What is the difference? HELP???

[Guest]

I am working on a 5/650 conversion and am looking to upgrade the forks. the first photo is what i currently have.
Off of a 81 650


And these are what i am looking at, will someone please explain the difference to me as well as any advantages to using one over the other?

from an 83 550

[hampshirehog]

The 83 forks have anti dive. It was a gimmick back in the day and not worth bothering about. There is a school of thought that a bit of dive will quicken your steering so it's actually a disadvantage. On the bikes I had AD on I never really noticed if I'm honest.

If I were you I would use whichever forks are lighter, especially unsprung. Likely to be the 83 but I've never weighed them. Block off the AD to save a bit of weight as well.

[7981GS]

The newer forks should also have much improved valving, etc.

Daniel

[BassCliff]

Hi,

I've also read here where several members have just upgraded their springs and blocked off (disabled) the anti-dive mechanisms since they seem to have little effect.


Thank you for your indulgence,

BassCliff

[sedelen]

The second set is set-up for anti-dive device when braking. Supposed to keep the forks from going down when applying the brakes. As far as which one is better, well I've read where it takes more lever pressure on the ones with the anti-dive system to get the same stopping power as the forks without the anti-dive system. Some just cap off the anti-dive mechanism and don't use it.
As far as my own personal experience, since I have a '79 GS1000E without the dive mechanism and a '82 GS1100E with the anti-dive mechanism, I don't notice much if any difference at all (Maybe I should check it out more). So, I would believe there is more unsprung weight on the forks with the anti-dive mechanism as I believe they're heavier because of the additional parts. At least that's my 2 cents.

Now if you want to know more and get the complete explanation from the service manual, you can go to BikeCliff's web-site @

http://members.dslextreme.com/users/bikecliff/

and go to the GS1100 '80-'83 T,LT,EX,SZ,EZ,SD,ED/ESD service manual and on pages 14-20 to 14-23 you'll get a detailed explanation of the anti-dive mechanism.

[TheCafeKid]

The 83 forks have anti dive. It was a gimmick back in the day and not worth bothering about. There is a school of thought that a bit of dive will quicken your steering so it's actually a disadvantage. On the bikes I had AD on I never really noticed if I'm honest.

If I were you I would use whichever forks are lighter, especially unsprung. Likely to be the 83 but I've never weighed them. Block off the AD to save a bit of weight as well.

This is true. Many racers use this technique to quicken steering. The dive changes the geometry, similar to raising the forks in the clamps.
I believe it was Kevin Schwantz who perfected and now teaches the technique of being on the gas and on the brakes at the same time to achieve front end dive while keeping the bike up on the rear suspension. Never tried it myself, don't think I would on public roads, as I'm sure it takes a well trained throttle hand and the benefit of having nothing to crash into if you don't get it right away...