Where to get larger quantitities of Dot 5.1 cheap and is there much difference in quality

[nathanm]

Why/how do you go through so much brake fluid ?

Tinkering with older bikes and older brakes probably.

I always thought Hayes 9 were the pinnacle for modern hydraulic braking systems and run them on all my bikes.

But in honesty, I do tinker with plenty of avid/sram brakes do a bunch of servicing for people as well as help out at the local bike collective and give away plenty of fluid. Once ive cracked a bottle I like to use it quickly. I reckon most of us current or ex race/rally guys know the importance of braking systems and use the highest quality stuff we can put into our mechanical toys, or at least should be.

Personally I actually hate the stuff, gimme Shimano Mineral Oil everyday of the week.

 

[Calvin27]

I always thought Hayes 9 were the pinnacle for modern hydraulic braking systems

Allow me to introduce to you: https://www.bike24.com/p2610756.html

Personally I actually hate the stuff, gimme Shimano Mineral Oil everyday of the week.

See above!

 

[pink poodle]

Sounds like @nathanm is taking about an aspiring career in amateur film!

I give away plenty of fluid

 

[ausdb]

One of the old photography home development tricks for air sensitive fluids is to drop marbles in your container as you use it to get the fluid level back to the top, squeeze the container to get the fluid to the very brim and put the lid back on.

Or what about one of the old concertina bottles that you could get as well.

 

[nzhumpy]

tackling black runs as a rookie in queenstown on a hire bike.

 

[cokeonspecialtwodollars]

My fastest recorded top speed on a bicycle is 93.6km/h, this and my top five fastest speeds were all on "the bike with the skinny tyres that shall not be named". The top descent in question was 14.55km and dropped 820vm and I had no issues with brake fade. My "that's why he wore the brown pants" moment was a 67.7km/h top speed descent on the fat bike with probably 12kg of bike packing gear strapped on, it was 11km and 67vm. Brakes on that bike have now been upgraded to DH spec.

 

[Flow-Rider]

My fastest recorded top speed on a bicycle is 93.6km/h, this and my top five fastest speeds were all on "the bike with the skinny tyres that shall not be named". The top descent in question was 14.55km and dropped 820vm and I had no issues with brake fade. My "that's why he wore the brown pants" moment was a 67.7km/h top speed descent on the fat bike with probably 12kg of bike packing gear strapped on, it was 11km and 67vm. Brakes on that bike have now been upgraded to DH spec.

Is that you Coke?

 

[cokeonspecialtwodollars]

Is that you Coke?

View attachment 397680

On 'yer right

 

[pink poodle]

Is that a Kevin Arnold seat?

 

[Flow-Rider]

Is that a Kevin Arnold seat?

I'm not sure what is, looks like they modified the lower chain stay.

 

[pink poodle]

Pretty sure that is Kevin Arnold racing to Winnie's place.

 

[slowmick]

Can/should you mix Dot 5.1 fluids?

I bought a cheap set of Hayes Dominions early in the year that I plan to install after Christmas. I assume they have Hayes fluid in them. Should I get more Hayes fluid to bleed them or get a bottle of Castrol and either use that for the bleed or use it to push the Hayes fluid out and fill the system with Castrol? These are a first non Shimano brakes I have played with. Having never used two syringes to bleed before I see a confession in the new year.

 

[ozzybmx]

Can/should you mix Dot 5.1 fluids?

I bought a cheap set of Hayes Dominions early in the year that I plan to install after Christmas. I assume they have Hayes fluid in them. Should I get more Hayes fluid to bleed them or get a bottle of Castrol and either use that for the bleed or use it to push the Hayes fluid out and fill the system with Castrol? These are a first non Shimano brakes I have played with. Having never used two syringes to bleed before I see a confession in the new year.

Yes, done it loads of times. Even poured the last of a bottle of green Dot 5.1 into a partly used bottle of red Dot 5.1.

Have used numerous different brands over the years.

 

[oldcorollas]

can mix 5.1 with 3 and 4 (all glycol based), but not with 5 (silicone based)...

main difference is in the boiling points, but moisture absorption (old fluid) will bring numbers down a fair bit.. how hot do those calipers actually get?

better to flush fully to have fresh fluid, rather than mix new fluid with old watery fluid...

 

[jrewing]

touche


You haven't seen 130kgs of me trying to go down Maydena dragging the brakes from top to bottom.

Pads will overheat before fluid i reckon

 

[The Duckmeister]

Can/should you mix Dot 5.1 fluids?

I bought a cheap set of Hayes Dominions early in the year that I plan to install after Christmas. I assume they have Hayes fluid in them. Should I get more Hayes fluid to bleed them or get a bottle of Castrol and either use that for the bleed or use it to push the Hayes fluid out and fill the system with Castrol? These are a first non Shimano brakes I have played with. Having never used two syringes to bleed before I see a confession in the new year.

DOT gradings are automotive industry based and not specifically bike industry. As noted in a previous post, DOT 3, 4 and 5.1 are variations of the same polyglycol base and can be mixed/substituted. Higher DOT rating brings higher boiling point of the fluid, but also an increasngly voracious appetite for water absorption, so the stuff needs to be replaced more frequently. DOT 5 is a totally different chemical base and not compatible with DOT 3, 4 or 5.1.

 

[rockmoose]

Don't forget kiddies, dot 5.2 for Honda.

 

[shiny]

Can/should you mix Dot 5.1 fluids?

I bought a cheap set of Hayes Dominions early in the year that I plan to install after Christmas. I assume they have Hayes fluid in them. Should I get more Hayes fluid to bleed them or get a bottle of Castrol and either use that for the bleed or use it to push the Hayes fluid out and fill the system with Castrol? These are a first non Shimano brakes I have played with. Having never used two syringes to bleed before I see a confession in the new year.

Hayes relies on a crazy tight fitting of the bleed fitting into the caliper and lever. If you don’t have a Hayes kit when hooking it all up give an extra little nudge to ensure it is locked in or risk pulling air into the system. Why they didn’t rely on an o-ring like others and have a taper bore instead.

Also 20 litres of brake fluid here @nathanm but Dot 4

https://www.sparesbox.com.au/products/bendix-high-performance-brake-fluid-dot-4-20l-bbf4-20l?gad_source=1&gclid=EAIaIQobChMIoM6GzaaIgwMVO6NmAh3DrwPEEAQYASABEgLgy_D_BwE

 

[Flow-Rider]

Hayes relies on a crazy tight fitting of the bleed fitting into the caliper and lever. If you don’t have a Hayes kit when hooking it all up give an extra little nudge to ensure it is locked in or risk pulling air into the system. Why they didn’t rely on an o-ring like others and have a taper bore instead.

Also 20 litres of brake fluid here @nathanm but Dot 4

https://www.sparesbox.com.au/products/bendix-high-performance-brake-fluid-dot-4-20l-bbf4-20l?gad_source=1&gclid=EAIaIQobChMIoM6GzaaIgwMVO6NmAh3DrwPEEAQYASABEgLgy_D_BwE

The biggest mistake people make with taper fit is not lubing the threads and doing the fitting up and loosening it a few times before the final tightening. The automotive industry has used this system for years with no problems