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General Category => General Discussion => Topic started by: Mike 86 in San Dimas on April 11, 2010, 10:49:00 AM

Title: Anti Dive....agian
Post by: Mike 86 in San Dimas on April 11, 2010, 10:49:00 AM
Ok not really a new topic. In fact some may be tired of this one...anti dive. I am not ready to pull the trigger on the 17 inch wheel. But I am going through the front forks, new springs and emulators from Race Tech. What to do about the anti dive? First thought is, what's so wrong about leaving them? Aside from weight are they a detriment? I not a very knowledge wrencher but can follow my instruction manual. Enjoy canyon riding but not a knee dragger. Just want to improve ride, pretty harsh right now.

Mike
Title: Re: Anti Dive....agian
Post by: andyb on April 11, 2010, 12:18:10 PM
Shortest answer. (http://www.fjowners.com/index.php?action=search)

Slightly longer version:  They're an ok idea, but difficult to implement well, and add needless complexity (read:  more shit can go wrong).  If you're going to the bigger wheel, you can also swap the fork lowers over to a later model or swap up to better still.  You can also rebuild what you have and keep them, or rebuild what you have and block them off.  Don't know that I'd want another potential source of leaks in my braking system though, eh?
Title: Re: Anti Dive....agian
Post by: FJ Flyer on April 12, 2010, 06:16:50 AM
I don't think you can run the anti-dives with the emulators.  You'll need, at a minimum, to drill holes in the damper rods up above the existing one.  Not sure how it plays out with the emulators.  I know others will chime in on the details.  You may need to remove the anti-dives and put on block-off plates.
Title: Re: Anti Dive....agian
Post by: Mark Olson on April 12, 2010, 12:22:56 PM
Mike,

After you drill the dampers out for emulators the anti-dive is disabled.

so it doesn't matter if you leave them in place or not. just remove the brake line and they will be inert.
Title: Re: Anti Dive....agian
Post by: Mike 86 in San Dimas on April 12, 2010, 07:22:29 PM
Read a post by Jeff Hoffman in files section   

http://www.fjowners.com/index.php?topic=526.0 (http://www.fjowners.com/index.php?topic=526.0)

Great post. I intend on replacing the anti-dive units with blanking plate.

Thanks for the replys!

Mike
Title: Re: Anti Dive....agian
Post by: SlowOldGuy on April 13, 2010, 05:35:14 PM
Quote from: Mike 86 in San Dimas on April 12, 2010, 07:22:29 PM
Great post. I intend on replacing the anti-dive units with blanking plate.

AAAAAAARRRRRRRRRRRGGGGGGGGG!!!!!!!

Why is this not clear by now?  Blanking plates will probably leak if you don't get them right.  And it's not just a blanking plate, you have to drill to connect the existing holes in the fork legs.  Otherwise your going to lock up the fork.

If you want to drill something, drill 4 holes at 90 degree angles ABOVE the tapered spindle "step" on the damper rod and be done with it!

Better yet, convert to the '89 front end and see what an FJ is supposed to handle like!

DavidR.
Title: Re: Anti Dive....agian
Post by: Mike 86 in San Dimas on April 13, 2010, 10:36:32 PM
Dave be patient with me. I have been trying to do my home work on this without being too much of a bother to the forum. I have intended on doing the drilling you point out. With help from another contributor I have located a person (machinist) who has successfully made "plates" to replace the anti dive unit, which include machining for the OEM "O" rings.  This is a cosmetic thing. If this guy does not get it right and they leak I could put the anti dives back on.  I intend on following the guidance in the post attachment I noted in my last post. Would you agree with the following section from this post?
"Once the Emulators are properly installed you can either leave your anti-dive assembly in place or remove it and install a block off plate. Normally, when installing a block-off plate, you will need to machine a passage for oil to flow from one orifice to another. However, with Emulators installed you can install a flat block-off plate. The oil passage is not needed, as oil no longer flows through that part of the fork. This procedure is not as difficult as it sounds. Just remember to drill the 6 - 5/16" holes in the damper rod as low as possible, above the tapered spindle."
Sorry for the long post. Mike
Title: Re: Anti Dive....agian
Post by: SlowOldGuy on April 14, 2010, 01:24:00 PM
Mike,
No bother, just trying to get the point across.

I figure you're trying to keep your FJ as stock looking as possible.  I've been there.  I remember wanting to keep my A/D units because that's the way I bought it (original owner).

Do the front wheel upgrade!  This is the single most significant mod I've done to my FJ.  Chris P took one short ride on my '85 and immediately did the same mod on his '87. 

I am still amazed at how much of a difference the 17 inch front wheel makes.  The stock front wheel made the bike handle like a truck.  I had to constantly apply inside bar presure to keep the bike leaned over and if I touched the brakes, the thing always wanted to stand back up.  With the new wheel, the bike floats through corners with almost no bar input.

Do the front wheel mod!

If my YZF600 rear wheel is even a fraction of the improvement the front wheel is, I'll be ecstatic. 

DavidR.
Title: Re: Anti Dive....agian
Post by: doright1 on April 14, 2010, 02:47:26 PM
+1 on the front wheel upgrade!  Totally changed the handling.  I promise you won't be disappointed.
Title: Re: Anti Dive....agian
Post by: rktmanfj on April 14, 2010, 06:44:42 PM
Quote from: SlowOldGuy on April 14, 2010, 01:24:00 PM


If my YZF600 rear wheel is even a fraction of the improvement the front wheel is, I'll be ecstatic. 

DavidR.

I bet you will...      :good:

Randy T
Indy
Title: Re: Anti Dive....agian
Post by: WMarshy on April 15, 2010, 01:32:16 AM
I would take those old forks off your hands if your getting rid of them, they'll make a nice mod to my XS. One mans junk is glory.
Title: Re: Anti Dive....agian
Post by: SlowOldGuy on April 15, 2010, 01:23:16 PM
Sorry, not available.  With this mod you re-use the fork tubes. 

The fork lowers and damper rods are from an '89, but I used my original fork tubes. 

DavidR.
Title: Re: Anti Dive....agian
Post by: FJ Flyer on April 17, 2010, 08:44:53 AM
As the Slow Old Guy, who's not that slow nor old, said, the front wheel upgrade is probably the biggest bang for the buck you can do to the early FJs.  And its pretty damn simple.  Just need some '88 or newer sliders and a 17" front wheel with a radial and either stock '88 or newer brakes or might as well upgrade to the R1/R6 monoblocs (they'd probably be cheaper anyway, off ebay).

As David said, one ride on his '85 opened my eyes.   :yahoo:   As he said, it will go from a pickup truck to a sports car in handling.  

Detailed instructions for the mod are in the Files section.   :good2:
Title: Re: Anti Dive....agian
Post by: Mike 86 in San Dimas on April 17, 2010, 01:11:29 PM
Been away a couple of days. So do you think I should do the 17 inch wheel Mod?.... Got it. It will be on my radar screen.
Thanks,
Mike
Title: Re: Anti Dive....agian
Post by: ccsct203 on April 29, 2010, 09:09:36 AM
I picked up a pair of new anti-dive units in the box on ebay
I did a fzr front end swap so I never installed them.
will let them go for $50 plus shipping. so around $57 total
hard to find new
Title: Re: Anti Dive....agian
Post by: jvb_ca on April 29, 2010, 04:50:08 PM
Quote from: SlowOldGuy on April 15, 2010, 01:23:16 PM
Sorry, not available.  With this mod you re-use the fork tubes. 

The fork lowers and damper rods are from an '89, but I used my original fork tubes. 

DavidR.

David..any issues with using 1st gen tubes in 89 lowers? I picked up a front end from an 89 a few years back and just bolted it up and go. The tubes were in iffy shape at the time, but went with them anyway and now are causing me leaky seals way to quick. I have 2 sets of 1st gen legs and am going to use whichever tubes are in the best condition. I was hoping to be able to use the dampers from the 89 as they are already drilled, and the emulators fit nice and snug in them.
Thanks....Jake
Title: Re: Anti Dive....agian
Post by: SlowOldGuy on April 29, 2010, 06:04:44 PM
Quote from: jvb_ca on April 29, 2010, 04:50:08 PM
David..any issues with using 1st gen tubes in 89 lowers? ...  I was hoping to be able to use the dampers from the 89 as they are already drilled, and the emulators fit nice and snug in them.
Thanks....Jake

Jake,
No problems at all!  I've been using this setup for almost 10 years with no problems.  

I remember lots of consultation with Jeff Hoffman, measuring, and comparing, but everything works fine.  The tubes I received with my '89 forks were less than "pristine" which is what prompted me to reuse the 85 tubes.  The only problem I recall having was trying to reinstall the large washer that fits over the fork seal on the early model forks.  It won't fit on the later model sliders no matter how hard you beat on the fork seal.  :-)

DavidR.
Title: Re: Anti Dive....agian
Post by: jvb_ca on April 29, 2010, 06:56:57 PM
Great to hear. Thanks David. I can see on the parts fiche, the 89's did not have this washer on top of the seal. As long as the wire retainer/circlip thing  holds the seal in place, should be good to go. Will check it out when I take both forks apart apart.
Parts fiche also shows same part numbers for tubes and damper rods.

Cheers..Jake