Brake and Clutch Fluid level check

Joined
Aug 11, 2014
Messages
91
Location
Lake Zurich, Illinois
Bike
04 ST1300
What is the correct procedure to check the brake and clutch fluid levels on the MC on the handle bars. Here is what I do.

Clutch MC: Turn the handle bars all the way to the right to achieve a level position for the MC and then add the fluid to between the Lower and upper marks. This usually leaves a little bubble. Although when the handle bars are straightened there is more space in the MC compared to when it was turned all the way to the right.

Brake MC: Turn the handle bars all the way to the left to achieve a level position for the MC and then add the fluid to between the Lower and upper marks. This usually leaves a little bubble. Although when the handle bars are straightened there is more space in the MC compared to when it was turned all the way to the right.

Show below are the levels for the Brake MC on the left with the handle bar turned all the way to the left and the clutch MC with the handle turned all the way to the right.
 

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Nothing - I'm fond of IBC myself but when your hydraulic fluid is amber or brown it's probably in need of replacement.
Except that, due mostly to marketing I suspect, this is no longer the easy truth that it used to be as brake fluid comes in many shades of different colours now. What I use to consider to be old looking brake fluid I have seen coming straight out of a new sealed bottle. I have even see brake fluid with a distinct red hue, which is fine as it is still easy to distinguish when it begins to discolour due to normal contamination. What I find pretty dumb is manufacturers who make brake fluid that has a colour that makes it look like it is beginning to get contaminated when it is new, making it that much more difficult to tell what state the brake fluid is in.
 
What is the correct procedure to check the brake and clutch fluid levels on the MC on the handle bars. Here is what I do.

Clutch MC: Turn the handle bars all the way to the right to achieve a level position for the MC and then add the fluid to between the Lower and upper marks. This usually leaves a little bubble. Although when the handle bars are straightened there is more space in the MC compared to when it was turned all the way to the right.

Brake MC: Turn the handle bars all the way to the left to achieve a level position for the MC and then add the fluid to between the Lower and upper marks. This usually leaves a little bubble. Although when the handle bars are straightened there is more space in the MC compared to when it was turned all the way to the right.

Show below are the levels for the Brake MC on the left with the handle bar turned all the way to the left and the clutch MC with the handle turned all the way to the right.
Your method is just slightly off.
Let me explain, if a bike has handlebar risers, the level that appears in the window will be incorrect.
Do not use the lines outside of the master cylinder housing for the correct level of fluid.
INSIDE the housings, on the front wall, you will see an investment casting line across the housing, this should be used for the correct level fill indicator etc.
 
What I find pretty dumb is manufacturers who make brake fluid that has a colour that makes it look like it is beginning to get contaminated when it is new, making it that much more difficult to tell what state the brake fluid is in.
You have to look at this from a marketing perspective and ignore the safety implications.
 
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