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Brake/clutch fluid change?

9K views 29 replies 9 participants last post by  Mark Carlton 
#1 ·
Anyone have any special advice, what to be careful of etc, on how to do a brake fluid and clutch fluid change?
 
#6 ·
5.1 is ok with 4.....do NOT use 5. Actually, 4 will work perfectly, last longer than 5.1 and cost less.....unless you are racing, then go for the higher temp stuff. Your bike came with 4.

Noel's method will result in faster and easier bleeding with less chance to mix old and new fluid.....using less fluid, too.

Keep clean water handy and wash up or wipe off any spills quickly!
 
#7 ·
I use DOT 4 period......

cleanup with a water/alcohol mix ~ 30% alcohol works great

you can cheat a bit and use C clamps on the calipers(or wedges) and

slave

if you saw me fill and bleed a new system.......you'd go WTF...... I don't

use the bleed fittings at all

:naughty::naughty::naughty:

except on the retarded POS Brembo radial M/Cs

:popcorn:
 
#12 ·
Regardless of whether you push your pistons in or not,when the system returns to its "on the bike" state, the volume of fluid used will be the same. The pistons have to push out to the discs and the slave has to regain enough fluid to push the rod to disengage the clutch.

There is a possibility of introducing air, not that you, Noel, would do that due to your experience, as the reservoir level drops refilling the system.

I prefer to bleed the system in stasis using a vacuum bleeder at the actuated end of the system. Not everyone has that capability, though.

There are many ways to skin this cat.:smoking:
 
#10 ·
I drape a damp cloth over the vulnerable areas of the bike.
Remove the reservoir cap and bleed the fronts from the furthest away caliper first. I normally drain the res to a low level first.
I dont mind shoving fluid through around the pistons particularly to force out moisture that may have condensed throughout.
Do 5.1 has a higher boiling point but has a greater affinity for moisture .
I change my fluid each year on all my bikes. Fluid is cheap works much better than water and brake parts are expensive...
joe
 
#16 ·
#17 · (Edited)
I know the guy in the video was using the wrong 'terms' when describing the process he was performing...., however 'what' he performed was correct!.

In any case each to his own..., and this is tool works perfectly for me ....., every time.
Others are more than happy to 'pump the brake lever'...., whatever works for you is the best.
 
#18 ·
Thanks, I understand the principle! I note the manual says it is not necessary to remove the calipers if you have the tool to separate the pads on the 2007 model But it does say it is necessary to remove and refit the right clip on whilst activating the brake lever...???
 
#20 ·
That is to ensure the master cylinder juncture to the brake hose is not higher than the fluid port in the master cylinder bore.

Lots of ways to "correctly" flush and bleed hydraulics.
I like Noel's method since you minimize old fluid in the system at the outset. I have a mitivac....works OK. Also have a vacuum system using air pressure at 90 or higher psi....works REALLY well.

But if I am using expensive high end fluid instead of AutoZone basic economy (yes, Virginia, there IS a difference in brake fluids even though they may all have the same "DOT rating"), then I go the hand route, and Noel's method. Less waste.
:conveyer:
 
#21 ·
The viscosities are different, the DOT5.1 is made for ABS brake cars systems(more fluid), not good for bikes( without assyst drums-pumps, electrovalves etc).
There are two DOT4 ,one for street use and another one for race use (RBF600 etc) The last one is more hydrophylic behaviour , need an exchange every six months.
When a bike falls on circuit , it's common to purge all brake fluids again, it's logic.
 
#22 ·
The viscosities are different, the DOT5.1 is made for ABS brake cars systems(more fluid), not good for bikes( without assyst drums-pumps, electrovalves etc).
You're thinking of Dot 5 Christo ?
 

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#25 ·
Hence you still have to change it...unless you compress the pistons with the bleed screws open...then you just have to replace the volume.
 
#26 ·
I always open the bleeder and compress the piston(s) when even just changing brakes.
On any vehicle with that type of system. always moving some of the old fluid out.
Even between the fluid changes.
I am a believer in regular brake fluid changes.
I have repaired many systems that were just gummed up with crap from never changing the fluid!

Ed S :)
 
#27 ·
bleeding POS

Chuck;

if I push the pistons back in and hold them......

almost of the dirty fluid is in the M/C which get sucked out and cleaned,

now I refill the M/C with clean fluid and bleed the calipers/slave

there is less dirty fluid to mix with the clean, so I use less new fluid

you should see me bleed new/dry systems.....I don't use the bleed

fittings....except on the retarded Brembo radial M/Cs with the return port

on the side:wtf::wtf::wtf::wtf::wtf:
 
#28 ·
I'm just lazy. I don't move the pistons unless I'm changing pads or removing the calipers from the bike.

I simply hook up the vacuum bleeder to the system at the farthest point, remove the reservoir cover, actuate the bleeder and open the bleed valve a bit to get a nice rate of level change, then pour in fluid as the vacuum bleeder does the work. Clear clean fluid shows up in the bleed hose, close the bleed valve, trip off the vacuum bleeder, top off the reservoir, restore the reservoir cap, done.

I can swap fluid in the front brakes and the clutch in under 15 minutes. Some rears are a PITA because of the reservoir location.

The only challenge for some would be having a air source to drive the vacuum bleeder. Those manual Mitey Vacs solve that.
 
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