1982 XJ650 Seca Master Cylinder and Hoses Swap

Hi everyone,

I just got my hands an '82 Seca 650. Its been siting for a while but as soon as I put a new battery in her, it runs like a dream.

The only issue is that the master cylinder is shot. I want to take this opportunity to upgrade the master cylinder and brake hoses.

For the master cylinder, does anyone have any suggestions for a good modern style master cylinder I can upgrade to? One that my side mirror will fit on too? I was thinking of going to a wrecking yard (or ebay) to find a nice used one.

For the the brake lines, I measured mine to be 17.5 inches or 44.45cm. I was wondering if I was to buy two steel braided brake hoses from eBay, that are 50cm each because 45cm is not available, would it work?

I am trying to avoid spending $150+ on the brake lines alone. Any advice would be greatly appreciated!

 

Start a conversation with @chacal

The simplist thing will be to rebuild the master cylinder, brake calipers, and fit braided stainless brake lines.

Any upgrade will require entirely different calipers and master cylinder, as well as mounting plates for the calipers, which will cost you a bit more than rebuilding what you have.

 

Thanks k-moe! I'll reach out.

 

Everything K-mod stated above makes best sense.
I’ll add that the next gen Yamaha master will work also as I believe they are also 5/8 bore and also have the threaded socket for the mirror. I suspect the internals are the same so performance-wise would make no difference. Donors are FZ FJ RZ Vmax Radian etc. Appearance-wise best to keep it stock, your Seca is becoming a favourite.
Anything used should be rebuilt anyway.

The generic brake hoses you alluded to may not have the correct angle fittings, you’re taking a chance there.
I put some eBay hoses on my FZ, 2 hoses directly from the master to each caliper which eliminated the OEM splitter. Doesn’t look great but is hidden by the fairing anyway. I would not recommend that for any naked bike.

 

https://www.z1enterprises.com/ all kinds of brake lines and China's finest master cylinder from ebay for me
two lines and four fittings is cheaper than three lines and six fittings, i use two lines

 

I would use two S/S brake lines. Off the master cylinder you will use a "double" banjo bolt, this will accommodate the dual lines. This will require three copper crush washers one on each side of the lines. This will allow you to eliminate the T block and go direct to the calipers one line to left and right . Saves one less joint, saves a small amount of weight, and gives better braking performance. I use Galfer S/S brake lines as they are also DOT approved. If your calipers are working okay no need to change them? Two cents.
Cheers, 50gary

 

Hey @Polock,

Thanks for the response! Just checked out z1enterprises and it looks like they only have lines for the Maxim models and not the Seca. Would that still work for my case?

-obr

 

Original Style Rubber Brake Line Applications:

bhr1) Reproduction original style RUBBER or BRAIDED STAINLESS STEEL BRAKE LINES, fully and completely DOT approved, with pre-bent banjo fittings and configured for each specific model. These are NOT generic lines and the entire line assembly is DOT-approved.

All of our original style rubber brake lines are made from fully approved two-braid PVA reinforced hose that is compatible with all DOT3, DOT4, and other non-petroleum based brake fluids. These hoses meet all DOT and FMVSS-106 and SAE J1401 specifications, and come fully assembled, ready-to-install with the bright zinc-plated banjo end fittings already pressure-crimped to the hose. NOTE: some models may have originally used yellow-zinc plated banjo fittings, which are no longer available due to environmental considerations.

On models that were originally equipped with the outer coil spring armor, our replacement lines will also have the appropriate black or bright spring-armor installed (this applies to rubber lines; the braided steel lines do not need nor use the spring armor). Caliper lines also come with an attached hose routing bracket rubber grommet that is similar to the original.



Braided Stainless Steel Brake Line Applications:

bhs1) Aftermarket high-performance BRAIDED STAINLESS STEEL BRAKE LINES, fully and completely DOT approved, pre-bent and configured for each specific model. Constructed with a PTFE Type 62 Teflon coated inner tube---therefore making these lines compatible with all types of brake fluid on the market today---and then wrapped with 16 layers of a braided stainless steel mesh, making them the finest quality and safest lines on the market today. These lines truly give you the best braking system enhancement for your money.

Our braided stainless steel brake lines are available with your choice of the protective, translucent plastic outer sheath color: Black (BLK), Bright Blue (BLU), Bright Red (RED), or Clear (CLR). Please note that the Clear (CLR) outer sheathing allows you to see the inner stainless steel braid directly, so that the hose appears like it is "silver" or "chrome".

All of our braided stainless steel brake lines come with the bright zinc-plated banjo end fittings already pressure-crimped to the hose, making the lines ready-to-install, as original. NOTE: some models may have originally had yellow-zinc plated banjo fittings, which are no longer available due to environmental considerations.

On models originally equipped with the outer coil spring armor, these replacement braided stainless steel lines will NOT have such spring-armor installed.....it is not necessary as the braided stainless steel mesh is far stronger and more puncture-resistant than the spring-armor ever was.

All caliper lines also come with an attached hose routing bracket rubber grommet that is similar to the original.

NOTE: because our lines have been designed and test fitted on ORIGINAL BIKES, they may not fit well or at all on bikes that have been modified from original via the use of these different major components: forks, fork tubes, brake calipers, steering under-bracket or crown bracket, handlebars, or master cylinders. Braided stainless steel lines have very little (meaning: "zero") rotational flexing ability, and thus once their end fittings are bent and oriented to a specific application---such as with our lines---there's not much end fitting orientation variance (from original) available----unlike with our rubber lines, which have a much greater range of flexibility to them.


NOTE: we do not have any single-line (master cylinder-to-caliper) replacement lines available. You actually want to keep the stock brake union elbow or joint (on the lower steering bracket) as part of your line system; it is hard steel and doesn't "give" at all (even braided lines have some give to them). Think of it this way: the ideal brake system would be nothing but hard steel all the way from the master cylinder to the calipers......that way, there would be no expansion, at all. Flexible lines have to be used in the real world, though. You want to minimize the use of them, though, so keep any hard steel sections (the elbow).

So while some people believe that they would be better off converting from the original 2-line (or 3-line, on dual-disc bikes) front brake system to a 1-line (or 2-line, on dual-disc bikes) system, thus doing away with the factory joint-manifold-splitter (whatever you wish to call it) on the lower steering bracket, we feel that such a strategy is not an effective solution for a number of reasons:

a) they may not be legal for bikes that are operated in areas that conduct licensing inspections on motorcycles.

b) while direct master cylinder-to-caliper set-ups may be worthwhile for bikes that use very short runs of brake hose---like some modern sport bikes---street bikes, which use much longer lengths of brake line, will experience increased brake line "swell" under pressure due to the additional length of brake line and additional amount of fluid in such a system. REMEMBER, the brake line end fittings ("banjo bolts") and the distribution union ("joint" or "manifold" or "splitter") are hard lines AND DON'T CONTRIBUTE TO BRAKE HOSE SWELL......and thus, if you add up the actual HOSE length between the stock and a direct-line system, you will find that the original style systems actually use a shorter overall length of hose than a "direct to caliper" system!

It may help to think of it this way: the ideal brake system would be nothing but hard steel all the way from the master cylinder to the calipers......that way, there would be no expansion, at all. Flexible lines have to be used in the real world, though. You want to minimize the use of them, though, so keep any hard steel sections (the elbow).

As an aside, the pre-production mock-ups of the XJ750 Seca models actually show a brake line system which is almost entirely hard steel lines, with just a short piece of rubber hose at the calipers. XJ750 Seca and XJ900 models actually use a lot more hard steel lines than other models to "link" the master cylinder to the distribution joint(s), and just like automobiles, the XJ1100 models use a hard steel line from the front to the rear (the XJ1100 models has "linked" front and rear brakes).


Also, please be aware that braided stainless steel lines will give you a much firmer lever feel and quicker, more precise and responsive braking action. You will need to get accustomed to the new braking characteristics of your bike in a controlled manner: practice makes perfect. Trust us---you do NOT want your first real "practice" session to involve a panic stop!


Finally, since stainless lines have almost no "pressure swell" to them AT ALL, it is not uncommon that any brake disc rotor warpage issues.....even minor ones.....that were previously unknown or minor in effect while those old, worn rubber lines were installed, will become HIGHLY NOTICEABLE when you install stainless steel lines. There will no longer be any "swelling, pulsating, deteriorated rubber hoses" to absorb all those tiny pulses of fluid pressure that a warped rotor(s) causes.....and you WILL feel these pulses (in the lever, and in the brake system action) with a stainless brake line installed!


And finally, one final NOTE: all of our LINES (not just the HOSE) is DOT-approved, which is a major difference (and consideration) when purchasing aftermarket brake LINES. For an assembled, complete brake LINE to be DOT approved, each individual, completed brake line must pressure and whip tested, and this is the only meaningful difference that separates DOT vs. non-DOT approval in regards to complete LINES (although perhaps not 100% true, you can pretty much expect any and all brake HOSE to be DOT-approved; but as noted, the hose, by itself, is the not the real issue). You can read in great (and sometimes not-so-polite nor honest) detail about this issue at:

https://www.xjbikes.com/forums/threads/galfer-stainless-steel-brake-lines.40358/#post-353240

 

just search brake line

 

Does anyone have installation instructions for new brake hoses? I am trying to remove my current hoses, but the banjo bolts are blocked from being removed all the way by the fork.
Thanks