Dot 4 Brake Fluid Question

Bedifferent

Old man on a bike
Joined
Dec 11, 2014
Messages
1,764
Location
Coldwater, MI
Ride
2015 Rocket 3 Touring
Okay everyone, I have a question looking for a definitive answer.

I have been reading through some new and old posts on the importance of changing out brake fluid every couple of years. Many of the posts are way out of date. Somewhere I read not to use Synthetic Dot 4 just a standard high quality Dot 4. The manual I downloaded off the forum specifies Dot 4, but the manual is from 2007 as I recall.

I have a 2013 non ABS touring I want to swap the brake fluid out on, but working from a manual dated 2007 has to leave me asking the question...Have the Dot 4 specifications changed for the newer bikes? If you have a new manual and if you look in the General Specifications section for "Brakes" does it still just say Dot 4?

Things haven't change much on the Rocket over the years from what I can see, but there have been some changes in fluid recommendations. Before I go out and buy brake fluid to swap out, I would like to confirm "FOR SURE" what the current brake fluid specifications are. Thanks

By the way, a pretty good article on brake fluids....Be sure you read the whole article as it is 5 pages long. Excellent information!!

Tech Article: Brake Fluid
 
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My manual says dot 4 brake fluid .Got the manual when I bought my R3T.

Thanks....Sounds like a definitive answer to me. Reading the article gave me a lot of good insight into the whole brake fluid thing. Sounds like a straight Glycol based fluid. Not good to mix with other silicone based, but apparently you can do a full exchange if you work at it. Not going to do that. Change your fluid out on a low humidity/dry day. Apparently, it's all about trace amounts of moisture that develop in the fluid over time which dramatically lowers the boiling point and also leads to corrosion. No way around it...swap out the fluid every two years.
 
As an update or afterthought to my post, it should be noted that "ALL" brake fluids are "synthetic" in nature and not petroleum based. "Synthetic" should not be the defeating word in choosing a Dot 4 brake fluid if you see that on the container. The more important word to stay away from is "Silicone or Siliconized" as found in Dot 5. Any high quality Dot 4 brake fluid for motorcycles which states it that it mixes with other Dot 3 or 4 fluids should be an exceptable choice. This becomes even less important if you are making a good effort at exchanging out all of the fluid as much as possible.
 
As an update or afterthought to my post, it should be noted that "ALL" brake fluids are "synthetic" in nature and not petroleum based. "Synthetic" should not be the defeating word in choosing a Dot 4 brake fluid if you see that on the container. The more important word to stay away from is "Silicone or Siliconized" as found in Dot 5. Any high quality Dot 4 brake fluid for motorcycles which states it that it mixes with other Dot 3 or 4 fluids should be an exceptable choice. This becomes even less important if you are making a good effort at exchanging out all of the fluid as much as possible.
good advice there,,never overlook brake maintenance
I bought a 2013 roadster some time ago. and since I decided to refresh everything I will have a baseline to figure out the maintenance .started with two bottles of DOT4 brake fluid I do not fancy brake problems on the road so I flush out all the fluids from the master cylinders , the line and the brakes and pumped new fluid cheap insurance if you ask also installed speed bleeders ($18.00) so you can pump the pedal or lever without bothering to close the nipple. a steel ball mounted on a coiled spring inside the nipple close the line when it overpowers the fluid pressure very practical ! so new oil and filter , new fluids, new tires, moved the ignition barrel to mid level leftside , turfed out the ridiculous vespa horn and installed a dual trumpet horn with the compressor where the original horn was, also turfed out the air filtration and placed a ramair system. on the other side a jardine replace the factory muffler, replaced the suspension with wilbers shocks front and back and while working the front replaced the handlebar, next week some electric work light bypass , PC-8 install ,more powerfull light in the red lens in the back( I hate to do that electric stuff). this spring cam, pistons, and cam tensionner all from N,L. got the tools and parts already
my oh!! my this spring I will enjoy riding this beast to Nels shop in woodinville for the best tuning possible expecting some awesome figures ... there ! ...that is my winter project oops I forgot to mention mittzy awesome quick release brackets he sent me last year they are now mounted on the new ride
 
good advice there,,never overlook brake maintenance
I bought a 2013 roadster some time ago. and since I decided to refresh everything I will have a baseline to figure out the maintenance .started with two bottles of DOT4 brake fluid I do not fancy brake problems on the road so I flush out all the fluids from the master cylinders , the line and the brakes and pumped new fluid cheap insurance if you ask also installed speed bleeders ($18.00) so you can pump the pedal or lever without bothering to close the nipple. a steel ball mounted on a coiled spring inside the nipple close the line when it overpowers the fluid pressure very practical ! so new oil and filter , new fluids, new tires, moved the ignition barrel to mid level leftside , turfed out the ridiculous vespa horn and installed a dual trumpet horn with the compressor where the original horn was, also turfed out the air filtration and placed a ramair system. on the other side a jardine replace the factory muffler, replaced the suspension with wilbers shocks front and back and while working the front replaced the handlebar, next week some electric work light bypass , PC-8 install ,more powerfull light in the red lens in the back( I hate to do that electric stuff). this spring cam, pistons, and cam tensionner all from N,L. got the tools and parts already
my oh!! my this spring I will enjoy riding this beast to Nels shop in woodinville for the best tuning possible expecting some awesome figures ... there ! ...that is my winter project oops I forgot to mention mittzy awesome quick release brackets he sent me last year they are now mounted on the new ride

I hesitate to say it, but you and I think a lot alike. I am a firm believer in heading everything off before I have a problem. Reading the forum has set me to checking and making an effort to correct every problem I have read about before it happens. I am amazed at how many horror stories I have read here and thought...what were you thinking, why didn't you check that. Some of the guys I ride with never check their bikes over and I've seen at least 3 of them crap out along the side of the road because of it. Inspecting your bike routinely is the key to not sitting along the road somewhere. It ain't like reading a Harley where you can find a dealer within 30 mile of anywhere. It still can happen, but.....Carrying a few extra spare part like a couple relays, an extra throttle grip, fuses, a simple compact multimeter, EB relays for the headlight to take the strain of the ignition, taking care of your battery and replacing it on a regular basis, cleaning battery connections top and bottom, tires, brakes, changing oil, bevel box oil, lube splines, air filter, replacing bulbs periodically, heck... I even carry the manual and wiring diagram on my cell phone plus a list of problems and fixes people have posted on the forum....the list goes on and on. This next spring I'll be checking those vacuum hoses and coil connections as well.

It looks like your going to be busy way above routine maintenance. You have your work cut out for you, but it sounds like fun. By the way, I was actually looking at some speed bleeders earlier today. Stay ahead of the game I say and take a little peace of mind in the fact that you've done your best to keep the wheels rolling.
 
I just changed out my brake fluid for the first time today after owning the bike nearly 11 years. The fluid was brown and pretty nasty looking. Brake performance is much better now. Certainly not going to wait that long again to flush the brake lines, 2 years max. And definitely will be getting a speed bleeder for the next time I do this, what a pita to do it without One.
 
I just changed out my brake fluid for the first time today after owning the bike nearly 11 years. The fluid was brown and pretty nasty looking. Brake performance is much better now. Certainly not going to wait that long again to flush the brake lines, 2 years max. And definitely will be getting a speed bleeder for the next time I do this, what a pita to do it without One.


change your oil and filters as well and check your brake pads also leave nothing that can bite your ass later on
 
change your oil and filters as well and check your brake pads also leave nothing that can bite your ass later on

Oil, filters, & Brake Pads have been part of regular maintenance. The bike has 101000 miles on it. Brake fluid is just something I had not given much thought to, but certainly will from now on.
 
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