Brake rebuild questions 79SF

[XS1100_OEM4ME]

+1

+1 James, I went from a honda 750 with single disc and rear drum to the XS trip disc, wow, big improvement back in the day. Like I said, not race track brakes, but darn good road brakes when set up right

It doesn't though. The braking system on an XS1100 is perfectly adequate for the performance and the type of bike that it is, I'd say. I bet you didn't grow up with this era of bike, did you? If you've bought an XS1100 and been used to riding modern bikes, no wonder you think the brakes feel "lousy". I think what you mean is "non-modern". It's a different thing and using terms like that to describe aspects of classic bikes isn't really valid, I'm afraid.

Incidentally, it's easily possible to lock both front and rear wheels using the OEM brakes without having huge forearms. The rear is dead easy in particular. As has been said, the whole thing depends on traction of the tyre on the road. Super-dooper modern brakes will stop the wheels rotating better but look at the 'footprint' of an XS11 compared to the huge tyres on modern bikes; there's a lot less square footage in contact with the road.

[jetmechmarty]

Do you folks think there's a bit too much brake on the rear wheel of the XS1100? I recently had two panic stops on the same trip (right of way violations). Both times, I inadvertently locked the rear wheel. I let go immediately to avoid going down. In a panic, it's very difficult to not lock up the back end and set up a high-side accident. I think I was only able to get off the rear brake in time because I feel I am so acutely aware of it. Or, is it just my ineptitude?

Marty (in Leipzig)

[old_skool]

unless they develop an anti locking system for bikes, I don't think there's a bike out there that won't lock up using the rears in a panic stop, so if your competence is in question, so is everyone else's. That's just the nature of the beast, in any braking as you know all the weight shifts forward no matter if you use front/rear or both to stop, no weight on a back tire, I bet if the brakes were half as big, they'd still lock up up in that situation. I think a Mc's should have a modified master controlling front and rear simultaneously and during a hard stop, a proportioning valve sense the change and apply less rear and more front brakes like that of the pickup truck early anti skid braking system.....but then again, I like the simplicity of the way it is now too.

[jetmechmarty]

I think a Mc's should have a modified master controlling front and rear simultaneously and during a hard stop, a proportioning valve sense the change and apply less rear and more front brakes

I have a Moto Guzzi with that system. The proportioning valve is connected to the swingarm. The more the weight on the back, the more the pressure. Did I say that right?

I also ride XS650's. They have a rear drum. It really takes a lot of stomp to lock it up. And yet, it still seems to stop as well as any bike of that vintage.

Marty (in Leipzig)

[GLoweVA]

Didn't one of the MNS models have a proportioning valve? Maybe the 81?

[DeanR]

Do you folks think there's a bit too much brake on the rear wheel of the XS1100? I recently had two panic stops on the same trip (right of way violations). Both times, I inadvertently locked the rear wheel. I let go immediately to avoid going down. In a panic, it's very difficult to not lock up the back end and set up a high-side accident. I think I was only able to get off the rear brake in time because I feel I am so acutely aware of it. Or, is it just my ineptitude?

Marty (in Leipzig)

This is why I put SS lines on the front only when I did mine years ago. I like the extra forgiveness of the stock lines in the rear.

[sthomag]

It doesn't though. The braking system on an XS1100 is perfectly adequate for the performance and the type of bike that it is, I'd say. I bet you didn't grow up with this era of bike, did you? If you've bought an XS1100 and been used to riding modern bikes, no wonder you think the brakes feel "lousy". I think what you mean is "non-modern". It's a different thing and using terms like that to describe aspects of classic bikes isn't really valid, I'm afraid.

Incidentally, it's easily possible to lock both front and rear wheels using the OEM brakes without having huge forearms. The rear is dead easy in particular. As has been said, the whole thing depends on traction of the tyre on the road. Super-dooper modern brakes will stop the wheels rotating better but look at the 'footprint' of an XS11 compared to the huge tyres on modern bikes; there's a lot less square footage in contact with the road.

The stock bike may be "perfectly adequate," whatever that means. What I'm saying is that the brakes work BETTER with a 17mm master cylinder. Not just more "modern." You can stop shorter.

I have made the modification, and I have noted the difference. It works. It allows you to stop harder. It also gives you better feel, and thus more control.

And that means that old skool might avoid a crash if he uses the 17mm master cylinder -- a crash that he might not be able to avoid if he uses the stock master cylinder.

I don't know how I can put that any plainer.

I started out riding bikes with drum brakes, and I still have one: a 1970 Ducati 450 Desmo I have owned for 35 years. I have run bikes with drum brakes, with older disk brakes, with up-to-date Japanese and Brembo disks, and with fancy six-piston calipers. I have noted that there are big differences in performance among them due to a lot of factors, not all of which I understand.

Drum brakes have far more pad area than disks, but they don't work as well. I've noted that the old-fashioned twin-piston Brembos on my old Guzzi work much better with floating disks than the solid disks the bike came with. Why? I don't really know. The fancy six-piston Nissin calipers didn't work nearly as well as the four-piston non-radial Brembos on the same Super Sport race bike, or the radial four-piston Monoblocs on a Ducati Hypermotard that I rode -- both with much smaller pads. The Monoblocs, by the way, with a radial master cylinder and good tires, really CAN throw you over the bars with one finger on the lever. They are what the GP and Superbike racers use, not six-piston calipers with bigger pads.

I've also noted that the new master cylinder gives better performance on my XS11 than the newly-rebuilt stock version. Have you tried this modification? And if you haven't, why are you contradicting me?

I didn't expect to get into a barroom pissing match when I tried to pass on something I had learned to someone who was asking for advice. It makes me wonder what the point of this forum is.

[old_skool]

It makes me wonder what the point of this forum is.

As much as I appreciate yours and everyone else advice, now your just going overboard, besides, only you said someone was giving bad advice, everyone's entitle to share their experience and knowledge, and occasionally there will be disagreements, but its perpetuated long enough!! Everything doesn't have to be black or white. I'm not some kid or someone who's new to riding, just new to the mechanics of the XS11, I was an ASE auto tech for many years, so I don't need anyone's particular point beat into my head. But I still thank you for your very important information. If this continues, I want a mod to lock this thread so I can use it for it's information at a time when I need it, and not get buried in rhetoric.

[crazy steve]

Best advice yet....

[bikerphil]

+1, 19 posts geez.

[sthomag]

As much as I appreciate yours and everyone else advice, now your just going overboard, besides, only you said someone was giving bad advice, everyone's entitle to share their experience and knowledge, and occasionally there will be disagreements, but its perpetuated long enough!! Everything doesn't have to be black or white. I'm not some kid or someone who's new to riding, just new to the mechanics of the XS11, I was an ASE auto tech for many years, so I don't need anyone's particular point beat into my head. But I still thank you for your very important information. If this continues, I want a mod to lock this thread so I can use it for it's information at a time when I need it, and not get buried in rhetoric.

Please accept my apologies. I guess I felt that people were simply sniping, and let my pride get the better of me.

[jetmechmarty]

sthomag,

There are a lot of people reading thase posts that take in the information and have nothing to say. I'm not one of them!

Marty (bored in a hotel room)

[old_skool]

Please accept my apologies. I guess I felt that people were simply sniping, and let my pride get the better of me.

thomas, Thank you, as I said, I still appreciate all the great info you and everyone gave. And its only human nature to get like that once in a while, especially when we feel so strongly about a subject, I did the same thing when someone posted a video of a real butt-head weaving in and out of traffic, and I over reacted, as it was a subject I was passionate about, and I realized I was taking it out the posters and apologize as well. Please feel free to comment any of my post in the future. Again, I can appreciate all points of view and experiences.

[xs11lover]

When you rebuild the masters make sure you clear the sppog hole in the bottom of the well. It's the other hole that doesn't seem to go all the way through until you run a tiny wire through it.
The ss lines made my brakes work waaaayyyy better, but my stock lines were really flexing and bulging. I think I would rebuild the master if it isn't good and hard after bleeding, clean it all and get some good lines.
When you do your forks you can refill them from the bottom so you don't have to rip apart the tops. Also I soaked the fork lowers in really hot water to get the old seals out without much trouble.

[old_skool]

When you rebuild the masters make sure you clear the sppog hole in the bottom of the well. It's the other hole that doesn't seem to go all the way through until you run a tiny wire through it.
The ss lines made my brakes work waaaayyyy better, but my stock lines were really flexing and bulging. I think I would rebuild the master if it isn't good and hard after bleeding, clean it all and get some good lines.
When you do your forks you can refill them from the bottom so you don't have to rip apart the tops. Also I soaked the fork lowers in really hot water to get the old seals out without much trouble.

refill the forks through the damper rod bolt?