changing to dot 5

[dolilind]

whats to best way you all can come up with to clean out the dot4? Putting new lines in so that will hepl but the master cyl.,brake pistons how your supposed to do that.
My plans are to bleed down the whole system with a brake vac, change over the line let the tanks and calpiers bleed whats left out, then fluch the whole system with some new dot 5.

Should i spray it all out with some brake cleaner? or that gonna tear up the seals?

[DropBusa]

Why bother with it? Whats wrong with dot 4?

[Jimshog]

Dot 4 eats paint, Dot 5 doesn't. BTW, I did this last winter on mine when I swapped out my brake lines and rotors. I pretty much just drained the master cylinder(s), squeezed the caliper pistons back into the bodies (installed new pads) and wiped everything as clean as I could. Then I installed the new lines and bled the systems (I did my clutch also). The vacuum bleeding process gave me a pretty good flush and I haven't had any problems with the systems since. Note, I didn't have any problems to start with fluid-wise, just lousy brakes (stock). Good luck.
-Jim

[roadthing]

[B]WHY?[B]
Switching to DOT 5 is not necessarily an improvement.

Yes, DOT 5 will not typically harm paint, plastics, etc. True also, that it won't absorb moisture. Yes, it will last longer in your brake system. Yes, it has a good boiling/freezing differential. There's a couple of other benefits, I'm sure.

But wait a minute! DOT 5 is silicone based, and therein lies a little flaw. Silicone defies the laws of physics (well, at least it bends them a little). Liquids do not compress, as you probably already know. Silicone, however can emulate fluid compression, in that it a given volume of silicone can be made to occupy a smaller space.

What does that have to do with your clutch, or brakes? Well, it's simple. Under hard braking, especially when your fluid has become hot, something awful can happen. Let's say that you panic brake, your brake pads, rotors, and fluid is hot. You squeeze the lever to the grip and...that's right, you don't stop. Why? The silicone based DOT 5 has compressed, and you could not supply enough fluid past the piston to push the caliper pucks against the pads to squeeze the rotors with enough force to effect a stop. To get out of that situation, you would have needed a force-multiplier, or a master cylinder with a re-sized bore.

DOT 4 is uses glycol. Glycol can ruin plastic, paint, certain types of rubber. DOT 4 also should be replaced in your clutch, or brake system every two years, as it will absorb water, and that ruins hydraulic systems. But, DOT 4 behaves according to the laws of physics. That's a real plus for us bike enthusiasts. What DOT 4 will do, is give you a very good feel for your brakes. Since it does not compress, it is predictable. Your brake feel will be positive at the lever. As we have only two wheels on the road, positive feedback from our brakes (or hydraulic clutches) is imperative.

If you want to REALLY make an improvement, I would suggest braided lines, and a combination of pads and rotors that "hook" better than stock. If you want to really go nuts, radial master cylinders, and some high-end calipers, such as Brembo. What fluid would I recommend...personally, I'd stick with the DOT 4.

Have a look at what lots of other manufacturers, both car and motorcycle, are using. Even Harley-Davidson finally stepped up and uses DOT 4 (Brembo calipers too). You'll find the majority of brake systems out there use DOT 4.

If you do decide to go forward and switch to DOT 5, I would suggest changing ALL the rubber (Buna-N, Nitrile, etc.) in your brake/clutch system, as well. The longer your rubber parts have been exposed to DOT 4, the less likely they will be to happily accept DOT 5. Your o-rings, seals, etc. can become swollen by the addition of DOT 5, or even become soft, and disintegrate. I would STRONGLY suggest that you do a full rubber swap if you do the switch, as a brake failure, or leaks are a real bummer.

[Aquaman]

I use the Motul DOT 5.1

[Mr Bogus]

you can go with dot5 (and yes in many ways it is a better fluid) but you can have other issues (been there done that) the biggest issue is that of moisture... it will pool at the lowest point in the system..

If you disperse a couple drops of moisture throughout the entire brake system vs. just in the caliper (and that is where it will be) which is likely to boil first from moisture? DOT5 is better fluid yes, but it needs a strict service schedule and really is not a very good fluid for the average user IME.. (pitted and corroded pistons, pitted bores, and corrosion) I just prefer to keep the water in suspension so I can get it out with a simple flush of the system.. On a brake system that is opened and serviced regularly, DOT5 might have some advantages, but on a daily ridden machine? I will stick with 4


I would not even consider "paint safe" part of an argument for a fluid change..

[vman1300]

I use the Motul DOT 5.1

Best way to go!

Higher boiling point and 100% compatible with DOT 3 or 4. I noticed an a noticeable improvement with this mod.

[BusaWizard]

[B]WHY?[B]
Switching to DOT 5 is not necessarily an improvement.

Yes, DOT 5 will not typically harm paint, plastics, etc. True also, that it won't absorb moisture. Yes, it will last longer in your brake system. Yes, it has a good boiling/freezing differential. There's a couple of other benefits, I'm sure.

But wait a minute! DOT 5 is silicone based, and therein lies a little flaw. Silicone defies the laws of physics (well, at least it bends them a little). Liquids do not compress, as you probably already know. Silicone, however can emulate fluid compression, in that it a given volume of silicone can be made to occupy a smaller space. *

What does that have to do with your clutch, or brakes? Well, it's simple. Under hard braking, especially when your fluid has become hot, something awful can happen. Let's say that you panic brake, your brake pads, rotors, and fluid is hot. You squeeze the lever to the grip and...that's right, you don't stop. Why? The silicone based DOT 5 has compressed, and you could not supply enough fluid past the piston to push the caliper pucks against the pads to squeeze the rotors with enough force to effect a stop. To get out of that situation, you would have needed a force-multiplier, or a master cylinder with a re-sized bore.

DOT 4 is uses glycol. Glycol can ruin plastic, paint, certain types of rubber. DOT 4 also should be replaced in your clutch, or brake system every two years, as it will absorb water, and that ruins hydraulic systems. But, DOT 4 behaves according to the laws of physics. That's a real plus for us bike enthusiasts. What DOT 4 will do, is give you a very good feel for your brakes. Since it does not compress, it is predictable. Your brake feel will be positive at the lever. As we have only two wheels on the road, positive feedback from our brakes (or hydraulic clutches) is imperative.

If you want to REALLY make an improvement, I would suggest braided lines, and a combination of pads and rotors that "hook" better than stock. If you want to really go nuts, radial master cylinders, and some high-end calipers, such as Brembo. What fluid would I recommend...personally, I'd stick with the DOT 4.

Have a look at what lots of other manufacturers, both car and motorcycle, are using. Even Harley-Davidson finally stepped up and uses DOT 4 (Brembo calipers too). You'll find the majority of brake systems out there use DOT 4.

If you do decide to go forward and switch to DOT 5, I would suggest changing ALL the rubber (Buna-N, Nitrile, etc.) in your brake/clutch system, as well. The longer your rubber parts have been exposed to DOT 4, the less likely they will be to happily accept DOT 5. Your o-rings, seals, etc. can become swollen by the addition of DOT 5, or even become soft, and disintegrate. I would STRONGLY suggest that you do a full rubber swap if you do the switch, as a brake failure, or leaks are a real bummer.

+1 There's a reason why it says Dot4 only. Sometimes the R and D guys know more than you.

[Jimshog]

I suspect that the substantial increase in cost for Dot 5 fluid has more to do with Dot 4's use in the Busa's production system rather than any other performance or safety concern from an R&D perspective.
-Jim

[roadthing]

I suspect that the substantial increase in cost for Dot 5 fluid has more to do with Dot 4's use in the Busa's production system rather than any other performance or safety concern from an R&D perspective.
-Jim

No, brother it's not always about cost, but you make a perfectly valid point.

I was angry as hell when the cycle industry began using DOT 4. I thought that DOT 5 was superior. That is, until I started doing some research.

I totally dislike the hygroscopic properties of DOT 4, and I dislike the fact that you need to replace it at least every two years. I do, however prefer DOT 4 from an engineer's standpoint.

Another factor that has given rise to the widespread use of DOT 4 is the increase in the use of ABS systems, both in cars, and motorcycles. You cannot have the micro-pulse effect that ABS needs to use to effectively slow/stop a moving vehicle if you use DOT 5, which because of it's unique ability to compress. The fluid will actually diminish the effectiveness of the micro-pulses. Not good in a life-or-death panic stop.

I know that 'Busas don't utilize ABS, but the DOT 4 provides a better feel, IMHO. Again, I don't see a real issue as far as making the switch, but I would stress replacement of all seals, gaskets, rubber parts in the system at the same time.

[tourbus]

[B]WHY?[B]
Switching to DOT 5 is not necessarily an improvement.

Yes, DOT 5 will not typically harm paint, plastics, etc. True also, that it won't absorb moisture. Yes, it will last longer in your brake system. Yes, it has a good boiling/freezing differential. There's a couple of other benefits, I'm sure.

But wait a minute! DOT 5 is silicone based, and therein lies a little flaw. Silicone defies the laws of physics (well, at least it bends them a little). Liquids do not compress, as you probably already know. Silicone, however can emulate fluid compression, in that it a given volume of silicone can be made to occupy a smaller space. *

What does that have to do with your clutch, or brakes? Well, it's simple. Under hard braking, especially when your fluid has become hot, something awful can happen. Let's say that you panic brake, your brake pads, rotors, and fluid is hot. You squeeze the lever to the grip and...that's right, you don't stop. Why? The silicone based DOT 5 has compressed, and you could not supply enough fluid past the piston to push the caliper pucks against the pads to squeeze the rotors with enough force to effect a stop. To get out of that situation, you would have needed a force-multiplier, or a master cylinder with a re-sized bore.

DOT 4 is uses glycol. Glycol can ruin plastic, paint, certain types of rubber. DOT 4 also should be replaced in your clutch, or brake system every two years, as it will absorb water, and that ruins hydraulic systems. But, DOT 4 behaves according to the laws of physics. That's a real plus for us bike enthusiasts. What DOT 4 will do, is give you a very good feel for your brakes. Since it does not compress, it is predictable. Your brake feel will be positive at the lever. As we have only two wheels on the road, positive feedback from our brakes (or hydraulic clutches) is imperative.

If you want to REALLY make an improvement, I would suggest braided lines, and a combination of pads and rotors that "hook" better than stock. If you want to really go nuts, radial master cylinders, and some high-end calipers, such as Brembo. What fluid would I recommend...personally, I'd stick with the DOT 4.

Have a look at what lots of other manufacturers, both car and motorcycle, are using. Even Harley-Davidson finally stepped up and uses DOT 4 (Brembo calipers too). You'll find the majority of brake systems out there use DOT 4.

If you do decide to go forward and switch to DOT 5, I would suggest changing ALL the rubber (Buna-N, Nitrile, etc.) in your brake/clutch system, as well. The longer your rubber parts have been exposed to DOT 4, the less likely they will be to happily accept DOT 5. Your o-rings, seals, etc. can become swollen by the addition of DOT 5, or even become soft, and disintegrate. I would STRONGLY suggest that you do a full rubber swap if you do the switch, as a brake failure, or leaks are a real bummer.

+1 There's a reason why it says Dot4 only. Sometimes the R and D guys know more than you.

nahh thems r&d guys dont know what they talkin bout,really though seems like there are alot of people who know better than the factory.

[djorgensen3]

I don't know about any of you guys but I have had my rear tire 3 feet in the air stopping quickly. The rear in the air was unintentional. Scared the crap outta me. This was done with all stock brakes. How can it possibly stop faster if the rear end will go skyward already?

[roadthing]

I don't know about any of you guys but I have had my rear tire 3 feet in the air stopping quickly. *The rear in the air was unintentional. *Scared the crap outta me. *This was done with all stock brakes. *How can it possibly stop faster if the rear end will go skyward already?

You would be amazed at how the right mix of components can get you to stop. Actually, the right mix of components will get the wheelsto stop turning. Getting the biketo stop is a matter of skill.

Watch your butt out there with the stoppies. On Sunday I saw a kid on an R-6 do one unintentionally, with a bad ending. He got rear-ended at Cactus and 91st. Ave.

[raydog]

Vman, can I just purge out 4, flush a little with 5.1, then install 5.1 without the horrific results discussed above? Is "the attack of the rubber eating liquid" just referring to DOT 5? Thanks, Raydog

[DropBusa]

[B]WHY?[B]
Switching to DOT 5 is not necessarily an improvement.

Yes, DOT 5 will not typically harm paint, plastics, etc. True also, that it won't absorb moisture. Yes, it will last longer in your brake system. Yes, it has a good boiling/freezing differential. There's a couple of other benefits, I'm sure.

But wait a minute! DOT 5 is silicone based, and therein lies a little flaw. Silicone defies the laws of physics (well, at least it bends them a little). Liquids do not compress, as you probably already know. Silicone, however can emulate fluid compression, in that it a given volume of silicone can be made to occupy a smaller space. *

What does that have to do with your clutch, or brakes? Well, it's simple. Under hard braking, especially when your fluid has become hot, something awful can happen. Let's say that you panic brake, your brake pads, rotors, and fluid is hot. You squeeze the lever to the grip and...that's right, you don't stop. Why? The silicone based DOT 5 has compressed, and you could not supply enough fluid past the piston to push the caliper pucks against the pads to squeeze the rotors with enough force to effect a stop. To get out of that situation, you would have needed a force-multiplier, or a master cylinder with a re-sized bore.

DOT 4 is uses glycol. Glycol can ruin plastic, paint, certain types of rubber. DOT 4 also should be replaced in your clutch, or brake system every two years, as it will absorb water, and that ruins hydraulic systems. But, DOT 4 behaves according to the laws of physics. That's a real plus for us bike enthusiasts. What DOT 4 will do, is give you a very good feel for your brakes. Since it does not compress, it is predictable. Your brake feel will be positive at the lever. As we have only two wheels on the road, positive feedback from our brakes (or hydraulic clutches) is imperative.

If you want to REALLY make an improvement, I would suggest braided lines, and a combination of pads and rotors that "hook" better than stock. If you want to really go nuts, radial master cylinders, and some high-end calipers, such as Brembo. What fluid would I recommend...personally, I'd stick with the DOT 4.

Have a look at what lots of other manufacturers, both car and motorcycle, are using. Even Harley-Davidson finally stepped up and uses DOT 4 (Brembo calipers too). You'll find the majority of brake systems out there use DOT 4.

If you do decide to go forward and switch to DOT 5, I would suggest changing ALL the rubber (Buna-N, Nitrile, etc.) in your brake/clutch system, as well. The longer your rubber parts have been exposed to DOT 4, the less likely they will be to happily accept DOT 5. Your o-rings, seals, etc. can become swollen by the addition of DOT 5, or even become soft, and disintegrate. I would STRONGLY suggest that you do a full rubber swap if you do the switch, as a brake failure, or leaks are a real bummer.

+1 There's a reason why it says Dot4 only. Sometimes the R and D guys know more than you.

nahh thems r&d guys dont know what they talkin bout,really though seems like there are alot of people who know better than the factory.

If all the "regulars" know more than the R&D guys, why are you not writing the standards?

[DropBusa]

I don't know about any of you guys but I have had my rear tire 3 feet in the air stopping quickly. *The rear in the air was unintentional. *Scared the crap outta me. *This was done with all stock brakes. *How can it possibly stop faster if the rear end will go skyward already?

Again id tend to agree. If stoppies can be performed on such a large bike with stock brakes; why bother with anything else. Unless of coarse you want to just be unique. Which to that i say "always remember, you are unique, just like everyone else!"

[raydog]

Vman, can I just purge out 4, flush a little with 5.1, then install 5.1 without the horrific results discussed above? Is "the attack of the rubber eating liquid" just referring to DOT 5? Thanks, Raydog

[vman1300]

Vman, can I just purge out 4, flush a little with 5.1, then install 5.1 without the horrific results discussed above? Is "the attack of the rubber eating liquid" just referring to DOT 5? Thanks, Raydog

Yes, DOT 5.1 is compatible with DOT 3 or 4. I use the Motul brand and we do keep a few cases in stock. I am going off memory here...the boiling point is 20 or so degrees higher.

Brake fluid is often overlooked. I change mine after every trackday or Gap event. Cheap insurance for the most braking.

Let me know if I can help.

[roadthing]

Vman, can I just purge out 4, flush a little with 5.1, then install 5.1 without the horrific results discussed above? Is "the attack of the rubber eating liquid" just referring to DOT 5? * *Thanks, Raydog

Yes, DOT 5.1 is compatible with DOT 3 or 4. I use the Motul brand and we do keep a few cases in stock. I am going off memory here...the boiling point is 20 or so degrees higher.

Brake fluid is often overlooked. I change mine after every trackday or Gap event. Cheap insurance for the most braking.

Let me know if I can help.

Okay, kids. Here's a very informative, and helpful link on brake fluids.

Again, if you are going to switch, I REALLY STRESS replacing all seals, gaskets, etc. I would personally not risk a brake failure. I don't want another 'Busa rider (or rider in general) to take any unnecessary risks with their brakes.
A Ducatisti's take on brake fluids

[raydog]

Thanks Vman, I'll get back to you......and to those of you commenting on your satisfaction with OEM Busa brake systems, It's not just how your brakes function "once". That is only a small part in the description of "effective brakes". For some, stock brakes will be fine, for others, about 20 minutes of twisties or track riding will demonstrate the inadequate performance of stock units. 90 degree+ weather, multiple intense stops without adequate cool down time and many other factors require aftermarket brake components to reduce performance deterioration. I'm not trying to sound like a "know it all" but if you've ever felt real brake fade in a demanding situation, the first improvement you'd make to your bike would be lines, pads and fluids! Raydog