Brake Help. Please!

Chokse · December 31, 2006, 02:09:48 AM

The front brakes on my 95 Magna are feeling a bit soft, so I am going to be doing a light overhaul on them. I have purchased new caliper clips and piston seals, a master cylinder rebuild kit, and a stainless steel brake hose. However, I need some advice concerning the brake pads and rotor. First, what do you suggest I use for the brake pads. I have seen several styles from several companies, everything from organic, to kevlar, to sintered. Not sure what to use and what effect it will have on the rotor. Second, can anyone tell me what the life expectancy of the rotor is? Mine is not warped, but it does have 20,000 miles on it. Could that be part of the problem? If the rotor is still good, is there anything I should do to it that will help improve the braking....should I have it turned, or should I hit it myself with some emory paper? My rear brakes lock up pretty easily, so I don't use them much. As such, I rely heavily on my front brakes and need them to work well. Thanks for any advice you have.

silveradocowboy · December 31, 2006, 08:55:27 AM

Have you tried bleeding them yet? This might be all you need to do unless the pads and/or rotor are worn out. With the parts you have purchased I would go ahead and put them on, never hurts to be safe right. If you are going to do normal street riding the organic pads may be the right ones for you.

Here are some links to some info. but it may lead to more questions...
webBikeWorld: http://www.webbikeworld.com/motorcycle-brakes/
Brake FAQ's: http://www.braketech.com/faq.html
Sintered Versus Organic Pads: http://www.braketech.com/tech/pads.html
Bed-In Procedures: http://www.braketech.com/tech/bedin.html

silveradocowboy · December 31, 2006, 10:29:01 AM

This talk about brakes reminded me of a Kawasaki I worked on last year and wanted to share this experience. The bike had been sitting 15 years with no maint. done to it. The owner said the brakes were not working so I said I would check it out along with some other issues. I have never seen anything like it, the brake fluid turned to powder.

Chokse · December 31, 2006, 10:58:54 AM

I have bled the brakes and put on some organic brake pads, but they are still really soft and stops are slow. I have heard that switching to the SS brake line will help a bit, and the caliper clips, piston seals, and master cylinder rebuild kit were cheap, and certainly can't hurt things. My big question is how effective sintered brakes will be versus the others (I'll read the links provided in your reply above) and how long can I expect my rotor to last? Also, can I help my 20,000 mile rotor by sanding it a bit with some emory paper, and if so, what grit should I use? Thanks for the help so far. I am new to MOOT and have only had my Magna for a few months. I got it for a cheap price because it needed work, and I am trying to get all these little things fixed. I love the bike and I want to get it working well.

MagnaMan · December 31, 2006, 11:28:29 AM

Hi Chokse,

Welcome aboard!

Fluid
First off I think properly functioning stock brakes are adequate. So if yours still feel mushy then the first thing I would suspect is the fluid--especially if it isn't clear. But even if it's clear in the reservoir, there's a lot of fluid in the line and the caliper that could be around since the bike was made in '95.

The service schedule says the entire brake system should be flushed every 2 years or 24,000 miles because the fluid breaks down. There are a couple of ways to do this. You can search the forum here to find them.

You may not need to rebuild the master cylinder once the system is completely flushed.

Rotor
With 20,000 miles on your rotor, I think you should be OK. I haven't heard of anyone having to replace one that early. I don't know about roughing it up with some emory cloth. I've heard some guys do it on the back drum to cut down on the squeal.

I have heard that you want to seat your new pads to the rotor by performing several hard stops when you first put them on.

Other pads
The other pads will provide more stopping power. They will also supposedly wear your rotor out faster. I think most people are happy with stock pads and a stainless steel brake line. So I think you just need to get your brake system functioning properly first.

silveradocowboy · December 31, 2006, 12:34:17 PM

What condition is your rotor in? If it has deep grooves in it have it turned and measure it to see if it is still in spec. It would be hard to say how long your rotors will last because everyone rides so much different but I don't see why you couldn't get 60k+.

Also check the adjustment on your rear brake to see if it has been set too tight, you shouldn't have that in normal riding conditions.

The "bed in" link above mentions useing glass beads to deglaze the rotors. Glass beads have grits from 20 -100 or so so if you are going to sand the rotors use something comparable and clean throughly.

Clipped from the "bed in" link....
Heavy braking should be avoided until the new linings are fully seated across the entire mating surface. A visual inspection may be required. Scored discs will require substantially greater bed-in time, reduce overall stopping power and are potentially dangerous. We recommend replacing badly scored or distorted rotors.

Initially, the brakes should be used lightly (roughly 60-70% of normal) but frequently. As you feel the brakes come in, follow this with progressively harder braking to maximum pressure with momentary cool-down between applications. The goal here is to impart an even transfer film layer from the new friction material to the operating surface of the rotor. Do not try braking hard until they do and you are reasonably certain this is accomplished.

Charles S Otwell · December 31, 2006, 12:59:10 PM

One thing that can cause brake fading on any disc brake is glazing If your brake rotor has heat cracks or is discolored they can be come so hard and slick that it's hard for the pads to grip. you should be able to tell this from a visual inspection.

Greg Cothern · December 31, 2006, 01:06:56 PM

Welcome to the MOOT forum!!!
Great info so far, one spec that I think might be important here is that the rotor thickness limit is 5mm, and I believe they are only 6 to begin with. We have a N. Tex MOOTster who had to change out a rotor, maybe Bob will chime in.

MagnaMan · December 31, 2006, 01:07:24 PM

Jeff, thanks for the links clarifying the "bed in" procedure.

silveradocowboy · December 31, 2006, 05:25:02 PM

No prob Jesse, before this morning I didn't know there was a bedding procedure for brakes

MagnaMan · December 31, 2006, 05:55:00 PM

Well we learn something new everyday don't we, Jeff.

Also, Chokse, if you need a new rotor, www.hondaparts-direct.com has the best prices I've found on Honda OEM items.

Chokse · December 31, 2006, 10:13:04 PM

The brake system was flushed and I am pretty sure there are no bubbles in the system. After bleeding the system, I even loosened the bolt on the upper brake hose where it fits to the master cylinder, as I heard that an air bubble can stay locked in there on the Magnas, and sure enough, some air spit out of that connection. When my braking was still not very good, I began to get some of these replacement parts to get things fixed. Visibly, the rotor looks fine...no deep scoring and no cracks. But, it does look as though it might be worn down to its 5mm limit. I will need to measure to be sure. At this point, if I need to replace it, I am thinking of going with an EBC rotor as it is only $160, about $30 cheaper than the Honda part, and with EBC sintered brake pads. If my old rotor is OK, maybe I'll rough it up with emory paper and go with organic or kevlar brake pads as they might be easier on the rotor. I am also going to do an overhaul of the rear brake as I agree it shouldn't lock up as easily as it does. Again, thanks for all the advice.

roboto65 · January 01, 2007, 04:49:50 AM

I would also say that these are Magna front brakes we are talking about they were never real good anyway the stainless helps but it takes alot of hand pressure to lock mine up. Another thing to look at is have you done your front forks with the progressives that helps too. But once again these are not sport bike brakes and the Magna front brakes are just not that good

Greg Cothern · January 01, 2007, 03:47:02 PM

To improve the Magna braking, I would first, install braided stainless steel hydraulic line. Second, progressive fork springs.
Get a Mity-Mini-Vac to bleed the front line with, any other method is substandard. You attach the Vac to the Banjo bleeder at the caliper, remove the Master Cylinder cover, have someone continue to pour DOT 4 fluid in as you vac out the old fluid. This is easy, very effective and if you keep the MC full of fluid should not introduce any air into the system.
The rear brake I would adjust it to take away some of the pedal to the point on just barely being able to lock it up if you jam it hard.

Chokse · January 02, 2007, 03:55:15 AM

I did a Google search and could not find anything for "Mity-Mini-Vac". However, I was able to find something called the MitiVac Superpump that sells for about $30 and is listed as part # MV6815. I have also found another with the same name and same price listed as part # MV6817. Both say they are universal, so I'm not sure if this is what you are talking about, or if there is any difference between the two. Do you happen to have a model number for the one you use? Thanks.