Katana Anti-Dive

[Spirit]

Is there a how-to on improving the anti-dive system? I remember Pierre DesRoches did an article for Cycle (?) and laid it out, but I can't find it now. Anyone got a link back to it? Anti-dive can work, you know....

[busa1300]

I am using a B/King radial master cylinder with my front end (1982).....still has some lever travel, but not as much as the original master.

[Gammaboy]

The anti-dive works by ramping the compression damping right up under brakes - basically turning the front end into an overdamped pile of crap under brakes, resulting in it skipping across the tops of bumps and reducing your levels of grip - not ideal under brakes, and why everyone abandoned it in the late 80s. Disconnect it, put emulators in and move on with life!

I do recall seeing someone do what was basically a cartridge conversion on the internals, but pretty sure that was with a set of Posi-Damps off a GSXR or RG500.

[wraith]

I have gsx750s1 Kat forks on my gs, I've removed the anti dive, made some plates up and put them on. Much better 

It was always said the Suzuki anti dive is sh#t and never worked very well (some would say) 

[johnr]

anti dive is marmite. its part of the experience i suppose. i found that it tends to seize up inside when moisture gets into the space between the two halves. i stripped and cleaned mine and then replaced the circlips with stainless steel circlips. that way they wouldnt seize the pistons cos they wouldnt corode. it worked like that for years afterwards, well in so much as these things ever actually 'worked'

[coombehouse]

When Kat's were raced back in the day the antidive was usually disabled or disconnected as it compromised the already crap brakes & could cause instability. 

[Gilfi]

I'd have to agree that the anti dive is crap. i replaced mine years ago with plates but now here in Switzerland I have to put them on again (and they're not working).

[Dorkburger]

Why do you have to put them on? Is it an inspection thing? If so can you just put them on over the plate with longer bolts and pass it as stock and have it non functioning? 

I have the later PDF units and gutted them when I did the cartridge emulator upgrade. They are there, but do nothing but keep oil in the forks now. 

[Gammaboy]

On 8/18/2018 at 2:29 AM, Dorkburger said:

Why do you have to put them on? Is it an inspection thing? If so can you just put them on over the plate with longer bolts and pass it as stock and have it non functioning? 

I have the later PDF units and gutted them when I did the cartridge emulator upgrade. They are there, but do nothing but keep oil in the forks now. 

Or use a M10 Bolt instead of a Banjo bolt for the line into the anti-dive.

[Gilfi]

Fuckin' hell you guys are great. I think you just might have solved my braking problems.

I'll do this and let you know if it works out. 

[Spirit]

All this sonds really good, EXCEPT, and I'm gonna say it again, Pierrre DesRoches did an article in Cycle years ago where he made anti-dive AND suspension work, and I'm still looking for that. I appreciate that many have disabled it. I appreciate that many feel it is unnecessary. That said, does anyone have a link to the article? 

[Fjbj40]

On my 1100esd I disabled it, put in emulators and straight rate springs and holy shit, it handles amazing. Absolutely no mush and it is so confidence inspiring I find myself pushing it harder and harder every time I drive it!

Pitch the anti-dive shit in the bin!

[Gammaboy]

3 hours ago, Spirit said:

All this sonds really good, EXCEPT, and I'm gonna say it again, Pierrre DesRoches did an article in Cycle years ago where he made anti-dive AND suspension work, and I'm still looking for that. I appreciate that many have disabled it. I appreciate that many feel it is unnecessary. That said, does anyone have a link to the article? 

The way AntiDive functions by definition trades front end grip for reduced dive. Surely the fact that it's not existed anywhere since ~1988 is enough evidence that it's not worth the effort?

[nlovien]

reason why I don't like anti dive ? dam't near shat myself the 1st time I tried getting into a corner whilst hard on the brakes - can really negatively affect how the bike wants to turn in - 

would like to think any worthwhile article on this covers this inherent trait of this device - for me ? thing of the past - at best an elastoplast for other issues, more likely a failed marketing ploy in an attempt to bring a forgotten racing thing into mainstream

[vizman]

win on sunday, sell on monday, crash on tuesday.....

[Gilfi]

Sorry mate, been searching around and can't find anything on the internets

[Askamaskinservice]

Couldn't find what you was asking for, but i found some interesting stuff that might be good.

https://www.motorcycleproject.com/text/stiction_tuning.html

https://biketech7.blogspot.com/2013/11/anti-dive-technology-or-not.html

https://www.motorcyclistonline.com/motorcyclist-archives-1981-suzuki-katana-how-to-lace-wheels-vintage-motorcycle-ads

http://www.yeoldecycleshoppe.com/roadtestlibrary/2016/12/7/1981-suzuki-gs1000s-katana-road-test

 

[Kasuberoa]

Up there, just eventually, for thoses who's been diving... another link to complete with Askamaskinservice

https://www.motorcyclespecs.co.za/model/suzu/suzuki_gsx1100ef 84.htm

Sure most already know this page, but for those who skipped reading the whole thing...

"......anti-dive brake systems, it creates new problems with suspension response. The trouble is that the system can't differentiate between fork movement that results from braking and fork movement caused by bumps, cornering loads, etc. The compression damping can be increased by any major movement of the fork. Unfortunately, you want normal,moderately damped fork response in some of these instances, especially when cornering hard through bumpy turns. With the GS1150, you sometimes get a suddenly stiffened front end that can't respond to bumps and that isn't giving 100 percent to keep the front wheel on the road. Combined with the 1150's mediocre tires, this can lead to sudden slides during fast cornering in a series of stutter bumps or through a gravity dip. Of course, if the bump is big enough and hit hard enough, the system's blow-off valve bypasses the anti-dive damping system. Part of the problem is the difficulty in predicting what will happen. With brake-activated systems, you can simply ease off the brake when you see a bump coming. But with Suzuki's Positive Damping Force (PDF) anti-dive system it is difficult to predict if the anti-dive will activate or whether a bump is big enough to trigger the blow-off feature and bypass the anti-dive. There is certainly little you can do to control it. Some riders found that shifting their weight as far forward as possible put enough pressure on the fork to activate the blow-off system, but the riding position was awkWard and other control problems arose. Varying the anti-dive's settings changes the point where the extra compression damping cuts in and can reduce the percentage of bumps that cause problems, but it doesn't eliminate the situation. Once you have had the front end suddenly stop responding to bumps in the middle of a corner and have felt the front tire skitter, your confidence in the machine is likely to drop sharply.

Fortunately, it should be possible to remedy the quirks of the front suspension or at least bypass the anti-dive system without too much effort. There are also plenty of good sporting tires available to fit the 1150. If we can hang on to our GS1150, we will try to remedy its only major problems and report our results in a month or so.

Looking past the anti-dive's pitfalls, you discover an excellent suspension system, which provides both comfort and control. Altering the fork's adjustments is simplified by eliminating the valve on the 1100 which changed fork air pressure. Rear damping and spring preload change with slick remote adjusting controls on the left side of the bike just below the seat. The rider can easily reach them while riding, and they offer a useful range of adjustments, allowing the bike to adapt to the racetrack and back to the freeway with just a few twists of the wrist. As a general standard, we used the No. 2 settings on the springs at both ends and on the rear shock damping, moving up to the No. 3 settings (sometimes with No. 4 shock-damping settings) for more aggressive passes down twisting roads. We used maximum preload to quicken steering a trifle or shift a bit more weight to the front in an attempt to overcome some of the anti-dive's glitches. Although the 1150 has less steering lock than the 1100, it is still pretty easy to maneuver at low speeds without a lot of dabbing or back strain.

Removing the anti-dive from the braking system has created a much more positive, solid feel in the brakes, which now use double-action calipers like the GS550's, and riveted rotors...."

[jimmyg]

How do I cut out this crap system but keep it on the bike for looks. Exporting the stock standard bike to New Zealand to my son and he says they need it on.

[RGSX]

On 7/6/2020 at 8:16 AM, jimmyg said:

How do I cut out this crap system but keep it on the bike for looks. Exporting the stock standard bike to New Zealand to my son and he says they need it on.

That was my goal, installation of RaceTech emulators eliminates the anti dive feature and you leave the external bits where they are as they're now redundant. Some people remove the unit and replace it with a blank plate but it looks more like Ohlin-ish tech when left in place.

[fab]

20 hours ago, RGSX said:

That was my goal, installation of RaceTech emulators eliminates the anti dive feature and you leave the external bits where they are as they're now redundant. Some people remove the unit and replace it with a blank plate but it looks more like Ohlin-ish tech when left in place.

i have just done this with my katana , really easy to do.

[johnod]

4 hours ago, fab said:

i have just done this with my katana , really easy to do.

I did the same thing a while back HUGE difference.

If you want to get rid of the anti dive completely these are very good.

 

https://tractechmfg.com/product/gs1000-gs1100-anti-dive-by-pass-plates/

[fab]

19 hours ago, johnod said:

I did the same thing a while back HUGE difference.

If you want to get rid of the anti dive completely these are very good.

 

https://tractechmfg.com/product/gs1000-gs1100-anti-dive-by-pass-plates/

thanks for that.

[RGSX]

On 8/19/2020 at 1:24 PM, fab said:

thanks for that.

But why? just apply the cost of that bypass system to Racetech emulators and you'd be better off. The bypass will eliminate the anti-dive but will not improve handling like the racetech emulators will.

My mechanic who spent years tuning on the world super bike circuit says they're an amazing bit of kit and work very well, and that's high praise considering he really dislikes the Racetech owner.

[fab]

53 minutes ago, RGSX said:

But why? just apply the cost of that bypass system to Racetech emulators and you'd be better off. The bypass will eliminate the anti-dive but will not improve handling like the racetech emulators will.

My mechanic who spent years tuning on the world super bike circuit says they're an amazing bit of kit and work very well, and that's high praise considering he really dislikes the Racetech owner.

go back up the page and read what i said , i have done exactly that