Brake fluid change

[piper51]

Hi Everyone,  Is it necessary to change the brake fluid and clutch fluid at 12000 miles? If I use synthetic brake fluid can I go longer? Is there an easy way to do the rear or do I have to bleed the rear and front at the same time? Thanks for your help.

[Valker]

It's time more than mileage. Every year or two for both ends.

[piper51]

why is that? Does the fluid break down?  So I need to invest in a brake bleeder?  If the fluid isn't discolored, how do I know when I have all the old fluid out without draining the reservoir completely?

[NITRO]

The fluid picks up water and, as such, isn't as effective.

You will very likely be able to tell the difference between the new and old fluid after two years. Try it and see what you think.

You can use a brake bleeder, a hose with a jar, or get some speed bleeders. Up to you.

[piper51]

Thanks for the help. Guess I better get busy and change the fluids. I saw the speed bleeders and they look like a good investment.  Happy Ridin!!

[Patrick]

I don't think fluid change is as necessary as some think even though I think it is necessary,just not as often.. Heat raises cane with fluids today and is the main reason for changing/replacing it.. I don't recommend synthetic brake fluids, I don't like them, but, do use new fresh fluid and don't leave the top off for any period.. The front and rear systems are separate so you don't have to do them together.. I don't use speedbleeders either, but, you can if you like.. I use the old fashion pump/squeeze, open, close, release, then do it again and again method..Its worked since the 1930s and still works just fine..

[piper51]

aren't the front and rear brakes tied together on one side?

[RP#62]

No totally separate.
-RP

[MP]

No.

MP

[PhredValk]

Integrated brakes started in the mid 80's on Goldwings, and Honda uses it on lots of bikes; but I find no evidence that they ever used it on the Valks. I can't find any brake hose running foreword from the rear master, so front and rear are independent systems.
Check Shoptalk to see if you start on the right or left on the front lines.
Fred.

[chrise2469]

why is that? Does the fluid break down?  So I need to invest in a brake bleeder?  If the fluid isn't discolored, how do I know when I have all the old fluid out without draining the reservoir completely?

A few things, brake fluid absorbs water, its what it does.  As it does it gets darker.  That's why there are sight glasses on the brake and master cylinder.

A mighty vac is a good investment and makes bleeding brakes very easy.

My preferred method to bleed the brakes and or clutch is to first suck all the old brake fluid from the reservoir and just leave a mm or so in.  Fill the brake reservoir back up with new fluid and then bleed the line.  The mighty vac is good for both parts of this.

I wouldn't change to synthetic, dot 4 is cheap and there is no need to repurge the lines.

The valks do not have a linked brake system, there are two lines to the front brakes from the master cylinder.  The rear master cylinder is located on the right side of the bike just above the brake and it hides under a small piece of chrome.

Hope this helps you.

[sandy]

Some of you are confusing synthetic with silicone. You CAN mix synthetic with conventional DOT4. Not silicone. I use a vacuum powered bleeder (uses compressed air through an eductor). Pull all the fluid out. Refill with alcohol and pull all that out. Refill with DOT4 (Valvoline synthetic) and bleed.

[Robert]

Sandy had it right Dot4 is the stuff I use Castrol GTLMA some fluids do say synthetic on them when they are dot 3 and dot 4 but the dot 5 stuff is usually silicon and not interchangeable with the dot3 and 4. Just to add to the confusion not all dot 5 are silicon either just for info. I wouldnt recomend pulling all the fluid out and letting air into the system as this causes you extra work and the results are really not any better. If you let air into the lines its harder to get out than just letting the fluid flush out the lines and sometimes its a pia to get all the air out. Take all the fluid out of the reservoir and refill with fresh fluid keep bleeding either by mighty vac or bleed screws or whatever till the fluid comes out clean of course refilling your reservoir as you go. Brake fluid is hygroscopic meaning it absorbs liquid this is done because there is always water in the brake system because of water in the air or condensation. So the fluid absorbs this water so it doesn't sit in the system and corrode the one spot it sits on possible causing failure. As this process is happening the fluid goes through changes these are darkening of fluid colors and lower boiling point. Boiling point is important because brakes create friction that creates heat so that heat is transferred to the fluid and it boils which causes air that in turn causes loss of brakes. Some never change their brake fluid from day a but some its done to spec and I haven't seen to many difficulties from those that are lax. But from the diligent their brakes are more responsive give a more positive feel and brake parts usually dont go bad.

[valkyriemc]

Cover any exposed surfaces with a towel(s) or an old blanket. I wrap cloths tight right around the resevoirs to help with drips etc.

[Ricky-D]

The sight glass are so you can easily check the fluid levels.

It's convenient to be able to see the fluid color but that is not the reason for the sight glass.

***

[Spirited-6]

The sight glass are so you can easily check the fluid levels.

It's convenient to be able to see the fluid color but that is not the reason for the sight glass.

***

As I said before; Color, Ginger Ale, good to go. Iced Tea, not good to go.
I have used jar and hose and done in 45 minutes. 

[sandy]

Robert: Using my bleeder tool, I've done 3 pickup trucks and too many motorcycles to count. No problems with any of them. By using the alcohol, you absorb the moisture in the system and flush it all out. I wouldn't use my method without a bleeder tool. Either the Mity-Vac or the pneumatic tool I have.

Sandy had it right Dot4 is the stuff I use Castrol GTLMA some fluids do say synthetic on them when they are dot 3 and dot 4 but the dot 5 stuff is usually silicon and not interchangeable with the dot3 and 4. Just to add to the confusion not all dot 5 are silicon either just for info. I wouldnt recomend pulling all the fluid out and letting air into the system as this causes you extra work and the results are really not any better. If you let air into the lines its harder to get out than just letting the fluid flush out the lines and sometimes its a pia to get all the air out. Take all the fluid out of the reservoir and refill with fresh fluid keep bleeding either by mighty vac or bleed screws or whatever till the fluid comes out clean of course refilling your reservoir as you go. Brake fluid is hygroscopic meaning it absorbs liquid this is done because there is always water in the brake system because of water in the air or condensation. So the fluid absorbs this water so it doesn't sit in the system and corrode the one spot it sits on possible causing failure. As this process is happening the fluid goes through changes these are darkening of fluid colors and lower boiling point. Boiling point is important because brakes create friction that creates heat so that heat is transferred to the fluid and it boils which causes air that in turn causes loss of brakes. Some never change their brake fluid from day a but some its done to spec and I haven't seen to many difficulties from those that are lax. But from the diligent their brakes are more responsive give a more positive feel and brake parts usually dont go bad.

[piper51]

Again, thanks for all the replies. I'll let you know if I have a problem. Going tomorrow to get a mity-vac and have at it. Next  might be a valve adjustment, but then again maybe not. piper.

[Robert]

Sandy that's text book and old school and honestly I have never seen anyone do that. The time and the steps needed are pretty much a waste in my opinion after seeing the results of years of doing it the easier way. When the change came from r12 to 134 the correct procedure was practically to replace the entire a/c system. Since then things have changed , the correct way is to add some of the correct oil be sure to evacuate the system well and recharge using the correct amount of refrigerant. It works well without much added cost or time. After bleeding a system with a mighty vac or just the old way of pressing the brakes to push the fluid out I have not seen any reason to do it any other way. The brake components hold up the brakes work well and the fluid is a good color. I have seen contaminants come out of the system and after knowing the properties of the brake fluid that if you get it on your hands it dries them out I have no fear of water or contaminants remaining in the system. You have to wonder how much alcohol is left in the system even after flushing it  out with brake fluid. Plus although the brake fluid and alcohol do mix what will the alcohol take out of the system that the brake fluid wont and how much alcohol will remain in the system or how much brake fluid do you really have to run through to get rid of all the alcohol? It will boil at a very low temp so you cannot leave it in the system. Now if you change from silicon to regular fluid I can understand it. The alcohol will cut the silicon and flush it out then bleed with regular fluid and your done. For me to feel comfortable with a regular flush I have to use two pints to a quart of fluid. Your way would take double the amount and the alcohol on top of that plus the longer time you deal with brake fluid the greater the chance of getting it on a painted surface. Plus if you totally drain the system the air that gets in is sometimes very hard to get out.  So I applaud you that you do this but this is my explanation as to why I dont and dont recommend it. Most who do their own maintenance want  a easy way to do good quality maintenance that holds up I cannot see making them jump through hoops when the result is ambiguously better.