clutch fluid flush and fill advised every 12 months

I just flushed and filled my clutch fluid. sorry no photos....
Despite completing this simple procedure exactly 1 year ago, the rubber baffle was coated with significant condensation (water) and the base of the master cylinder had a thin sediment of dark crud.

Manufacture recommendation is normally 2 years. My bike is stored in a garden shed but it cant escape the condensation in the air of Melbourne winters...



Unless your name is Jay Leno and you have a heated humidity controlled garage for your 600 vehicles...

The job takes 20 min with my ?Mighty Vac? pump! it makes it a breeze, flushed 4 reservoirs worth of dot 4, ?Castrol high performance? hydraulic fluid thru the clutch line, all for $10.00 and peace of mind, till next year.

I hope to enjoy smooth gear changes.

:yes: Sounds like you can do the job quickly now.

When I've checked the 'water' droplets on that rubber diaphragm, they were normal DOT fluid. An easy way to tell is to blot the droplets onto a clean paper towel and see if they've evaporated the next day (if evaporated > largely water).

What fluid are you using? I've found Valvoline Synthetic DOT 3 & 4 has been excellent in mine, not discoloring and staying clear. You might give that a try next time.

I ride enough miles annually to do the clutch and brake system on mileage, not time, and finding condensation on the rubber reservoir seals is a regular occurrence. The only time I found crud in the reservoirs was the first time. I alternate using Prestone Synthetic and Valvoline Synthetic. One is amber and one is nearly clear so when I bleed each line I can see when the old fluid is flushed out and new fluid is coming out of the circuit. I can completely flush and replace both clutch and brake systems with two 12 oz bottles.

Because the clutch bleeder is so close to the clutch lever I just use the manual method of pump and close and save the MityVac for the circuits too far apart for me to get a hand and a wrench on each one.

thanks Bakerboy for the advice, used Castrol high performance dot 4 (red plastic bottle, green liquid)

I bleed the clutch at least twice as often as the brakes, just because it bugs me when one site glass is darker than the other. lol
Agree that the "condensation" isn't actually water, the systems are pretty sealed.
My theory as to why the clutch fluid seems to darken before the brake fluid is because it gets actuated probably 5-10 times as much as the brakes.

playfair said:

My theory as to why the clutch fluid seems to darken before the brake fluid is because it gets actuated probably 5-10 times as much as the brakes.

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More due the slave-cylinder being continuously exposed to heat from the engine/oil down there in the clutch housing.

ST1100Y said:

More due the slave-cylinder being continuously exposed to heat from the engine/oil down there in the clutch housing.

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+1, those lines are also very close to the engine and frame and the brake lines are somewhat less exposed to the heat plus contain more volume so dissipate that heat better.

Ok, thanks for the reminder, grabbing my coffee and heading out there to dry out the rubber reservoir seal, also I'll excavate the old oil out of the reservoir and add new oil. Not sure if I will have time to do a bleed.

I also like to keep my fluid clear and not letting it get to the dark side. It is an easy job that does not take to much time to complete.

Al Gully said:

Ok, thanks for the reminder, grabbing my coffee and heading out there to dry out the rubber reservoir seal.

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Job took a little longer than I thought. Seal was soaked with water on the top side. Took the heat gun and dried it off. Drained the reservoir and put fresh oil back in to the proper level. Boxed it up and tried it out. No big change in feel, but was the lever ever sloppy. Took it apart and found that I need the 2 brass bushings. Hoping I can buy them from Honda. Also, the slop up and down was pretty bad also. Brought my feeler gauges out and found that the play in between the ears was about 0.009". So I made up. 0.005" shim from the shim stock I had laying around. Added some water resistant grease to all the pivot points and boxed it up. Wow, what an improvement. Now I just need to get those 2 brass bushing to snug the rest up.

The bushing the pushrod goes into is available (22885-MB0-006) but the pivot bushing is pressed into the lever. A new lever is required (53178-MCS-305) for that one. If the chrome is galled on the pivot bolt it is 90114-MA5-671.

dduelin said:

A new lever is required (53178-MCS-305) for that one. If the chrome is galled

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Thanks Dave for the numbers.
Gonna get my brother to make up a drop in brass bushing for the lever. I just need to punch it out and give him the OD. I can get the ID from the bolt and length just by taking the lever off. The chrome screw is in perfect shape, no need to replace the 8mm screw. Maybe get him to make up a few and then add them to the freebies draw Mellow puts on each month.