Air bubbles in both brake reservoirs


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swr1977
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Air bubbles in both brake reservoirs

Post by swr1977 » Sun Mar 29, 2020 11:06 am



So two years ago I replaced the brake fluid in both brake reservoirs then bled the lines because of what looked like bubbles in the fluid. (cloudy fluid) Now it's spring time and I'm doing my normal checks, getting ready for riding season... I find again what looks like bubbles in both brake reservoirs.

Note: I live in Washington State and we get a lot of rain and it's very humid!

I wondering if instead of replace the DOT 3 fluid again and bleding the brakes yearly if I could use a synthetic? Has anyone ever put a synthetic brake fluid into their GL1000 and if it would solve this problem as a family member has suggested to me?


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Re: Air bubbles in both brake reservoirs

Post by WingAdmin » Sun Mar 29, 2020 7:06 pm

Cloudy fluid can be from moisture. There are lots of synthetic DOT3 brake fluids, but I think what you're asking is if you can use DOT5, which is non-hydroscopic (doesn't absorb moisture from the air). And the answer to that is an unqualified NO. DOT5 is silicone based, and can play havoc with the rubber seals in your bike. Also, if even the slightest bit of DOT3/4 fluid remains in your system when you try DOT5, it will cause problems.

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swr1977
Posts: 202
Joined: Sun Sep 29, 2013 9:18 am
Location: Puyallup, Washington, USA
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Re: Air bubbles in both brake reservoirs

Post by swr1977 » Sun Mar 29, 2020 8:55 pm

WingAdmin wrote:
Sun Mar 29, 2020 7:06 pm
Cloudy fluid can be from moisture. There are lots of synthetic DOT3 brake fluids, but I think what you're asking is if you can use DOT5, which is non-hydroscopic (doesn't absorb moisture from the air). And the answer to that is an unqualified NO. DOT5 is silicone based, and can play havoc with the rubber seals in your bike. Also, if even the slightest bit of DOT3/4 fluid remains in your system when you try DOT5, it will cause problems.
Ok thanks... I'll just replace the bad fluid with the regular DOT 3 I used last time... I'm just getting tired of having to drain, refill and bleed the lines ever year!
For Some there's THERAPY, for the Rest of Us There are MOTORCYCLES

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