Scandinavian Brake System XJ750 1983

Hi everyone
I have a 193 XJ750 Ex-cop bike with dual disc Scandinavian Brake System.
I have never seen anything like it, it looks like Brake fluid is pumped into the front forks??
Also the forks are air assisted

Needing to rebuild, is there any posts about rebuilding these front setups?

Cheers Mick

 

http://www.xjbikes.com/forums/threads/anti-dive-fork-explosion.41895/#post-380485
those look like seca 900 forks. the brake fluid pushes a piston that restricts the fork compression.
some guys love them, some hate them, some disable them.

 

Yep. Seca 900 forks they are. The '83 750 was essentially a 900 with a 750 engine.

 

Thanks for the info guys

Polock how do you go about disabling these?

 

you could take the banjo bolt from the fork connection and replace it with a solid bolt, then use a single banjo bolt at the wheel cylinder.
if you take the top part of the fork unit off you'll see the piston that gets pushed by the brake fluid. i made these to not push the piston and seal the unit.

i never tried a flat plate that pushed the piston down

 

Just to clarify, the Euro/rest-of-the-world XJ750 models were what we call XJ750 SECA models here in North America, and they did use an anti-dive system, but that anti-dive system is unique to these models.

What is pictured by Myck is a XJ750 Police bike (model 37H), which uses the XJ900 front forking system, which is a completely different anti-dive system, used only on the XJ750 Police bikes and XJ900 models. But also note that it uses the XJ750 MAXIM calipers on the XJ900 fork tubes......a true "parts bin" bike if there ever was one!

 

Mine was disabled when I bought it, here is what it looks like with a block-off bolt I bought from Chacal (virtually invisible because it is flush with the anti-dive casing).

 

That looks like a great idea, Ï will see what type of cover I can come up with

If I was to keep them standard, is there any special way needed to refill these with brake fluid?

Also how many cc of fork oil would these take with the air assist set up?

 

The correct amount for each xj900 fork is 286 ml more or less 4 ml.

 

Bleed the anti-dive units first, then the calipers. Using a vibratory sander to help the air bubbles move back up and out of the master cylinder can also be helpful.

 

Look at that...I don't even have to ask the question, it's already answered. Good Job gents! I'm playing with my '83 Seca this week and ran into the same anti-dive system.