1978 Fork Swap to Anti-Dive Forks?

[Old Guys Rule]

I've noticed that some/all of the GS1100/GSX1000e models were equiped with anti-dive fork legs. Can someone enlighten me as to which models and if these forks are compatible (lengthwise and fitmentwise) with the 1978 GS1000?

Do the anti-dive forks make a substantial difference?

 

[Shin-Ken 1074]

I've noticed that some/all of the GS1100/GSX1000e models were equiped with anti-dive fork legs. Can someone enlighten me as to which models and if these forks are compatible (lengthwise and fitmentwise) with the 1978 GS1000?

Do the anti-dive forks make a substantial difference?

Hi, I can't answer your question about which fork set would be compatible however, after riding with anti-dive fitted to my Kat for 26 years I can say from experience that the anti-dive does make a substantial difference, on the poor side of things!

In Feb this year I rebuilt the front end of my Kat:

ground fork tubes and rechromed,
new anti-friction slides,
new fork damper assembly,
new fork seals,
new custom made 5.0mm wire progressive fork springs.

After this work there was a slight improvement in handling and braking but not as much as I had hoped so to test a theory I disabled the anti-dive units.

What a change! The braking and handling improvement is so much better it's like a new bike, no more soft wallowing washed out feel from the front.I don't know why I waited this long to get rid of the anti-dive! One more bonus is now the front brakes bleed so quick and easy with lever pressure starting at 10mm of lever travel, Kat owners will know what a huge improvement that is compared to having the anti-dives fitted. My opinion is don't go through the cost and headache of having anti-dive they are all show and no go, cheers.

 

[salty_monk]

All of the 1100 E models should fit. Use your original triple trees. They are all 31" long. I am in process of fitting some 83 1100E fork legs to my 78 1000E right now. I have disabled anti-dive & fitted emulators though... You get preload & rebound adjust on the 83 forks.

 

[koolaid_kid]

Everyone I know with an 1100E disables the anti-dive, including me. I also disabled it on my 83 GPz. It just works too well, had it been adjustable it would have been O.K.

 

[rwcfrank]

I am trying to put GS1100 forks on my 78 GS750 also. Is it easier to swap bearings or just grind and press the stem out and reweld it? I am struggling with the dimensions on the allballs racing website.

 

[TheCafeKid]

Not positive but all I think you need to do is order tapered bearings for a Gs1100. The steering mast itself I believe to be the same diameter. Only the stem was larger

 

[7981GS]

"It can't be done. They don't work"

Use 7.5-10Wt. fork oil. It works wonderfully.
As designed. :dancing:

Want to see several video's taken over the past year and a half and 7,000 miles? :-\\\


Eric

 

[rwcfrank]

Any explanation why it wouldnt work?

 

[7981GS]

Here's a video. (Allow it to download before viewing)

http://www.youtube.com/watch?v=MEjbD-_AsZM


Eric

 

[TheCafeKid]

In truth, it does work. The problem lies in the fact that two things happen, which causes a third problem. One: it relies on your brake fluid to activate the valve that prevents movement of the fork oil. This can and does cause a somewhat mushy lever feel. Second, the system is prone to picking up gunk and a corrosion because brake fluid is hydroscopic. This can cause, if the system isn't stripped and cleaned on a annual basis, the anti-dive effect to become somewhat unpredictable. Sometimes it will work really well, others not so much, and then sometimes not at all. I played with this system when I had my 1100E and the combo of the crappy lever feel at the brake, and the inconsistent nature of the system drew me to simply disabling it altogether. When I'm pressing a bike hard, I want to know how it's going to respond, every time. If it dives under brake, so be it. In actuality some dive under brake is good, as it shortens the geometry and allows for a bit quicker steering. But to me it needs to be consistent, and that system doesn't provide that consistency.
Suzuki did get it better with the GSXRs electrically actuated valve later..

With the advent of full cartridge fork systems the anti-dive systems found on many bikes of the good ol days went the way of the dodo.

I think, IMO, you'd be better served to use some cartridge emulators and good updated forksprings...
Just my opinion.

 

[tkent02]

One more advantage to the newer forks, they have less friction in the telescoping movement, and so they ride much smoother. Dump the anti dive, use emulators and good springs, and you can have a very nice smooth controlled ride.

 

[Old Guys Rule]

Can you simply swap out the legs (fork bottoms) or do you need the newer tubes as well; are the fork tubes the same?

 

[rwcfrank]

The newer forks are 37mm and my older GS forks are 35mm

 

[salty_monk]

The fork tubes are different from the 1000 ones. They have a different bottom end to allow for the anti dive system & teflon anti friction rings.

Same diameter but the top caps also don't interchange...

Has anyone found a reliable way to block the air holes so you can remove the air clamps & associated pipework?