Clutch lever......lost pressure issue

[Huskyfly]

Hello all,

Well I was trying to meet Woodschick & Eric this evening and my 630 was acting up. I lost about 70-80% of pressure in the clutch lever and almost couldn't change gears/disengage the clutch!! Luckily I wasn't around too many cars when this happened but man did it catch my attention. I ended up pumping the lever while stopped and it seem to get a little pressure back but riding back home I lost most of the pressure again. Now, I have 1900 miles about 80% of it off-road....I just rode all day at Hollister on Monday without any issues.....other than me dropping the bike trying to do the enduro-cross mini track they had (dumb move on my part.....the bolder field got me).

My 630 has been a gem up to this point. I'm wondering however if I missed some kind of routine maintenance with this. The bikes never leaked a drop of anything best I can tell......although I didn't wash it from day one until this evening. I'm wondering if anyone else had something similar happen? Most people seem to think I just have air or a leak in a seal but everywhere I trace the line I don't see any issues? The clutch recall was already done on the bike in case anyone thinks of that. Thanks for your time.

 

[willie]

Did you check the oil level in the clutch tank? You may have a leak in the slave cylinder as these are difficult to detect. If level is OK then bleed system to eliminate any bubbles. If still not working properly you have a problem with the slave or master cylinder. My guess is air in the line!

 

[Busted RS]

[quote="I lost about 70-80% of pressure in the clutch lever and almost couldn't change gears/disengage the clutch!!
[/quote]
G'day Huskyfly, I had that exact thing happen last weekend. Although I did not notice any leak, turns out the Clutch Master Cylinder must have had a slow leak (I have never checked the fluid level, never seeing any leak) Took the top off the reservoir and sure enough, no fluid. That will do it. Turns out the oil runs down the back of the clutch handle and drips off the end of the lever. Filled it up, bled the line and the clutch works fine again. Have now purchased new seals to fix the problem.

Power on regardless.

 

[jtemple]

If your master cylinder is leaking you will see a light film of oil all over your lever. If your slave cylinder is leaking into the engine, you won't see anything. Squeezing the clutch lever will just inject clutch fluid into the engine.

 

[Huskyfly]

Thanks for everyone's help!!Yes Busted RS, that describes my situation exactly. The dealer will look at it either tomorrow or Saturday. BTW, is this common with bikes with Hydraulic clutches? Is this something to check within a certain interval? The bike's been perfect up until now, not a drop of anything best I can tell. Hmmm.......

 

[Huskyfly]

If your master cylinder is leaking you will see a light film of oil all over your lever. If your slave cylinder is leaking into the engine, you won't see anything. Squeezing the clutch lever will just inject clutch fluid into the engine.

I haven't seen any leaks.....this sounds bad!! Is it wise to do an oil change too to get rid of the potential problem of mixing oil and fluid???

 

[jtemple]

I haven't seen any leaks.....this sounds bad!! Is it wise to do an oil change too to get rid of the potential problem of mixing oil and fluid???

It's just a little bit of mineral oil. I don't think you're looking at any sort of critical problem here. You might want to pull your slave cylinder and take a look, though. If you discover that the slave is leaking into the engine, replace the slave cylinder, change your oil, and go riding.

 

[Huskyfly]

It's just a little bit of mineral oil. I don't think you're looking at any sort of critical problem here. You might want to pull your slave cylinder and take a look, though. If you discover that the slave is leaking into the engine, replace the slave cylinder, change your oil, and go riding.

So the bike will think I'm trying to break it in again.....got it!

 

[CJBROWN]

A pint of mineral oil is like $4 at a drug store. 99% pure for constipation. Yep, it's pure, straight, mineral oil.

Everyone should definitely replace the oil if there is any discoloration at all. Mine looked like it had some kind of white jelly floating in the reservoir. Easy to flush from the top down. Bleeds just like a brake cyl.

I'm thinking mine got some moisture in it and it was causing the oil to leak out the seal at the lever. It would drip. It was also over full. Sucked out the old with a syringe and then flushed new oil thru the slave. After flushing it out it hasn't acted up since.

I've had a number of hydraulic clutches and have never had a problem with them. I'm surprised to hear of this on the Husky. It is a Magura system, so it's not like it's some new fangled thing Husky dreamed up.

 

[jtemple]

I have never had a hydro clutch until the 630. No clutch has ever given me more problems. The action is buttery smooth, but some times I wish I had a cable, for simplicity's sake.

 

[Dirtdame]

A pint of mineral oil is like $4 at a drug store. 99% pure for constipation. Yep, it's pure, straight, mineral oil.

Everyone should definitely replace the oil if there is any discoloration at all. Mine looked like it had some kind of white jelly floating in the reservoir.

That's why I switched back to Magura Blood. When I was using the plain mineral oil, I got slimy goo in my hydraulic system. Never had that with the Magura fluid.

 

[SilverBullet]

I have never had a hydro clutch until the 630. No clutch has ever given me more problems. The action is buttery smooth, but some times I wish I had a cable, for simplicity's sake.

I can tell you never owned a 610. It eats clutch cables so bad owners buy them two or three at a time.

 

[Huskyfly]

The shop replaced the seals at the bottom under warranty. The bikes fine but I think I'll pick up some extra oil just to keep with me. I too have heard that, in general hydraulic clutches give little or no problems. I was a little taken by this acting up. No biggy until, or if, it happens again.

 

[jtemple]

I can tell you never owned a 610. It eats clutch cables so bad owners buy them two or three at a time.

I never had a single problem with a clutch cable on a street bike. Different animal, though, I suppose.

 

[SilverBullet]

I never had a single problem with a clutch cable on a street bike. Different animal, though, I suppose.

I neither on any bike but the 610 definitely has an issue so I just mentioned as that bike is so close to ours and if your 630 didn't have a hydraulic clutch it would have the 610 clutch setup. When I was searching used 610's every one I found for sale came with one or two extra clutch cables. First ride I was on with a 610 in attendance its clutch cable went out the first hour.

_

 

[LRPct]

I can tell you never owned a 610. It eats clutch cables so bad owners buy them two or three at a time.

Not true.. just a gross overgeneralization by your small piece of anedectoral experience.. I got 13k miles out of my stock cable, and so have many others I know.. I guess I can make the statement that they ALL last that long and if not its cause of an owner that doesn't even bother to look for proper cable routing... I can tell you're one of them.. :P

 

[SilverBullet]

Not true.. just a gross overgeneralization by your small piece of anedectoral experience.. I got 13k miles out of my stock cable, and so have many others I know.. I guess I can make the statement that they ALL last that long and if not its cause of an owner that doesn't even bother to look for proper cable routing... I can tell you're one of them.. :P

I don't own one. This is from posts here and on Advrider. Stated over and over that Husky, Motion Pro and Barnett cables all fail early, sometimes within 1,000 miles. I'm just glad the 630 clutch is hydraulic.

_

 

[CJBROWN]

That's why I switched back to Magura Blood. When I was using the plain mineral oil, I got slimy goo in my hydraulic system. Never had that with the Magura fluid.

Really? Poor assumption, IMO.
The 'goo' was on the new bike, factory fill.
What do they use? And what is in Magura fluid besides mineral oil?
What is in the mineral oil that creates the 'goo'?

I have owned at least 3 bikes with a hydraulic clutch, over a period of a dozen years and no issues. Now, if you had some kind of scientific basis for your opinion then I would have much more readily accepted it.

 

[Dirtdame]

I have owned at least 3 bikes with a hydraulic clutch, over a period of a dozen years and no issues. Now, if you had some kind of scientific basis for your opinion then I would have much more readily accepted it.

Well, let's see....I used Magura Blood in my KTM for 4 years and never saw anything like that happen. Then I used Magura Blood in my TE for 4 years and never saw anything like that happen. Then I flushed all that Magura Blood out of the system and ran some plain mineral oil from the drug store...and in less than six months, I had goo in the master cylinder and the lower piston housing. I just report what I see happen. I don't run it through a lab analysis. I'm obviously just an idiot, not a scientist.

 

[CJBROWN]

Well, let's see....I used Magura Blood in my KTM for 4 years and never saw anything like that happen. Then I used Magura Blood in my TE for 4 years and never saw anything like that happen. Then I flushed all that Magura Blood out of the system and ran some plain mineral oil from the drug store...and in less than six months, I had goo in the master cylinder and the lower piston housing. I just report what I see happen. I don't run it through a lab analysis. I'm obviously just an idiot, not a scientist.

What I have a problem with is the deduction that since you ran something successfully in two different bikes and then had an issue with a different fluid that it is the fault of the fluid. If you had come back with something like what the different properties and ingredients are of the two fluids, that one had some additive to prevent moisture or something like that, then it might make some sense and lend credence to your assumption that one is better than the other.

That's like saying I ran one kind of oil in two bikes successfully for a long time and then used a different oil and it blew up - so it must be bad oil.

Egads. Ooh boy.




EDIT: So I got my curiosity up and did some research on this and it has been discussed ad infinitem on ADV, to death really. All the KTM's and a bunch of BMW's have these clutches on them and there's all kinds of issues but nothing that isn't easily remedied. If you want a little reading or a LOT, just search on google like this: site:advrider.com mineral oil clutch - you'll get hundreds of discussion links.

The hydraulic clutch is a closed system with close tolerences so a light viscosity fluid that is non corrosive and non seal softening or hardening is what's required since the pistons have o-rings on them to seal. The factory's idea was to make sure we didn't put brake fluid in them so they specified mineral oil. Magura Blood and Royal Blood is mineral oil. And Magura makes the same units for all of the BMW hydraulic clutches as well. Of course BMW has their own fluid too for like $22 for a couple of ounces.

Mineral oil has a boiling point of 740deg and is non hygroscopic, which means it does not absorb water like Dot brake fluid does.

Since the system is closed any light oil will work in them, fork oil, hydraulic jack oil, sewing machine oil, ATF, power steering fluid for BMW and VW, baby oil, even olive oil. The latter being less desirable for stability, and baby oil because it's purity and viscosity aren't well known. But lots of riders have been using pure mineral oil like baby oil or drug store mineral oil for years without incident. The Magura or Shimano (for bicycle brakes) are the right viscosity and so are obviously recommended. It is generally said that these system don't require any kind of regular maintenance nor fluid changes since there is no heat involved like for brakes, and no water gets in them. Of course it makes sense to check your fluid level so if the slave leaks you'll see the level drop so you can fix it before you are left clutchless.