I recently passed 30k on my R and will be changing all fluids and getting the important valve adjustment. While changing the brake fluid, might as well upgrade to DOT 5.1 so my question is where would I be able to buy some DOT 5.1 brake fluid?

 

http://www.cobaltfriction.com

speak to rusty or andie

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nightrider &raquo;</TD></TR><TR><TD CLASS="quote">I recently passed 30k on my R and will be changing all fluids and getting the important valve adjustment. While changing the brake fluid, might as well upgrade to DOT 5.1 so my question is where would I be able to buy some DOT 5.1 brake fluid?</TD></TR></TABLE>

My suggestion is to stick with DOT 4 as DOT 5.1 would not be compatible with the other fluid (silicone vs non-silicone based). In addition, Motul 600 DOT 4 for example, actually exceeds the performance of the DOT 5.1 fluid. So there's really no reason to "upgrade" to 5.1 and have the compatibilty issues.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Wai &raquo;</TD></TR><TR><TD CLASS="quote">

My suggestion is to stick with DOT 4 as DOT 5.1 would not be compatible with the other fluid (silicone vs non-silicone based). In addition, Motul 600 DOT 4 for example, actually exceeds the performance of the DOT 5.1 fluid. So there's really no reason to "upgrade" to 5.1 and have the compatibilty issues.</TD></TR></TABLE>

i've read about this before about how silicone v. non-silicone based brake fluid is not compatible. DOT 5 is the one that is not compatible, but DOT 5.1 is. it was a few months ago that i read about it here on HT. i'm actually thinking about just using DOT 4 though because it's somewhat of a hassle for me to get DOT 5.1.

 

the dot number is how they perform when contaminated with a certain percentage of water.

so a better performing fluid could have a lower dot number.

keep your fluid clean, never keep open bottles for very long(or at all), and flush and bleed frequently!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Wai &raquo;</TD></TR><TR><TD CLASS="quote">My suggestion is to stick with DOT 4 as DOT 5.1 would not be compatible with the other fluid (silicone vs non-silicone based).</TD></TR></TABLE>

DOT 5 is silicone-based brake fluid. DOT 5.1 isn't, and DOT 5.1 is compatible with DOT 3 and DOT 4.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Wai &raquo;</TD></TR><TR><TD CLASS="quote">In addition, Motul 600 DOT 4 for example, actually exceeds the performance of the DOT 5.1 fluid.</TD></TR></TABLE>

Motul's boiling points are indeed higher than the DOT 5/5.1 requirements. Here are the dry and wet boiling points for many of the most popular brake fluids:

ARRANGED BY DRY BOILING POINT:

DRY:401F -- WET:284F --- DOT3 MINIMUM
DRY:446F -- WET:311F --- DOT4 MINIMUM
DRY:500F -- WET:356F --- DOT5 MINIMUM
DRY:502F -- WET:343F --- VALVOLINE SYNPOWER
DRY:509F -- WET:365F --- MOTUL 5.1
DRY:527F -- WET:302F --- AP RACING 551
DRY:536F -- WET:392F --- ATE SUPERBLUE/TYP200
DRY:590F -- WET:410F --- AP RACING 600
DRY:590F -- WET:518F --- CASTROL SRF
DRY:593F -- WET:420F --- MOTUL RBF600
DRY:610F -- WET:421F --- NEO-SYNTHETIC SUPER DOT 610
DRY:620F -- WET:425F --- COBALT SUPER XRF

ARRANGED BY WET BOILING POINT:

DRY:401F -- WET:284F --- DOT3 MINIMUM
DRY:527F -- WET:302F --- AP RACING 551
DRY:446F -- WET:311F --- DOT4 MINIMUM
DRY:502F -- WET:343F --- VALVOLINE SYNPOWER
DRY:500F -- WET:356F --- DOT5 MINIMUM
DRY:509F -- WET:365F --- MOTUL 5.1
DRY:536F -- WET:392F --- ATE SUPERBLUE/TYP200
DRY:590F -- WET:410F --- AP RACING 600
DRY:593F -- WET:420F --- MOTUL RBF600
DRY:610F -- WET:421F --- NEO-SYNTHETIC SUPER DOT 610
DRY:620F -- WET:425F --- COBALT SUPER XRF
DRY:590F -- WET:518F --- CASTROL SRF

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BlueR &raquo;</TD></TR><TR><TD CLASS="quote">http://www.cobaltfriction.com

speak to rusty or andie </TD></TR></TABLE>

Yup. You can buy many of the fluids listed above from Cobalt.