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I see this anti dive shim on ebay it goes in left shock and works off rear brake and restricts flow to shock.Do these things work or is it snake oil
 

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Just for clarification

The anti dive valve is an existing system that is already in place on the 1800. The purpose of the shim is to disable this system for those that wish to do so and the shim works very well in disabling it.
 

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so does a nickle with a hole drilled in it!!
 

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What benefit is there to disconnecting the anti dive function. It should only come into play when brakes are applied. Am I correct or missing something:shrug:
 

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If you are talking about this one....

http://cgi.ebay.com/ebaymotors/GL18...rcycles_Parts_Accessories&hash=item35b55557d1

It is put between the top and bottom portion of the anti-dive housing and creates enough space between the two to disable the anti-dive function. I installed one on my 2008 after upgrading the suspension and it works as advertised.
I bought the shim and the correct bolts that it comes with. Works good IMHO. I also upgraded only the springs and fork oil with the Traxxion 1.2 kit. :yes1:
 

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The responses here so far have been 'all or nothing", but here is some information that is a sort of "tune it" mod for 'one' of the issues that people may be having with the ATD system, that being it locking up for a period of time after hitting a bump with the rear brake on.


See: http://www.goldwingfacts.com/1800antidive.htm

The thing about doing anything is you can always remove what ever you do by simply removing the front fender and two bolts/screws.
 

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40 plus years of riding, but new to the Goldwing. My brand new bikes unit was stuck on.... Very harsh ride of course! Had it fixed, and my opinion, and it is JUST one opinion is as follows:

I LOVE the idea of anti-dive. Essentially keeps weight of the bike even on both wheels when braking, theoretically making for better tire contact and shorter stops. Also know these systems are prone to sticking. Noticed on the wing that coming to a stop, the anti-dive did it's thing. That is, it blocked the left fork from compressing. This (For me) made for harsh stops at lights etc. Found myself quickly jerking my feet down from the pegs as the bike came to an 'abrupt' stop. Also, when in corners with washboard/ripples, or even straight line under hard braking with washboard surface, again the anti-dive did it's job, stiffened the forks and caused (on more than one occasion) the front tire to 'wash out'. Especially when wet or when there is sand/gravel present. I read EVERYTHING I could find...pro and con, street riders and professional racers, before taking a chance on the shim. The one I bought came with a money back guarantee, so figured it was worth a try. I installed it and find my stops are much smoother (The wife noticed too) and in those same corners, the front forks now can absorb the ripples and KEEP THE TIRE IN CONTACT WITH THE ROAD.
Again, this is only my personal, recent experience with it.
I love the thing and will keep it on my bike.
 

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The early year model GL1800's had Anti Dive (AD) valves that stuck sooner or later. They stuck in the "on" or locked postion. The problem appeared to be original manufactur with "O" rings that were imcomatible with the either one or the other of the two fluids involved, brake fluid and suspension fluid. There has been some mention that the later year models had that corrected. Hopefully so.

There is occasional mention that keeping the brake fluid changed annually or every 12,000 miles (twice as often as the spec) keeps the valves functioning as designed; I don't know about that, it sure did not help the early models.

There was once a popular mod where a thin shim was used at the top nut of the valve to lessen the sensitivity or pre-load of the AD; yet not disable it. Since they eventually stuck anyway, that mod was pretty much frivolous.

Then the thicker shim between the two halves of the AD assembly became popular as a method to eliminate the AD function and still have the option to restore it later, although restoration is probably seldom done.

In the OE set-up, the front springs are so soft that the curb weight of the bike alone uses-up a major portion of the fork travel. Then, as riders get on and the cargo is added, the remaining fork travel is almost nil. Even without the brakes being applied, the bike is almost at bottom in the front, rather small bumps and pot holes slam the front suspension down upon its oil bumpers. This gives a nice cushy ride on perfect pavement and a very harsh one on rough roads.

Honda's AD valve locks the left fork when the rear brake is appied enough to lift the right caliper to acticate the secondary master cylinder. That way the front can't dive any more as the left fork is locked although the right fork is free. Big deal! The bike is so close to bottom anyway it could not have had any significant dive. So the OE suspension ride can suck with the AD disconneced, but suck even worse with it in place.

Thus, lots of us have gone to heavier springs with linear rates instead of progressive rates. We gained significant functional fork travel length in the loaded condition and all conditions. Plus the springs are stout enough to resist significant dive since we ordered them to match our typical loaded travel gross weight. If we leave the AD in origianl form, it will lock the front fork when we apply rear brake at speed and thwart the function of those nice beefy springs we installed. So we nix the AD and wear big grins. The bike maybe rides a little less cushy or mushy on excellent roadway, but it definitely rides way smoother on typical cracked, uneven, or rough roads and bumps - the good springs soak-up the thumps. Actually, when we are loaded to our spring matched weights, the smooth road ride is still really cushy too.

But, there is more. Some of us get our jollies on occasion by riding steep and twisty mountain roads at a sprite pace. With OE springs, even if the AD is not active, the bike's front suspension quickly hits bottom when we enter a down-hill hair-pin turn (or even a lesser turn). As soon as the front suspension hits that limit of travel, a nasty handling trait is immediately met, UNDERSTEAR or plowing. The bike resists turning and tends to skew to the outside of the curve, NOT FUN! If the AD is intact and we use the rear brake in drag fashion as a stabilizing technique, the effect is the same, only it occurs sooner, we plow into the apex of the curve; again NOT FUN! With heavier springs and no AD function, the bike is not easily compressed to its full limit of travel, and does not lock-up the left fork, thus understeer is seldom seen. Such a set-up on the GL18 and the bike will really grip in steep-sharp turns if the tires are up to the task.

I am no motorbike racer and the older I get the slower I go, but I likes them twisties. So for me, I run the heaviest linear springs Traxxion offers up front and their heaviest progressive rear spring in the rear. I have no AD and I now also use Traxxion cartirdges and the brace. I use Avon or B'stone tires. I rarely, if ever, bottom-out the front suspension; even in emergency braking practice. It suits me this way and the OE set-up was truly DANGEROUS for me!

This is NOT a Traxxion infomercial, Progressive parts or/and, I imagine, RaceTech parts are very workable too.

prs
 

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My 2007 front suspensiion sucked from day one. It was insanely harsh and I am very glad it is gone.

Personally, if I was just disabling the A/D, I'd be sure to put in slightly stiffer springs too. It sounds counter-intuitive, but the stock Honda springs are so weak that they bottom out extremely quickly, which is reason number 2 for the harshness. There is a certain amount of consensus that the stock springs are so weak that disabling the A/D just bottoms them out even more.

When you say shock we are all assuming you mean the left front FORK.
 

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Plan on doing the same as PIGEONROOST...that is, adding linear springs when time/$ allow. I am not a peg scraper by any means! (My Deals Gap avg. speed was somewhere around 25mph - enjoyed just fine!) But think over time especially, I may experience some bottoming with the stockers. So far, so good tho on them.
 
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