Problems with clutch at high elevations.,,,
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Grand HDF Member
Joined: Mar 2007
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From: Deep in the heart of New Jersey
Problems with clutch at high elevations.,,,
Just spoke with a friend of mine who returned from Vegas. He said he ran up on a guy with a '18 ultra, who was having clutch operation problems. He said he called a local dealer who told him, if the clutch fluid hasn't been changed at the 2 year interval, that you could have problems in higher elevations. Has anyone head that, or had that problem in higher elevations? Like up in Colorado and such.,,
Outstanding HDF Member
Joined: Aug 2009
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From: Puyallup Wa.
Interesting.... Even more interesting after I Googled did a little reading I can't speak on it from experience. I don't know anything other than what I Googled. However makes me want to be more proactive with my brakes and clutch. I am definitely on that 2-year Edge.
Stellar HDF Member
Joined: Sep 2020
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From: Southeast
My brother had a huge problem with his clutch going up Pike's Peak. Like, no clutch. Once he came back down, everything was fine. We thought it was the weirdest thing. He has a '17 Ultra I believe. FYI.
Stellar HDF Member
Joined: Aug 2020
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From: College Station, TX
Yep, high moisture content (3%+) in the brake (clutch) fluid will cause the fluid to boil at high temps, or at lower temps at higher altitudes since the air is thinner. Much like how water will boil at room temperature under a vacuum. When the fluid boils, the oxygen in the moisture separates from the hydrogen (H2O). Gases (oxygen) compress causing the clutch to not function.
The same could happen with the brake fluid too. So it should be flushed every 2 yeardm or anytime the moisture content is 3% or above. And use a good quality DOT 4 brake fluid when flushing.
Paul
The same could happen with the brake fluid too. So it should be flushed every 2 yeardm or anytime the moisture content is 3% or above. And use a good quality DOT 4 brake fluid when flushing.
Paul
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From: Ft. Wayne IN
I have had my 2018 FLHCS Heritage brake fluid changed twice and certainly believe the moisture problems with DOT4 brake/clutch fluid. My question is WHY USE DOT 4? I have ABS brakes in all 3 of my cars and they use DOT3 brake fluid. DOT3 is way less hydroscopic than DOT4. I also know that DOT4 has a higher boiling point than DOT3, but do most of us really need this?
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Stellar HDF Member
Joined: Aug 2020
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From: College Station, TX
I have had my 2018 FLHCS Heritage brake fluid changed twice and certainly believe the moisture problems with DOT4 brake/clutch fluid. My question is WHY USE DOT 4? I have ABS brakes in all 3 of my cars and they use DOT3 brake fluid. DOT3 is way less hydroscopic than DOT4. I also know that DOT4 has a higher boiling point than DOT3, but do most of us really need this?
DOT 5 silicone brake fluid does not absorb moisture, but it is not compatible with brake systems with ABS. So it would seem that DOT 4 is the best choice, even if it does require more maintenance.
My guess is that your three cars with ABS may not be the latest models because all of the ones I'm familiar with use DOT 4. Although it does appear that Japaneses auto manufacturers do use DOT 3 with ABS. There is DOT 5.1, which is low viscosity and compatible with ABS. But I haven't see it in use from OEM manufacturers.
Paul
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From: Whiskey Falls, Texas
Yep, high moisture content (3%+) in the brake (clutch) fluid will cause the fluid to boil at high temps, or at lower temps at higher altitudes since the air is thinner. Much like how water will boil at room temperature under a vacuum. When the fluid boils, the oxygen in the moisture separates from the hydrogen (H2O). Gases (oxygen) compress causing the clutch to not function.
The same could happen with the brake fluid too. So it should be flushed every 2 yeardm or anytime the moisture content is 3% or above. And use a good quality DOT 4 brake fluid when flushing.
Paul
The same could happen with the brake fluid too. So it should be flushed every 2 yeardm or anytime the moisture content is 3% or above. And use a good quality DOT 4 brake fluid when flushing.
Paul
My Ultra Limited only had 2000 miles on it when I bought it. Several months later it has 12,000 miles on it and I'm riding in the mountains of Colorado, Wyoming and Montana on a road trip. Sure enough clutch starts going out.
When we stopped for the night in Cheyenne Wyoming, I let the bike cool then rode it to a Napa Auto Parts and bought a $49 vacuum bleeder for brakes, and sucked the fluid out and replaced it with new DOT 4. Clutch was like brand new again.
