Anti-Dive fork question

I have a couple of questions about anti-dive forks:

1. I've heard XJ750s have an anti dive system on their forks, which years have this?

2. Will an XJ750 fork bolt up directly to an XJ650?

3. has anybody swapped an XJ750 fork onto an XJ650? Is it worth it?
My bike brake dives like hell. I'm was considering rebuilding the current fork using heavier oil, but thought it might be worth it to swap to a 750 fork.

Thanks

 

I've been doing a bit of reading on this lately.

From what I understand what should really happen in theory:

Calculate the sag of the suspension (front and back) unloaded. i.e. measure the difference in compression of the forks from completely unloaded ( picked up off of the ground ) to sitting under it's own weight. This should be 15-25mm...

Calculate the sag of the bike when you are on it. i.e. the difference in the compression of the forks when you are off of it to when you are on it.

This should be 15-25mm.

You can reduce sag by increasing preload - i.e. a spacer. If you can not get both values into this range then the spring rate would need to be changed. If the sag was too large - a heavier spring rate... and vice versa for too low a sag.

Then using a different oil you can set the dampning? Heavier oil harsher dampening?

All theory that I'm trying to work through that I can't really explain fully yet. I'm looking at getting it right as I'm thinking about buying a track bike in the next few days.

I've got a spare set of zx600 E 41mm forks/triples/calipers/spindle and master cylander if you are interested in a crazy mod

 

Addendum to my orginal post,

Anyone know if 82 XJ650 Seca forks will bolt into 81 XJ650 Maxim tripple trees? Anyone know if the brake caliper mounts are the same?

 

one could grab some vernier calpiers and tape measure and do a trip the the bike wreckers , one could check tube size and whole length / travell , width for streering clamps ect , even wheel axle size , could come up with anything from anything ? only a suggestion

 

I would bet even money that the 82 will bolt right into the 81 with no problems. I do expect that you will have issues with the calipers, the pictures in the Haynes show a very different mounting for the 82 RJ. If you have the calipers and master cylinder from the Seca, you'll be ok. Otherwise, I would advise against the swap.

 

not related but sometimes i wonder , why are triple trees called triple trees when there is only 2?

or is it because duo trees sound stupid or is the vertical shaft included?


good investigating on the fork issue.

 

Well - there are the two forks and the center tube that goes into the head stock... so I guess that counts for the third.

funny name in either direction - why is it a tree?

 

Welllllllllll , maybe the forks "branch" off them so a tree , but that could meen the center tube is the trunk and is part of the tree , soooooooo that could meen the whole forks and clamps? ect is really the tree! ,why do i think of such stupid things .

congrats on da newish bike woot , tis good fun to have a new ride sometimes and to boot the oldy went to a good home