G oog le BadWeB | Login/out | Topics | Search | Custodians | Register | Edit Profile


Buell Forum » XBoard » Buell XBoard Archives » Archive through March 08, 2010 » DOT3&4 brake fluid? « Previous Next »

Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

Greg_e
Posted on Wednesday, March 03, 2010 - 11:14 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Tried the search and again nothing but blank pages...

What are they thoughts on synthetic DOT3&4 rated brake fluid? I want to change the fluid in both ends and Valvoline 3&4 rated is on sale right now. Or should I just find regular DOT4 fluid and use the 3&4 in my car (which also needs a fluid change).
Top of pagePrevious messageNext messageBottom of page Link to this message

Ulynut
Posted on Thursday, March 04, 2010 - 06:08 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

You can't go wrong with following the manufacturers recommendations.
Top of pagePrevious messageNext messageBottom of page Link to this message

Kbaddict
Posted on Thursday, March 04, 2010 - 12:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

I changed my Xb to a firebolt top triple back about 10 months ago and I had to use a different master cylinder. I've been using the valvoline 3&4 rated this whole time without a problem.
Top of pagePrevious messageNext messageBottom of page Link to this message

Sloppy
Posted on Thursday, March 04, 2010 - 01:07 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

DOT 3/4 complies with both standards. It will be fine. No reason to purchase anything different.

I do NOT recommend DOT 3 in the front caliper if you enjoy being aggressive on the brakes - and that is spoken from experience!
Top of pagePrevious messageNext messageBottom of page Link to this message

Greg_e
Posted on Thursday, March 04, 2010 - 01:24 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

OK, since the Valvoline is on sale I'll probably go with it then. I was just concerned because the required rating is of course DOT4 and I had never used a mixed rating fluid like this before.

Also it has been said that mixing DOT3 and DOT4 fluid is very bad as they can break each other down and or each requires a different rubber compound in the seals (might be true, might not). Since it has DOT4 in it now, there would be some leftover in the lines after the drain so I would never consider DOT3 in a bike.
Top of pagePrevious messageNext messageBottom of page Link to this message

Sloppy
Posted on Thursday, March 04, 2010 - 02:11 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

It's okay to mix, but only as a forward compatability.

A DOT 3 system "should not" use a DOT 4 fluid.

But a DOT 4 system "can" use a DOT 3 fluid. And you "can" mix them in a DOT 4 system.

"Why" you ask? DOT 4's have an extra chemical in it (I forget what it is - it's been a few years since school) that allows for a higher "dry" boiling point temperatures. This extra chemical has not been tested on older, DOT 3, rubber systems so it "may" not be compatible with it. Likely it will be okay, but the manufacturer has never tested so they don't know.

So why even use a DOT 3 fluid over a DOT 4. DOT 3's "typically" hold their boiling point properties over a longer period of time than DOT 4's. In other words, DOT 3's don't need to be changed out as frequently as a DOT 4. DOT 4's should be changed at least every 2 years, depending upon where you ride. I ride year round so I change mine out annually.
Top of pagePrevious messageNext messageBottom of page Link to this message

Andymnelson
Posted on Thursday, March 04, 2010 - 02:14 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Typically 3 and 4 are roughly the same. The standard laid out is DOT rated need to have a dry boiling point of at least 401 degrees, and a wet boiling point of at least 284. DOT 4 is 446 and 311.

DOT 5 is the one you don't want to mix, as it is silicone based rather than glycol based.

So if it says 3 and 4...well that really just means it's 4! I believe that ALL DOT 4 brake fluids are also DOT3 compliant.

Just make sure you get one that says 4 and you'll be good to go.
Top of pagePrevious messageNext messageBottom of page Link to this message

Azxb9r
Posted on Thursday, March 04, 2010 - 04:13 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Typically 3 and 4 are roughly the same. The standard laid out is DOT rated need to have a dry boiling point of at least 401 degrees, and a wet boiling point of at least 284. DOT 4 is 446 and 311.

DOT 5 is the one you don't want to mix, as it is silicone based rather than glycol based.

So if it says 3 and 4...well that really just means it's 4! I believe that ALL DOT 4 brake fluids are also DOT3 compliant.
Top of pagePrevious messageNext messageBottom of page Link to this message

Blake
Posted on Thursday, March 04, 2010 - 05:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Then there's the outrageously confusing DOT5.1. Whoever thought that was a good designation ought to be tortured a bit.
Top of pagePrevious messageNext messageBottom of page Link to this message

Blake
Posted on Thursday, March 04, 2010 - 05:44 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Good google hit...

http://www.afcoracing.com/tech_pages/fluid.shtml
« Previous Next »

Add Your Message Here
Post:
Bold text Italics Underline Create a hyperlink Insert a clipart image

Username: Posting Information:
This is a private posting area. Only registered users and custodians may post messages here.
Password:
Options: Post as "Anonymous" (Valid reason required. Abusers will be exposed. If unsure, ask.)
Enable HTML code in message
Automatically activate URLs in message
Action:

Topics | Last Day | Tree View | Search | User List | Help/Instructions | Rules | Program Credits Administration