New member, new bike

To pick up that point 5T made - my XS, is a 1978 SE and one thing I did not like about it was the 'wooden' brakes, no feel. You squeezed, and the bike slowed down, but barely any lever movement. So in addition to replacing the two-section rubber brake hose with a single run of Hel stainless line, cost me £30, I also replaced the whole master cylinder with an RD250 one, £36. This was money well spent and has greatly improved the front brake feel.
Raymond, I just picked up a ‘79 Special and although I haven’t ridden it yet, I don’t like the feel of the front brake lever. When rolling the bike the brake seems to work fine but I really don’t like the wooden feel as there is negligible movement in the lever to full brake engagement. I’m interested in the assembly you purchased for your bike. Do hoses need to be replaced as well? I’ll start an on line search for the RD250 unit.
 
Bosco, brakes are a bit like meccano - you can replace the master cylinder without changing the brake line or you can replace the brake line without changing the master cylinder. But on an old bike with old rubber brake lines, quite possibly original, I felt a braided steel single run line was a worthwhile investment. Probably find a lot of master cylinders with small diameter pistons and any would do as long as the clamp fits the handlebar. I elected to look for a Yamaha item because other manufacturers use a different mirror thread on the r/h side. At least, I think they do?

But sizes of banjos, hollow bolts and washers sizes are pretty much standardised.
 
Bosco, brakes are a bit like meccano - you can replace the master cylinder without changing the brake line or you can replace the brake line without changing the master cylinder. But on an old bike with old rubber brake lines, quite possibly original, I felt a braided steel single run line was a worthwhile investment. Probably find a lot of master cylinders with small diameter pistons and any would do as long as the clamp fits the handlebar. I elected to look for a Yamaha item because other manufacturers use a different mirror thread on the r/h side. At least, I think they do?

But sizes of banjos, hollow bolts and washers sizes are pretty much standardised.
Thanks Raymond, i Looked on line and there’s lots of options for the RD250. Do you know the piston diameter of your master cylinder?
 
The stock MC bore is 14mm, and that's a bit too large for best "feel" and modulation. You'll want to find something in the 11 to 13mm range. I have an 11mm on my '78 and a 1/2" (12.7mm) on my '83. The 11mm gives more "feel" and modulation than the 1/2", but at the expense of more lever travel. 11mm, 1/2", and 13mm are common sizes but I don't think I've ever seen a 12mm. That's too bad because it just might be the ideal size for us, giving better "feel" than a 1/2" but not as much lever travel as an 11mm.

Yes, you want to change out the brake lines. Most of us eliminate the two piece line and it's splitter and go with one long line. For lower bars, a 90cm line length is perfect. You will want a small angle bend in at least one of the banjo fittings (usually speced at 25° to 28°) and you place that one on the caliper for bleed nipple clearance. A straight fitting works fine at the top. The banjo size is 10mm .....

Df6kM3B.jpg


8drKnvC.jpg


A rubber coated clip from the hardware store can be mounted to the lower triple tree where the splitter used to be for a guide .....

PKlR6YY.jpg


bSwxpn8.jpg


Yamaha used a reverse thread mirror on this side. That's one of the reasons I seek out nice, used Yamaha master cylinders. They have that along with accepting the stock lever and brake light switch. This 1/2" MC on my '83 came from a Yamaha Vision (liquid cooled 550 V-twin) .....

dvchMIP.jpg


This 11mm on my '78 came from an XT/TT225 dirt bike .....

bSPVZ5t.jpg
 
Welcome Willholmania - that is a beautiful bike! In regards to the stainless steel brake lines themselves, I've always had them made locally here in Victoria, BC by a hydraulic hose supplier. They have perfectly matched banjo fittings angles and supplied black vinyl covering for my TX application as I wanted it to appear stock. I chose clear ones for a Honda I used to have. These have been much less expensive than online options.
 
The stock MC bore is 14mm, and that's a bit too large for best "feel" and modulation. You'll want to find something in the 11 to 13mm range. I have an 11mm on my '78 and a 1/2" (12.7mm) on my '83. The 11mm gives more "feel" and modulation than the 1/2", but at the expense of more lever travel. 11mm, 1/2", and 13mm are common sizes but I don't think I've ever seen a 12mm. That's too bad because it just might be the ideal size for us, giving better "feel" than a 1/2" but not as much lever travel as an 11mm.

Yes, you want to change out the brake lines. Most of us eliminate the two piece line and it's splitter and go with one long line. For lower bars, a 90cm line length is perfect. You will want a small angle bend in at least one of the banjo fittings (usually speced at 25° to 28°) and you place that one on the caliper for bleed nipple clearance. A straight fitting works fine at the top. The banjo size is 10mm .....

Df6kM3B.jpg


8drKnvC.jpg


A rubber coated clip from the hardware store can be mounted to the lower triple tree where the splitter used to be for a guide .....

PKlR6YY.jpg


bSwxpn8.jpg


Yamaha used a reverse thread mirror on this side. That's one of the reasons I seek out nice, used Yamaha master cylinders. They have that along with accepting the stock lever and brake light switch. This 1/2" MC on my '83 came from a Yamaha Vision (liquid cooled 550 V-twin) .....

dvchMIP.jpg


This 11mm on my '78 came from an XT/TT225 dirt bike .....

bSPVZ5t.jpg
Thanks for the detail 5T. I’ll begin the hunt! The stock brake lever just doesn’t feel right to me. I’m a bit spoiled by my ‘76 where I have a 17mm master cylinder feeding twin, double piston calipers. It has great feel and modulation and is adjustable too. I’m not prepared to spend too much on this bike at this time.

Had a real quick look and there’s Chinese stuff but the bore diameters were 14-16mm. I think I’d rather find a used 11mm OEM unit. I’ll have a better look tonight.
 
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Yes, well if you're not in a hurry, and patient, you should be able to find a nice used MC. It took a while and some searching, but I eventually scored both of mine off eBay for $20 or less each. Granted, they're not new looking, but neither are the bikes they're on, lol. They blend in well. Finding a nice 11mm one, off a dirt bike, can take time. They take a beating.
 
Morning all. Long suffering Triumph T140 Bonneville owner here, but only until next Tuesday when I exchange it for this '77 XS650. Hoping it's going to be everything I wanted the T140 to be. I don't have time to be a full time mechanic, so the Triumph has to go. Excited about the XS. It's just come back from the States, where it's been in storage for many years. I plan to strip and clean the tanks & carbs, overhaul the brakes, fit new tyres, change the oil and hit the road - hopefully.
Hello Will (if I may) and welcome to our friendly Mad-house!
We are on the whole a great bunch of enthusiasts, all willing to help with advise and encouragement. Even our chosen steed XS650 needs some love and spanner work on occasion. But they are less troublesome than any UK classic. Need help just ask. Show plenty of photos; we like to see the progress.
 
Looks like a good deal. I’ll see if I can buy the brake side by itself. Not worried about matching the sides. Thx
 
That's sacrilege, giving away a Triumph for a poor copy, not to mention, where I live at least, Triumphs are worth a lot more than an XS650. I had two, a 71, First of the OIFs and an 82 OIF Bonneville. Both were highly modified and I won shows with both, despite riding them to work everyday. The 71 leaked from the primary chain adjuster due to a bodged repair by the previous owner. No oil leaks anywhere else and it never let me down. The 82 never leaked at all and again, never broke down despite riding it to and from work everyday. Both handled like a train on tracks and had plenty of oomph for everyday riding. Initially, I did have trouble with the 82's push rod tubes, the seal kept on working its way over the hump at the top of the tube, so I turned up a couple of stainless tubes with decent O ring supports at the top. I won The Darwin show around 99 with the 82. The 71 won the Townsville show sometime around the mid to late 70s. If I had had half a dozen XS650s, I wouldn't hesitate to do a swap for a single Triumph. Prepare them right and they are trouble free. Triumph Bonnevilles are probably the most beautiful bikes ever built. Yamaha thought so too so they made a poor copy, the XS650.
 

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