clutch and brake fluid flushes: worth it?
Road Master
Joined: Dec 2016
Posts: 981
Likes: 182
From: Fairfax County, VA
it's also more compressible (more so as temps rise due to air solubility in silicon - micro bubbles impossible to remove), moisture will remain localized because it is not absorbed - water will settle out = bad - corrosion, vapor lock), therefore not good for ABS. Also lower viscosity (may or may not be bad depending on your cold weather riding habits). My advice, stay away from it.
Seasoned HDF Member
Joined: Apr 2009
Posts: 44,807
Likes: 29,747
From: PNW
I've got 30k on my 3 year old bike and I'm taking it to the dealer for a flush. Better to be safe than sorry and it's recommended at 2 years for a reason.
As far as it works okay and the bike is being sold - I would feel better about selling my bike as well maintained and up to date on service. Your buyer will feel better knowing you stayed on top of things and you'll feel better knowing you sent him off on a safe ride.
As far as it works okay and the bike is being sold - I would feel better about selling my bike as well maintained and up to date on service. Your buyer will feel better knowing you stayed on top of things and you'll feel better knowing you sent him off on a safe ride.
Seasoned HDF Member
Joined: Apr 2015
Posts: 6,863
Likes: 3,727
From: St. Charles, MO
By the time your brake fluid starts to show color, it may be too late.
Once upon a time, I bought a used bike that was 12 years old. Brake fluid in the window looked just fine, brakes worked just fine. Shortly after purchase, I saw a little bit of a cloud in the bottom of the window; it was kind of reddish. When I flushed the brakes, the fluid was fine until near the end, then it was rust-colored. I pulled the master cylinder off and broke it down - the corrosion and scoring in the tube was significant!
I replaced the entire master cylinder with a spanky new one and lo and behold, the brakes far better than they did before. Looking at that scoring, I replaced the rear MC just for good measure.
I flush my brakes regularly now.
Once upon a time, I bought a used bike that was 12 years old. Brake fluid in the window looked just fine, brakes worked just fine. Shortly after purchase, I saw a little bit of a cloud in the bottom of the window; it was kind of reddish. When I flushed the brakes, the fluid was fine until near the end, then it was rust-colored. I pulled the master cylinder off and broke it down - the corrosion and scoring in the tube was significant!
I replaced the entire master cylinder with a spanky new one and lo and behold, the brakes far better than they did before. Looking at that scoring, I replaced the rear MC just for good measure.
I flush my brakes regularly now.
Grand HDF Member
Joined: May 2008
Posts: 4,585
Likes: 673
From: Rolla
Not to hijack the thread, but what about going to DOT 5? Its a better synthetic fluid, less costic (wont eat paint like DOT 4) and seems to hold up better under friction and heat.
I was considering going to DOT 5 when I chrome out the controls, change over to braided lines and chrome calipers. I know the clutch slave would need to be rebuilt with new rubbers, but if I start the new masters, lines and calipers with DOT 5, it should all be good. Is there an issue with going to DOT 5 with ABS?
I was considering going to DOT 5 when I chrome out the controls, change over to braided lines and chrome calipers. I know the clutch slave would need to be rebuilt with new rubbers, but if I start the new masters, lines and calipers with DOT 5, it should all be good. Is there an issue with going to DOT 5 with ABS?
https://en.wikipedia.org/wiki/DOT_5
DOT 5 brake fluid is not compatible with anti-lock brake systems.
Road Master
Joined: Dec 2016
Posts: 981
Likes: 182
From: Fairfax County, VA
Stellar HDF Member
Joined: Aug 2006
Posts: 2,151
Likes: 406
From: Hurdle Mills NC
No question. Yes.
You really cant see it on the Harley reservoirs .. but very clear windows into these on other manufacturers bikes.
The color will tell the story. When the oil is old and spent it will look like coffee. Actually if its this dark its way over due. I have mine done by my Indy every 20k.
You really cant see it on the Harley reservoirs .. but very clear windows into these on other manufacturers bikes.
The color will tell the story. When the oil is old and spent it will look like coffee. Actually if its this dark its way over due. I have mine done by my Indy every 20k.
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Seasoned HDF Member
Joined: Apr 2015
Posts: 6,863
Likes: 3,727
From: St. Charles, MO
Oh! Sorry, my bad... No, it was actually DOT3. The bike was an early 80's jap bike.
