77 xs650 Dual Disc upgrade

vtwinsrgood

XS650 Enthusiast
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Morning/Afternoon All, :p
I ordered up new left/right caliper's and the disc rotors/pads.
In my lack of thinking things through, I didn't order the front brake hose manifold as there will be two discs not one.. Doh!!
Is there anything else I am needing? I am ordering via xs650direct in Canada. Has anyone here ordered through them, or done the same conversion/upgrade?
Thanks in advance!
VTRG
 
Usually, these bikes come stock with that "manifold" or line splitter. It's usually mounted on the lower triple tree.
 
XS77D Canada Parts manual  124.jpg
 
ahhh, I see now. Looks like I'll need the longer dual hose banjo bolt. I had the original single disc/rotor setup.
I'll need to measure hose length to see what I need with clearance etc. LOTS to do in the next couple of weeks.
Rear sets, bars, fork seals,emulators carbs..etc..
Thanks for the insights!
IMG_2745.jpg
 
I haven't used these exact ones but have used others from these Chinese sellers. What you need, and what most of these are, is lines with 10mm banjo fittings on them.
 
If you still have the old brake lines, the lowers for the duals you just need two the same length as the stock lower.
On the upper depends on the bar height. I might get the bars before I ordered the upper line. That way you can install the bars and master cylinder then put the old upper hose on the junction block then run it to the master cylinder. Mark it where it comes to master cylinder, remove and measure.
Leo
 
Are you using oem discs and calipers, or reproduction parts?
The stock (Euro) Yamaha twin disc setup is extremely heavy, and not exactly a great brake setup either.
On my 650D, I lost around 5kg/ 11 lbs of unsprung weight by converting to a single 320 mm disc and a Brembo 4 piston caliper, combined with a 13 mm bore Brembo master cylinder. Weight savings from using an alloy front fender is also included. From memory, the oem discs were between 2 and 2.5 kg EACH, while the 320 mm ISR disc is around 1.4 kg.
I havent used the XS with this new brake yet, but my experience with a similar brake setup on a Ducati 600 tells me it will be way better than the stock setup.
 
The stock components are way overbuilt as far as durability and so overweight as well.
 
Once I'd rebuilt my Euro-spec twin disc calipers I found the standard MC was too insensitive, feeling a bit wooden.
I experimented with a Kwack 14mm MC, and the brakes were fantastic, but the slight amount of lost motion at the calipers translated at the bars into the brake lever moving back uncomfortably close to the bar. I then fitted a 5/8" Deauville MC which is a perfect compromise, providing good feel and the bike stands on its nose without any grabbiness. Standard calipers, new pads and nothing special in there, but the brakes have never been so good.
 
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Yes, caliper/ mc ratio is mostly too low on 70s bikes in general. If one should want to stick to Yamaha master cylinders, the RD 350 mc is 5/8" also, and I suspect the earlier disc brake XS has the same one, as they use the same dual piston caliper. I do not know what mc size a later model with single disc has, but it may work for dual discs as well.
 
On my 78 Special I have the dual OEM lines,rotors and caliper set up but am using the stock master cylinder for the single caliper set up....I find the braking strong,smooth with a very light 2 finger pull....a great mod for any XS IMO
 
Sure looks nice! May I ask what discs you are using? Any spacers required?
like these. https://www.ebay.com/itm/93-94-95-9...062920&hash=item3b0cfc1be8:g:B1sAAOSw9Nha-IzJ
"93 94 95 96 97 98 99 Yamaha FZR600R FZ600R FZ600 Front Brake Rotors" there's other models use them too.
yes they need about 7mm spacers, I turn my own.
front madness 2018.jpg

Yamaha Motorcycle 1992 FZR600RD Front Brake-Caliper

Yamaha Motorcycle 1993 FZR600RE Front Brake-Caliper

Yamaha Motorcycle 1994 FZR600RFC Front Brake-Caliper

Yamaha Motorcycle 1994 FZR600RF Front Brake-Caliper

Yamaha Motorcycle 1990 FZR600AC Front Brake-Caliper

Yamaha Motorcycle 1991 FZR600RB Front Brake-Caliper

Yamaha Motorcycle 1996 YZF600RH Front Brake-Caliper

Yamaha Motorcycle 1997 FZR600RJC Front Brake-Caliper

Yamaha Motorcycle 1998 FZR600RK Front Brake-Caliper

Yamaha Motorcycle 1998 FZR600RKC Front Brake-Caliper

Yamaha Motorcycle 1995 FZR600RGC Front Brake-Caliper

Yamaha Motorcycle 1992 TDM850 - TDM850DC Front Brake-Caliper

Yamaha Motorcycle 1992 FZR600RDC Front Brake-Caliper

Yamaha Motorcycle 1993 TDM850 - TDM850EC Front Brake-Caliper

Yamaha Motorcycle 1993 TDM850 - TDM850E Front Brake-Caliper

Yamaha Motorcycle 1990 FZR600RAC Front Brake-Caliper

Yamaha Motorcycle 1991 FJ1200BC Front Brake-Caliper

Yamaha Motorcycle 1992 FJ1200DC Front Brake-Caliper

Yamaha Motorcycle 1992 FJ1200D Front Brake-Caliper

Yamaha Motorcycle 1992 TDM850 - TDM850D Front Brake-Caliper

Yamaha Motorcycle 1999 FZR600RL Front Brake-Caliper

Yamaha Motorcycle 1999 FZR600RLC Front Brake-Caliper

Yamaha Motorcycle 1996 FZR600RHC Front Brake-Caliper

Yamaha Motorcycle 1989 FZR600W Front Brake-Caliper

Yamaha Motorcycle 1989 FZR600WC Front Brake-Caliper

Yamaha Motorcycle 1995 YZF600RGC Front Brake-Caliper

Yamaha Motorcycle 1996 FZR600RH Front Brake-Caliper

Yamaha Motorcycle 1993 FZR600REC Front Brake-Caliper

Yamaha Motorcycle 1991 FJ1200B Front Brake-Caliper

Yamaha Motorcycle 1991 FZR600RBC Front Brake-Caliper

Yamaha Motorcycle 1990 FZR600RA Front Brake-Caliper

Yamaha Motorcycle 1995 FZR600RG Front Brake-Caliper

Yamaha Motorcycle 1995 YZF600RG Front Brake-Caliper

Yamaha Motorcycle 1997 FZR600RJ Front Brake-Caliper

Yamaha Motorcycle 1996 YZF600RHC Front Brake-Caliper
 
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7mm spacer? You could use an old junk stock disc for that, couldn't you.
 
FWIW, the stock dual disc setup weighs about 20 lbs. I just moved to Mississippi, where the roads are bad. Those heavy wheels, 20 lbs of brakes, and upgraded springs make for an unpleasant ride.
 
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