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Disabling the anti-dive valve 101

103K views 97 replies 65 participants last post by  paulcf  
#1 ·
I have been getting some PM's asking how to disable the anti dive valve, so I thought I would share this with the class.

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If you want to totally disable the anti-dive, you need to separate the upper and lower halves of the anti-dive valve by about 1/4 inch. All you need to do is loosen the two allen bolts that hold the two halves together, and put something between them (washer? large O ring? nickel with a hole drilled in it?) to hold them apart a bit, and then put it back together.

In this (out of focus) picture, you can see the two halves separated. After you separate them, when you look at the bottom side of the top half you will see a small black piece sticking out of the bottom. This is the plunger that moves to activate the lower valve. All you are trying to do is prevent that plunger from activating the valve in the lower half of the body.

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Some folks have just ground off about 1/4 inch or so off the black plunger that sticks out the bottom of the top half of the valve, though I don't really like that approach, since it is more permanent and means you would have to replace the upper assy to undo it. However, this approach is an easier fix, as all you do is grind or hack off the bottom of the plunger and reassemble. If you don't mind making it a permanent modification, then this is probably the simplest way to disable it.

Here you can see the top half of the valve is removed, and you are looking at the lower portion of the valve still attached to the fork leg.
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Do not remove the lower portion of the anti-dive valve from the fork leg. If you do, all the fork oil will come out.


The other method I have employed with some sucess is instead of totally disabling the valve, just removing the pre-load that the upper valve puts on the lower valve when at rest. To do this, all you have to do is back off the large bolt assy that the bleeder valve is screwed into by ONE revolution (and only ONE). Then insert some sort of shim or washer to tighten it back down on. When you are done, the bleeder valve assy should be backed off one revolution. This will remove all the pre-load, but will still leave the anti-dive valve functional.

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More photos here:

http://www.pbase.com/fredharmon/antidive
 
#98 ·
Fred, went to your website re the maintenance DVD set (which I have) just to check it out. Found your detailed review of the new Goldwing. Wow, lots of issues! I do not like or want or will ever have weight hanging off the rear of the bike like that you have in the photo, that would surely lead to handling issues and be dangerous. For $35K (here) they are definitely not worth it, as one can buy a lovely Miata convertible and be more comfortable and carry more clothing/stuff.
I'm so glad I have a lovely 2003 Goldwing that does all I ever need it to do and returns to me up to 57 mpg so my average touring range is in the 270 miles on a full tank.

Ride safe!
 
#97 ·
Ok, I have a 2003 GL1800. I rebuilt the front forks, new oil, Progressive Suspension springs (about 2" longer than OEM saggers) and seals.

Ride is horrible, rough, crashing, jarring, and I'm afraid it's going to bust my fairing and my saddlebags will fall off. Got that picture?

HOW EXACTLY do I (should I) go about doing what to disable the Anti Dive? WHAT DO I NEED TO DO?

Thanks!
 
#96 ·
My results in improving my ride

First of all this is not intended as a marketing thing. I installed this item this morning:


http://www.ebay.com/itm/231525961423...%3AMEBIDX%3AIT


Installation is so simple that it doesn't even require instructions. It is absolutely amazing what it does to the ride of the bike. Totally smooth and like riding on an air bag. I went on a long ride this morning as a "before" installation to see if it really made a difference. I returned home, installed it and went on the same ride. It is like night and day and if it saves me a fork seal even more the better. Under $18 delivered.
 
#94 ·
#91 ·
#86 ·
what i am thinking then is to seperate the 2 halves by the 2 allen bolts. then drill a hole into the middle of a nickel, then place the nickle between the 2 halves where the little plunger rests then bolt back up.


this is what i did and that solved my harshness problems. The bike feels as it should now. thanks for the info guys.
Also i think it was mentioned about a 7/32" drill bit and i think that that was one size too small. I drilled a nickel at that size and it would not fit around the little plunger sticking out but the next size bit did. There is now a small gap between the 2 halves.
michael
 
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#85 ·
It just seems to me that if you disable the AD, that, in an emergency, you reduce your maximum braking traction by some unknown quantity = could be unsafe.

In otherwords, when the front end "dives" it removes braking traction from the rear tire that cannot be transferred to the smaller front tire.

Thoughts on this would be appreciated; where is David Hough when he is needed?
 
#84 ·
I found something interesting

I rebult my forks at 94,000 miles. At 105,000 I had an instantanios and complete left fork seal failure hitting a medium sized pothole. I got the fork tube off and pulled the dust cap. The seal was completely blown out! So much so that the thin spring on the inside of the upper side of the seal was 1/2 out and the seal had the ring clip wedged into the slider. I destroyed the ring clip trying to get it out. When I got the fork tube out the upper bushing was sprung about 1/8th inch sideways, now how did that happen (see photo)?

While cleaning up the parts I removed the lower section of the anti-dive valve and while blowing the cleaner fluid off I noticed the fluid wasn't blowing out of both holes. Now I inspected the valve closely, it was frozen shut! That indicates to me that I didn't have the problem most worry about, that being the drive pin stuck down, but the valve itself was jamed shut! It seems to me that fork tube has been locked up for sometime. After some work with silicon lubricant I've got it working freely again. The photo shows the lower section of the antidive valve frozen shut (if you look at Fred's video you can see about 1/8" between the valve parts.)

Now I hadn't cleaned the fork oil on the bike for 94,000 miles until I had a seal fail (MY BAD !!!) so I expect that caused the problem in the first place but nothing I'd read suggested checking that valve for proper operation. Now I know.
I had all the new rebuild parts but now I have to pick up a new spring clip to finish.

It's going to be interesting to see how it feels when back together.
 
#83 ·
Going to bump this thread to the top as i am sure this is whats going on with my 05.
really harsh ride up front.
so if i am getting these 3 or 4 differant fixes right, what i am thinking then is to seperate the 2 halves by the 2 allen bolts. then drill a hole into the middle of a nickel, then place the nickle between the 2 halves where the little plunger rests then bolt back up.
think i got that right.
Michael
 
#82 ·
Anti-Dive Shim

I just installed the ADV shim purchased online (not WingStuff). Inexpensive, quick and OEM-look to this fix. Now the bike rides as a Goldwing should, less harshness but responsive. I would note however I would not have done it without having the progressive springs installed up front as this provides better suspension for the front versus the OEM front springs.
 
#79 ·
After reading through all this it makes me wonder why Honda moved away from the antidive system they used in the GL1200 models... You could choose between 4 different dive settings so everyone could "adjust" to their liking... It was real easy to do as well, just turn an adjustment screw on the side of each fork...
 
#78 ·
I'm bumping this back to the top for another round.
OK, but I'm putting the ball back into your side of the court. Your Big Orange '02 developed a sticky AD valve as I recall. I think your initial approach was to use a slight shim to lessen the pre-load and that such gave some satisfaction for some time, but that the sticky valve worsened and required a full shim which served until you got Traxxionized, end of problem. Is that generally accurate?

Now, there is some theory pronounced on this board to the effect that if we simply do our scheduled brake fluid exchange services, the AD problem would be avoided. I am not at all sure if this theory is valid regarding later year model GL18, but I am pretty sure it is INVALID regarding earlier wings such as your beloved Big Orange and my Basic Black. What say Ye? Wish to opine on the relationship of neglect of brake fluid replacement to sticking AD?

I tend to agree with those who proclaim the AD system to be a bandaid remedy for an overly lax front suspension and that with even modest suspension upgrades, the AD valve is not necessary or even desirable. Further, even with the stock suspension, once the fork springs begin to deform or "sack-out" the available compression travel in the forks is so small that the bottom of travel becomes the "AD".

prs
 
#76 ·
57k miles, stock springs and the tiniest ruts in the road felt like driving over cobblestones. It just got that way in a day or 3. Thought, "it can't be that simple," but I put a washer between the two ADV halves. After a run around the block, it felt like I have CT's on both ends, smooooooth.

I'm about out of funds until after a big trip to Washington from LA next month, so either I drop the bike off at the dealer's or leave in the washer and ride it. Since it's my daily driver, I guess the washer wins. I'd like to get some progressives later this year but we'll see.

I did notice dark smudges on the left fork tube above the seal, not wet, more like scored. I always wonder if that extra pounding on the left side isn't bad for the seals.

Will replacing the fork oil help the ride at all? Even with stock springs? :confused:

I'm ashamed to say I have never changed it in those 57k miles.
 
#74 ·
Fred...did you do this on your new bike?
I sent my forks off to Traxxion Dynamics when the bike had less than 1,000 miles on it. They permanently disable the anti-dive when they rework them.

With the proper spring rates in the front forks, you don't need the anti-dive system anyway, so I never missed it, and I'm glad it's gone.