Brakes

[Underdog]

I want to do a complete overhaul on the brakes on this bike. First question, is it really nesessary to replace the hoses. The owners manual says to change them every 4 years! These one are 24yo. I don't mind paying for the stainless lines if they're needed to be safe but I'd prefer the stock appearance.
Second, has anyone else used dot5 fluid after a complete overhaul. I've got it in all my old cars and the Harley came with it. I really can't put up with the dot3 paint removal. Thanks.

[Snow]

Have you ever drank a plastic bottle of Pepsi or Coke that had been sitting in the gas station cooler for too long, like maybe a year too long? Now imagine if it had been there for 24 years.
You really should replace your brake lines, whether you replace them with rubber or stainless braided lines. You could always put a rubber coating on the outside of the stainless lines to make them look stock if you wanted.
I believe you can switch to DOT 5 as long as you *completely* purge your brake system, including the calipers and master clyinder. Make sure you have lots of Brake parts cleaner on hand. You might as well go ahead and rebuild the calipers and master cylinder to make sure you get every last drop of DOT3/4 out first. Mixing DOT3/4 with DOT5 is a bad thing. The downside of DOT5 is you could possibly run into vapor-lock.
The nice thing about putting new lines on when switching to DOT 5 is that you don't have to clean the lines first

Note: I have not actually switched to DOT5, I decided against it because of fears about vapor-lock (which may be slightly irrational.)

[Jerry]

Replace the hoses. The original ones will begin to deteriorate from the inside, putting little flecks of 'junk' in the lines, calipers, and master cylinders. They also tend to start flexing more when you apply pressure, requiring more volume (more lever travel) to operate the brakes. Lever feels a bit 'spongy' under these conditions.

The SS lines I put on my XJ have a black covering, and from even short distances they look original. Other colors are available from some sources. Color is provided by a tube or jacket that slips over the SS line before the banjo ends are attached, so the color has to be specified at the time of order.

Have not tried DOT 5, have stayed with DOT, so no first-hand recommendations on this issue.

[randy]

Underdog, if you're looking for S/S brake lines, give me a PM.. Or, check out the threads on Satinless Lines in the Product Evaluations.

Randy

[TopCatGr58]

Hey there Dog,

I did a search and found a couple of links that might be interesting, one which tells how to do the conversion from DOT3/4 to DOT5, and another one that describes the differences betweent them!

DOT5 Conversion technique
Description of Differences Dot3/4 and 5 and 5.1

What Snow mentioned about Vapor lock wasn't described as much as just getting lots of air bubbles in the fluid when it gets shaken and not fully topped off, and that under high temps, the silicone based fluid is a bit more compressible, and with bubbles in it, even more so, so you can get a spongy pedal/lever!!!! It doesn't eat paint, doesn't absorb water, but water can still form/condense and so it settles to the low points still contributing to possible corrosion!

Due to the difficulty of ensuring NO air above the MC fluid chamber, and the inherent extra vibration our MC's see vs. a car, I'm in favor of continuing to use DOT3! HTH. T.C.

[pathfinder]

Dot 5 Yes

I did it 10 years ago with absolutely no problems. If you look at the inside of the front m/c there is a piece of metal right next to the rubber gasket. Mine was all rusty (NOT COOL) the gasket always had water droplets on it again not cool. Advantages, does not draw in moisture, spill on paint and does not hurt it, you could actually rub all over bike and still not hurt paint (Disclaimer: If you have chipped or cracked paint already, it can and will get under it then lift it off). Spooge hole is no longer getting clogged with thick dot 3 or 4 with water in it. Much cleaner to work with. Higher heat threshold. Better braking because it does not collect water which does not compress at the same rate as fluid. My advice is to change to S/S brake lines, front m/c off of a later model Yamaha sports bike and dot 5. It does not make it any easier to bleed, but you don't have to do it very often like you do now. Make sure you get as much of dot 3 out by pushing dot 5 until it runs clean. After it has been in there about a month, push clean dot 5 thru it again to get out what it has loosened up. If you put on s/s line you should rebuild the calipers as you do it. When I installed lines a few weeks ago I didn't, then had to rebuild both front calipers the next weekend. This was because with the upgraded lines it pushed allot harder on the square o-ring in the caliper (they were about 10 - 12 years old) and I got a leak on the left front. If you can afford to do this all at once everything will be new and never had dot 3 in it to screw it up. Another thought never ever put Teflon tape on bleeder nipples as it turns to mush in a couple of minutes then happily makes it's way throughout the brake system sealing things that shouldn't be sealed up. There was an articticle about just that thing in Popular Mechanics in the last couple of months. Just my 2 Cents.

[Underdog]

Thanks, I was aware of the advantages of the DOT 5. I didn't mean to stir up any controvercy over which is better. Just wanted to make sure that there wasn't some idoisycricy with the materials in these bikes that would prevent it's use. I have it in my MGB which I have done track days with at a local road course. There are two long straights with heavy braking zones which cause the brakes to get very hot. I've never experianced any fading or vapor lock with it. I'll be doing the complete system over. I'm sort of a safety nut when it comes to stuff like this.