1983 xj900 master cylinder

Hello XJ experts.
Does anyone know if a master cylinder from a 1984 fj1100 will work on a 1983 xj900 seca? The part #'s are different but both have anti dive and also the cups are different. The cost difference is suprising, $230 for a new xj master and $85 for the fj1100 master. My master is shot as the eye has expired. Any help will be appreciated. Renovating on a budget sucks!!

 

I don't know... but I'm keen to findout as I want to do mine sometime in the not too distant future.

 

I'm not an expert but here it goes. First you would have to make sure they have the same bore and the same thread outlet. I know what you are asking about the part#'s but I am unsure as to the interchanging of these parts. If you want to save some $ I know it is not listed for your bike and they will not tell you if it would work for your bike but you could do a little research and if it works partsnmore has complete master cylinder assemblys for $79. They are listed under xs750/850 and there is al link to and another site mikesxs that has a few other styles to choose from.

 

There are really only two different "size" front master cylinders used on all XJ series bikes, and the variances have to do with:

- the diameter of the piston bore, 12mm (about 1/2") bore used on most single disc brake models (XJ550, XJ650 Maxim, and, surprisingly, also on XJ650 Turbo models) and the larger 16mm (5/8") bore used on all the other dual-disc bikes.

- within each "size" master cylinder, there are differences in whether the fluid outlet port (where your brake line attaches) faces forward (towards the front of the bike) or sideways (towards the centerline of the bike).

- There may be other very minor differences, but that's about the sum differences in master cylinder designs for these bikes.

- Except of course for the 750 Seca master cylinders, which were made on Pluto.

- Fluid reservoirs are about the same size across all m/c's, with the dual disc master cylinder reservoirs being slightly larger in capacity.


By the way, the cloudy plastic viewing window can be replaced with a glass insert:

mc2) While you're rebuilding or even replacing your front master cylinder, you might as well go ahead and replace that dull, clouded, cracked thick plastic sight "window" that allows you to see the level of brake fluid in the reservoir. The original "transparent" round plastic window ages neither gracefully nor well over time, and becomes cloudy within a a few years. Our replacement flat mineral glass windows are the correct size, they won't ever get cloudy, and are one of those small details that you can step back, look at, and say to yourself: "Kewl".

Okay, all that's the good news. The bad news is that the old plastic seal can be a beast to remove. Sometimes, they come out all nice and easy. Sometimes, you have to struggle, and do as that classic old Pink Floyd song suggests: "One of these days, I'm going to cut you into little pieces......". You get the idea. You'll have to fight, struggle, and then win. Clean out the edges of the bore exceedingly well, and make sure that all remaining pieces and remnants of the old window and adhesive are gone before gluing in the new window.

And while you've got that old sight window out, go ahead and dig out the thin aluminum disc that lives right behind the sight window, and which restricts the view of the fluid in the reservoir. Although this disc never wears out, it does hinder you from getting a good view of the fluid level. Again, just carefully pry it out.

Finally, you'll need a good quality adhesive to install the new sight sight glass into the cylinder body. Although there are probably lots of brands of gasket-maker/sealant material that will work, we've found one that is black, easy to work with, and is impervious to brake fluid (NOTE: if you're going to try to use some gasket material that you have sitting around, make DARN SURE that you test it to see whether brake fluid attacks it or prevents it from hardening (almost none of the major gasket-maker materials have been "tested" by their manufacturers against brake fluid, since you do not normally ever use gasket-sealant material in a brake system).


HCP1074 Front brake master cylinder Glass Fluid Level Sight Window, correct size and thickness crystal-clear mineral glass. Each:
$ 5.95

HCP3120 Aftermarket black Gasket Maker, 3.8 ounce squeeze tube. Enough to do about ten thousand sight glasses! But it's the smallest size offered. I'm sure it works well in other applications. Each:
$ 5.50

 

well, THAT explains a lot! :mrgreen:

 

Hello and thanks for the information. How do I aquire a sightglass and the adhesive chacal? Thats all I need sans a rebuild kit. That will save me a ton of $ Thanks again for the information, dano