[WingWing]

after getting jolted a few times and reading all the posts I decided to deactivate the anti-dive.

Most of the posts say to add a 1/8th inch gap inbetween the two halves.

I added a slightly less than 1/8th inch thickness O-ring in between the two halves.
After compressing the two halves ever so slightly I have, of course, slightly less than the 1/8th in gap ... almost 1/8th but not quite.

Question:
Is the anti-dive valve function "all or nothing"?

By not having "at least" a 1/8th gap will that require more down force before the anti-dive works?

It's pouring here all day so I've not been able to test anything.

thanks,
Dennis

 

[Pigeon Roost]

I recall Max explaining it a bit different than I percieved; I think he said it was all or none. When an AD valve gets sticky, maybe it does help initially to just shim the halves apart a bit, but then it may go sour again. I suggest either a much larger and solid spacer or or just cut the plunger off as close to flush with its half as you can. I do not miss my anti dive, but I did install stronger front fork springs.

prs

 

[Wanderer]

As I understand it, if you shim the bolt with the bleeder in it, it will only delay the action of the anti-dive, depending on how much shim you put in. The shim will make the anti-dive a little less harsh, again depending on how thick a shim you install. The real culprit to poor anti-dive action is the top o-ring. If it's swelled, you'll get irregular anti-dive action, usually always on action because the plunger is stuck in the cylinder. I just bought a new plunger case, which includes the bleed valve, case and plunger. I'd like to coat the upper o-ring with something (vaseline?) so the brake fluid won't attack it so quickly. Anyone know what could be used to coat it???

 

[Cal-D]

By shimming the bleeder bolt you are not delaying the Anti Dive, you are simply removing the pre-load Honda put on the system. The anti dive will still function normally when the brakes are applied. To completely disable it you need to do one of two things. Cut the tip off the plunger or as I did insert a spacer between the plunger assembly and the valve body. This spacer I made from a piece of one inch PVC pipe cut to exactly .350 inch long. Slightly enlarge the inside diameter with a dremmel tool so it will sit down over the raised lip on the body. Then insert it between the two sections and use two 3/8 longer screws to reattach the plunger assembly to the valve. Now the anti dive is disabled and it can be returned to stock if desired in a few minutes. The PCV pipe is the best way to do it in my opinion.

 

[PunkinDave]

I'd like to coat the upper o-ring with something (vaseline?) so the brake fluid won't attack it so quickly. Anyone know what could be used to coat it???

The proper elastomers will not be degraded by the brake fluid.. I believe there was someone here who determined that the o-rings used were not the proper type for this service and would swell over time...
DO NOT USE VASOLINEOR ANY OTHER LUBRICANT!!! It's petroleum based and will certainly swell the o-ring and contaminate the brake system!!!

 

[Fred H.]

1/8th of an inch will probably just about totally defeat the anti-dive. I suggest you ride it and see how you like it.

If Honda had put the proper spring rate fork springs in the bike to begin with, it wouldn't need the anti-dive, but they wanted to try to make the front end real soft, which I believe was a mistake.

If you disable the anti-dive, you will probably also need to upgrade the front fork springs.

Shimming the bleeder valve by one revolution of the valve, removes the built in pre-load and will make the bike ride better but won't affect anti-dive valve operation.

The proper O rings should be EPDM/EPR for use in brake fluid. Do not use vasoline. Silicone grease would probably work, but proper O ring lubricant would be better.

The Honda O rings appear to be swelling and sticking as they age. I don't know what type they are, but I suspect they used the wrong compound. This is a common problem. With new O rings, the anti-dive unit actually works pretty good, if you remove the 1 revolution of pre-load on the bleeder valve assy. Trouble is, even new O rings seems to start to swell and stick pretty fast. I suspect you would have to replace them almost once a year if you really wanted it to work right.

 

[Wanderer]

It's petroleum based and will certainly swell the o-ring and contaminate the brake system.

PunkinWing,

As I've read on this board, the o-rings in the anti-dive valve are made for oil type applications. That's the problem with the top o-ring because it is in contact with brake fluid. The brake fluid makes it swell. Concerning contaminating the brake system, brake fluid is pretty static once it's in the lines. If anything in the AD valve contaminated it, it woud only be contaminated for the first several inches of the AD hose... I doubt it would go any further than that.

Silicone grease would probably work, but proper O ring lubricant would be better.

Thanks Fred. I don't know about o-ring lube but I do have some silicone di-electric grease. I'll probably try that.

 

[REBELEE]

The easy way to dissable the antidive valve is to use a plain old nickel out of your pocket.

Use a drill just a little bit larger than the small part of the activation pin.
Drill the hole exactly in the center of the nickel.
Make sure it will slip over the smallest part of the pin, and drop it in between the two halves of the valve.
Use the same stock screws and put it together.
NOW the pin can not travel into the lower valve and will not activate the antidive valve!
Real easy and you can not even see anything has been changed.

 

[WingWing]

1/8th of an inch will probably just about totally defeat the anti-dive. I suggest you ride it and see how you like it.

thank you for the info.

After the other posts, I put two O-rings in and now the anti-dive IS totally disabled.

I'm sure you're right about the springs.
Overall, I like it better without the anti-dive but under certain conditions the front end feels kind of "loosey-goosey"
... not too technical I know but I don't know how else to describe it
... feels like the front end is just flopping around out there and not connected to the bike
... just sometimes.

I'll probably go back to one O-ring until I get new springs ordered.

thanks again,
Dennis

 

[Fred H.]

Overall, I like it better without the anti-dive but under certain conditions the front end feels kind of "loosey-goosey"
... not too technical I know but I don't know how else to describe it
... feels like the front end is just flopping around out there and not connected to the bike
... just sometimes.

Sounds like you need better fork springs. The OEM spring are just too soft, and your description fits, as soft springs make the suspension feel vague, and will also cause it to bottom out easily.

 

[Turk]

Fred, do you have the dimensions of the shim you made? I think I want to try to remove the preload first and see what that does. Thanks..