, this is only testing it in the manner that I know.

Fred and many others have more extensive experience in the operation of these valves. I still, for the life of me, can't understand why, Honda, as smart as they are and have the educated engineers working for them at the factory, are still putting out a system like the front forks have, weak springs and some-what faulty valves after all these years.

Apparently, the front fork system is working fine for them but, when it gets over here, and we put it to use on our freeways and side streets, we get some of the most harsh rides one can get on such a finely designed machine. I could be wrong here but, when Dodge, Ford or Chevy finds a fault in there design, after a while, they make a correction 'cause they want repeat customers and they want people to know, they've done their home work and fixed certain problems. Honda, apparently thinks the front fork system is perfect and has not improved it at all in the past years. I'm only speaking from this net as I've only owned an '02, purchased about 8-9 months ago with only 4800 miles on it.

Anyway, not to hi-jack your thread, what it appears is that your test revealed just what mine did and that was the fact that it LOOKS like the ADV is working correctly, again, based on a garage test. :shrug:
Scott
 

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Stones
To cycle the ADV you should bounce the front with the front brake applied and it should cycle several times before locking up. When it locks the suspension, stop moving the bike and release the brake and re-apply it, now bounce the front again. If the ADV is working correctly the forks will cycle again several times before locking.
What you describe is probably related to the ADV. As Pigeon Roost suggests you can remove the Pre-Load on the ADV by inserting a .035" shim under the top bleeder nut on the ADV plunger. Just loosen the 19mm nut 1 full turn and insert a "C" shaped washer that is .035 thick and snug the nut back up. Try that.
Pigeon Roost
For the record, the .035 shim was not Fred's idea.
 

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Stones

What you describe is probably related to the ADV. As Pigeon Roost suggests you can remove the Pre-Load on the ADV by inserting a .035" shim under the top bleeder nut on the ADV plunger. Just loosen the 19mm nut 1 full turn and insert a "C" shaped washer that is .035 thick and snug the nut back up. Try that.
Pigeon Roost
For the record, the .035 shim was not Fred's idea.
Cal-D;

Was the shim idea your puppy? I was not sure it was Fred's,that is why I used the wording "proposed" and such.

prs
 

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Pigeon Roost
Correct, I discovered the ADV pre-load when I first had a problem with my 03 when it was 6 months old and came up with the idea to remove the pre-load rather than disabling it completely as most had done. I discussed it with Fred and he then tried the spacer and liked the difference it made. The rest as they say is history.
 
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