are they all the same? is the one for cars the same as the one for bikes, and will a regular commuting bike guy like me notice the difference between the 3 and 4? my cbr125 recommends 3 or 4.
are all dot 3 and dot 4 brake fluids created equal?
- Thread starter wideiris
- Start date
Yeah I think all the brands are pretty similar. The same DOT3 or DOT4 brake fluid is used for cars or bikes. The main difference between DOT3 and 4 is the boiling point, DOT4 can handle more heat before braking performance (and the fluid itself) degrades. I don't think you'll notice the difference commuting. Having said that; DOT 4 is the better choice.
Car2Slo
Well-known member
More info from web;
Polyglycol Based DOT3 - Color - Amber | One of the most common finds on the market and have a specific for cars designed for the late 80s period. Although compatible with our CL7/9s should you cannot find the required selected grade, this is not the correct specification to be used from factory recommendation guidelines. DOT3 also absorbs moisture the quickest and has the lowest boiling point and should only strictly be for road use.
Polyglycol Based DOT4 - Color - Amber | The benchmark specifications by the majority of car manufacturers, this is also the specific grade to be used with Hondas/Acura cars regardless of models. DOT4 is designed to absorb moisture slower than DOT3 and has a higher boiling point. This is both suitable for road use and track work. While the OEM Honda DOT4 brake fluid is sufficient for weekend trackdays, meets etc. Using racing specific DOT4 refined brake fluids will increase higher temperature tolerance particularly under hard braking conditions.
Silicone Based DOT5 - Color - Purple | Least common and also the most different from both grades above. DOT5 are primarily designed for cars not equipped with ABS units (Unless otherwise manufacturer specific)and this should not be used unless you're absolutely sure of what you're doing. DOT5 does not absorb moisture and holds the highest boiling point. This brake fluid is not compatible with either categories above and should never be mixed due to it's chemical properties.
Polyglycol Based DOT3 - Color - Amber | One of the most common finds on the market and have a specific for cars designed for the late 80s period. Although compatible with our CL7/9s should you cannot find the required selected grade, this is not the correct specification to be used from factory recommendation guidelines. DOT3 also absorbs moisture the quickest and has the lowest boiling point and should only strictly be for road use.
Polyglycol Based DOT4 - Color - Amber | The benchmark specifications by the majority of car manufacturers, this is also the specific grade to be used with Hondas/Acura cars regardless of models. DOT4 is designed to absorb moisture slower than DOT3 and has a higher boiling point. This is both suitable for road use and track work. While the OEM Honda DOT4 brake fluid is sufficient for weekend trackdays, meets etc. Using racing specific DOT4 refined brake fluids will increase higher temperature tolerance particularly under hard braking conditions.
Silicone Based DOT5 - Color - Purple | Least common and also the most different from both grades above. DOT5 are primarily designed for cars not equipped with ABS units (Unless otherwise manufacturer specific)and this should not be used unless you're absolutely sure of what you're doing. DOT5 does not absorb moisture and holds the highest boiling point. This brake fluid is not compatible with either categories above and should never be mixed due to it's chemical properties.
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Just don't mix them. If you have DOT 3 in your bike, technically you can mix DOT 4 into it, but I still wouldn't do it. DOT 5 cannot be mixed into anything.
http://jimsgarage.wordpress.com/2007/01/09/dot-3-dot-4-and-dot-5/
http://jimsgarage.wordpress.com/2007/01/09/dot-3-dot-4-and-dot-5/
. The R6, I change it every couple of years.On a STREET bike, doesn't matter what it is, you would be very hard pressed to exceed the performance limits of the cheapest DOT3 brake fluid that you can find. There is just no way that you are going to get enough heat into the braking system for it to be an issue.
On a superbike in a roadracing application, it is likely a different story ... but on my 60 hp roadrace FZR400, I use brake fluid that I bought at Canadian Tire. Nothing fancy.
On a superbike in a roadracing application, it is likely a different story ... but on my 60 hp roadrace FZR400, I use brake fluid that I bought at Canadian Tire. Nothing fancy.
I cooked vstrom rear brake on stelvio pass following bus on the way down.
On a hot day with long enough hill going down you can cook brakes.
That is the reason why on some mountains they have brake test area
with nice runoff into the field if brakes fail.
No clue what fluid was in the system but once it overheated all pressure was lost
and it felt as if pedal was not attached to anything.
It just fell through...
Front was still good but I stopped until rear cooled off.
Idea of same thing happening to front too was scary...
On a hot day with long enough hill going down you can cook brakes.
That is the reason why on some mountains they have brake test area
with nice runoff into the field if brakes fail.
No clue what fluid was in the system but once it overheated all pressure was lost
and it felt as if pedal was not attached to anything.
It just fell through...
Front was still good but I stopped until rear cooled off.
Idea of same thing happening to front too was scary...
Why not just downshift and use engine braking? Even in the city I barely need to use the brakes on my 650R unless I'm riding quite aggressively. It will almost come to a stop just with engine braking. With a long hill coasting in a low gear should keep the speed down without wearing out your brakes. Same applies to manual cars/trucks (hence why you see signs on steep hill descents saying, "Trucks use low gear."
You are missing the very important DOT 5.1 option.
The 5.1 is also Polyglycol and is the better version after 4. Most racing applications will use 5.1 in their brake systems.
The DOT5 is NOT good for every day commuter cars and bikes because, even though it has a higher boiling point than DOT4, it will give you a spongey feel to your brakes. Silicone is highly compressible!
Have a read here: http://www.afcoracing.com/tech_pages/fluid.shtml
@ OP:
- You should be fine with DOT3
- You'll definitely be fine with DOT4
- Stay away from DOT5
- You'll most likely never take advantage of what DOT5.1 has to offer on a CBR125
This also applies to almost any 4-wheeled vehicle you may own as well.
Mostly it was used for trail breaking and you can not really ride at any speed smoothly behind the bus going through hairpins. One should definitely not ride down the mountain on the brakes but sometimes there is no choice.
I never experienced it before and at first I was thinking that I had leak and fluid was gone.
I never experienced it before and at first I was thinking that I had leak and fluid was gone.
Nothing personal, but this is a classic example of a very poor riding technique with a predictable consequence. Never in a million years should you cook a rear brake like that. In fact, the prospect of over heating a streetbike brake is ludicrous on a good day.
Whatever...
Once you are stuck at 9000ft behind a bus on 40 hairpins on the way down
with few hundred meters between them you might change your opinion.
You can NOT be in first or second gear and control speed like that, try to
get down the parking ramp for few levels with engine braking and you might get an idea.
Low gear is too twitchy for stop and go traffic on steep downhill grade.
I rode 4000km of those roads and it never happened again but not because I decided magically that engine is enough.
For the reference
https://maps.google.ca/maps?q=stelv...4oMQ7V6r4J9P8-rvLQ&cbp=12,359.16,,0,34.6&z=16
Once you are stuck at 9000ft behind a bus on 40 hairpins on the way down
with few hundred meters between them you might change your opinion.
You can NOT be in first or second gear and control speed like that, try to
get down the parking ramp for few levels with engine braking and you might get an idea.
Low gear is too twitchy for stop and go traffic on steep downhill grade.
I rode 4000km of those roads and it never happened again but not because I decided magically that engine is enough.
For the reference
https://maps.google.ca/maps?q=stelv...4oMQ7V6r4J9P8-rvLQ&cbp=12,359.16,,0,34.6&z=16
silverbullet132
Well-known member
Actually, I won't change my opinion. As I said, it's nothing personal, but for the benefit of the newer riders out there. Following distance, combination of using BOTH brakes and not depending on the rear, combining braking and coasting on engine braking would have solved your issue. How do you think the bus made it down without cooking its brakes? The part of this post that makes the least sense, is that motorcycle are by far the lightest vehicles on the road. Trucks, buses, etc have a far more legitimate case of brake fade due to their weight, and yet they manage to navigate these roads regularly.
Whatever again...
Here is how buses make it down. I got course info for you...
http://www.bctransit.com/sst/pdf/BCT-AirBrake-ppt.pdf
Apparently not all brake systems are equal... Imagine that...
Here is how buses make it down. I got course info for you...
http://www.bctransit.com/sst/pdf/BCT-AirBrake-ppt.pdf
Apparently not all brake systems are equal... Imagine that...
Whatever again, lol. Yes, I'm familiar with air brakes; teach the courses, been driving with them for 20 years, and I've been riding even longer. Never met a guy who cooks a rear brake though, so maybe the word is riders that are not equal, not brakes. Ride safe!
