Best DOT 5.1 Brake Fluid for Bicycle Disc Brakes (Why We Recommend Liqui Moly)
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Choosing the right brake fluid keeps your hydraulic brakes powerful, consistent, and easy to service. If your brakes use DOT fluid (not mineral oil), our recommendation is Liqui Moly DOT 5.1 for its high boiling point, low viscosity, and proven reliability.
Who Uses DOT Brake Fluid?
Most bicycle brakes use either DOT fluid or mineral oil. DOT brands include:
- SRAM / Avid – most models use DOT 5.1 (note: SRAM DB8 uses mineral oil)
- Hope – DOT
- Hayes – DOT
- Formula – DOT (except Cura models, which use mineral oil)
- Older Magura models – some early brakes used DOT; modern Magura brakes use mineral oil
Mineral oil brands: Shimano, TRP/Tektro, modern Magura, Campagnolo (do not use DOT in these systems).
DOT 5 vs DOT 5.1 (Quick Guide)
- DOT 5: silicone-based, not used in bicycle brakes and not compatible with DOT 3/4/5.1 systems.
- DOT 5.1: glycol-based, compatible with DOT 3/4 systems; higher boiling point and lower viscosity than DOT 4.
Why We Recommend Liqui Moly DOT 5.1
- High dry boiling point (~270 °C) – resists fade on long descents.
- Low viscosity – fast lever response and smoother bleeding, even in cold weather.
- DOT-certified – compatible with any bicycle brake that specifies DOT 3/4/5.1.
- Great value & availability – premium automotive-grade fluid in a handy 250 ml bottle.
Service Tip: How Often to Change DOT Fluid
DOT fluid is hygroscopic (absorbs moisture). For consistent performance, bleed and replace about every 12 months, or every 3– 6 months for heavy E-Bike MTB/Downhill use or humid climates.
FAQs
Can I mix DOT 4 and DOT 5.1?
Yes, they’re compatible (both glycol-based). Performance will match the lower grade, so a full flush is best.
Is DOT 5 the same as DOT 5.1?
No. DOT 5 is silicone-based and incompatible with DOT 3/4/5.1 systems.
Can I use DOT in Shimano or TRP brakes?
No. Shimano, TRP/Tektro, and modern Magura use mineral oil only. Using DOT will damage seals.
Does lower viscosity help bleeding?
Often yes. Lower-viscosity DOT 5.1 flows more easily through small passages, helping air escape during a bleed.