Brake fluid change and the preferred brake fluid type

Du siehst das Forum als Gast - als registriertes Mitglied stehen dir alle Forenbereiche zur Verfügung. Wir freuen uns auf dich!

  • Hi.


    This is my first bike with ABS and I like to change brake fluid at least once per season, sometimes even more often.

    Tracer's manual says that after brake fluid change "HYDRAULIC UNIT OPERATION TEST" should be triggered using Yamaha Diagnostic Tool.

    Would this be the only difference in the brake fluid changing procedure compared to the bike without ABS?

    Does this test mix old brake fluid left in the ABS system with a new one, or there is some additional purpose of it? Maybe bleeding air from ABS system?

    In the case that one doesn't own Yamaha Diagnostic Tool, would it be enough to change the brake fluid and then just try triggering ABS couple of times during riding/


    What's about brake fluid type?

    Yamaha still specifies DOT 4, although DOT 5.1 should be superb in all the aspects:

    • higher dry boiling point
    • higher wet boiling point
    • compatible with DOT 4 braking systems (not aggressive to system parts)
    • can be mixed with DOT 4
    • much lower viscosity (should be important for ABS, for an example)

    I have used on my Freewind both DOT 4 and DOT 5.1 without any issue.

    Which is your preferred brake fluid for Tracer 700?

  • Just do the normal open-close procedure and everything will be fine. A couple of ABS activations and everything should be mixed just fine. There is no more air in the brake fluid in the ABS module than in the rest of the braking system. The share of the fluid in the ABS module is not that huge, so changing once a year and some ABS activations should be fine in terms of water and air content in the brake fluid overall.

    Using DOT 5.1 is fine, but there is no real benefit. The target should always be, to avoid reaching the boiling point. One step is to change the fluid more often than Yamaha specifies, so you don't go all the way down to the wet boiling point. But even with 2 year intervals and really cheap DOT 4, it is highly unlikely to get to the boiling point.

    Also, you are making the mistake of only checking the DOT requirements. A lot of DOT 4 brake fluid have higher boiling points than 5.1 specifies.

    Regarding ABS I'm not sure how relevant this is for the very crude ABS of the MT07 or Tracer. Might be worth a test to be honest. If it improves even a little bit, I would actually consider a change.

    Checking at the company where I got my latest DOT 4, I found this one:

    https://www.ravenol.de/produktgruppe/…venol-dot-4-lv/

    Even lower viscosity at -40°C than DOT 5.1, but DOT 4 specification.

  • Last season I rode with ATE DOT4 SL6 (lower viscosity)

    I've bought it by mistake in a store but decided to give it a try. At least it fullfills DOT 3 and 4 specifications.

    I changed the fluid as described above and forced the ABS to act by braking on sand/grass for some times with front and rear wheel.

    Some weeks later I had the chance to participate a security training. There was another MT-07 and we did emergency brakings side by side. The instructor said that my ABS works with slightly faster intervalls, but there was no big difference regarding the braking distance.

    This year I use standard DOT 4 by Motul. I don't care about the name of the brand, it's more important to change the fluid on a regular base, I assume.

  • Thx for the clarification!

    @johannes

    I've seen those Low Viscosity DOT 4 fluids. Sometimes they are refereed as DOT 4+ or SL6 (as Gonzo mentioned).

    Usually they cannot be marked as DOT 5.1 because of one of characteristics. In case of Ravienol you have linked, it's wet boiling point (172, should be above 180 for DOT 5.1 standard).

    Anyways, bottom line should be: any DOT 4 or better braking fluid and regular changes.

    How often should diaphragm in fluid reservoirs be changed?

  • Have u been exchanging brake fluid before?

    Tiefster Hochschwarzwald

    Specs:

    • Klasse A
    • 2019er MT07 Ice Fluo
    • Kurzes KZH
    • Lightech Lauflicht Blinker Hinten und Vorne
    • Gazzini Lenkerenden Spiegel
    • PUIG Windschild
    • V-Trec Kupplungs- und Bremshebel
    • Barracuda Sturzpads
    • GSG Moto Achspads
    • Rote Bremsflüssigkeitsbehälterabdeckung
    • Schwarze Bremsflüssigkeitsabdeckung
    • Wheelsticker
  • Have u been exchanging brake fluid before?

    Yes, Suzuki Freewind (streetified DR650) - many times. Refreshed front caliper and master cylinder once. Changed pads and rear disk.

    Then again, it's much less complex - it has just one disk in the front and no ABS.

  • Here you should start at the front caliper with the longest braking line distance to the master cylinder. Then the other front caliper, rear caliper at last. Thats what I've tought myself by reading repair manuals, somebody may correct me if I'm wrong.
    We have to improve our skills bike by bike with increasing complexity.


  • At the service manual you can find shematics of the two ABS working stages ( depressurizing phase / pressurizing phase). Theoretically I guess that brake fluid with air bubbles should flow through the ABS module and then back to the brake master cylinder without big effect to the braking process. If everything works like it is supposed to do (nothing clogged, no seized valves,...etc.)
    Thats why I would expect a spongy lever after an ABS braking, if there was air inside the ABS module behind the inlet solenoid valve before.

    A little bit of air inside the lines is not uncommon I think, so the system has to be able to handle this. <--- until here, my non-professional thoughts and expectations. Let's know as soon as you get deeper knowledge

    But the way you're asking tells me to give the default answer in this kind of cases: consult a dealership if something is suspicious (!) Blah blah, you know what I mean. Brakes, danger, death, accidents, suing ;)