Clutchoil synth or mineral dot 4

[MickDB1]

As my slave cylinder has gone tits up
could I have caused this by changing the hydraulic fluid to dot 4 synthetic
or would it just be a case of it had come to its time
I have changed the slave but thought I would ask before filling with synthetic dot 4 again
Thanks for any help

 

[MattW]

As my slave cylinder has gone tits up
could I have caused this by changing the hydraulic fluid to dot 4 synthetic
or would it just be a case of it had come to its time
I have changed the slave but thought I would ask before filling with synthetic dot 4 again
Thanks for any help

What does it say to use in the riders handbook?

(mines a cable clutch so I haven't had to mess with clutch hydraulics)

 

[MickDB1]

My workshop manual on a CD says dot 4 but is not specific
Front Brake Fluid Reservoir
1. Put the bike on the centerstand.
2. Turn the handlebar straight ahead so the reservoir on the right handlebar is
level.
3. Check the fluid level in the sight glass of the reservoir.
4. Add only DOT 4 brake fluid if the level is at or below the LOWER level mark.
It says same for clutch
Dont have a handbook
Thanks up to now

 

[DrFarkoff]

On 1150's the clutch fluid was DOT 4

on 1200's it was a mineral based oil which was then changed to another hydraulic fluid Vit**** something like that

If you are loosing clutch fluid then you have a problem at the slave cylinder end

Seals / leaking fittings corroded pipes etc etc

So DOT 4 is perfectly okay in 1150s

 

[(RIP) DitchWater]

Motorworks sell DOT 4 Synth for brakes HERE (part way down the page) and I presume it should be okay for the clutch as well.

AFAIK nobody buys two types of fluid for the 1150's hydraulic systems.

I usually buy the cheap DOT 4 and don't bother with the special stuff.

Also, I have been informed that old fluid is a killer for clutch slave cylinders, and other seals, and since I lost my last one I'll be doing more frequent services.

Good Luck.

 

[davegs]

Fluid

It's dot 5 that will mess it up, dot 4 is the correct stuff.
Dave GS

 

[MickDB1]

Thanks for the advice up to now
but
the questions were
Could putting synthetic dot 4 have caused the seals to perish

Should I fill new slave cylinder and clutch system with Dot4 mineral
or Dot4 synthetic
Thanks for patience with me

 

[DrFarkoff]

Mick if you find DOT4 mineral it will surely be well past it's sell by date

I do fluid changes for folks and use DOT4 synth because that is all I can find locally and so far I haven;t had any problems

 

[MickDB1]

Thanks for that everyone
I just didnt want to bugger up the seals on a new clutch slave cylinder by not asking if they are OK with Synthetic Hydraulic Fluid
Back to the shed
Great site this is top folks helping each other
Best 15 quid yer can spend on motorcycling

 

[wessie]

What you haven't said is how old & at what mileage the original slave cylinder failed at. My 1150 is 11 years old - if one of the master cylinders packed up next week then I'd put it down to old age rather than anything done by me or my regular mechanic.

As others say, as far as the new one is concerned, any DOT4 fluid will be fine, regardless of the mode of manufacture.

 

[warmshed]

DOT 3 and DOT 4 are poly-glycol-based fluids and can be mixed with each other. DOT5.1 can also be made from a similar base. The dot 4 is less harmful if you drip it on your paintwork, due to the inclusion of borate esters.

You can mix Dot3 and Dot4 and Dot5.1 (if not silicone based).

None should be mixed with Dot5 which is silicone based.

Dot4 is not compatible with mineral based fluids.