2014 498RR - Clutch fade?

I did a search and found nothing, but apologies if this has already been covered.  For the first time ever, I experienced "clutch fade" on my Beta last week while riding near Mammoth at ~9.000' in elevation.  I was riding slow technical rocky stuff for a bit, the cooling fan came on, but I wasn't really abusing the clutch or motor per se.  The clutch lever action suddenly became "floppy", as in the lever was just flopping around with no resistance until I pulled it in more than half way.  The clutch still kinda worked, but it was unusually grabby.  Immediately after I got through the technical section the bike must have cooled off a little and the clutch action returned to normal feel.  I believe this is what's referred to as "clutch fade", right?  Is this a function of the high elevation, or is there a leak in my hydraulic clutch line?  I've never felt this before and the bike only has 1,200 miles on it.  One guy said to check the o-ring on the slave side.  Another said my clutch line needs to be bled.  But why would the feeling return to normal within seconds of getting through technical stuff?  Thanks

The reason you got your clutch back was because the fluid cooled down and quit boiling. At 1200 miles I figure your bike is over a year old or close to it. Did you flush the brakes and clutch when you took delivery of the bike? That's one of the first things I do. Some here might disagree with that. It's cheap insurance IMO.

 

Mine did the same thing on a extreme ride in Big Bear last month. Lost the clutch lever in the nasty clutch abusing rock sections at elevation. I came home and flushed out the fluid and it works perfect. Got my bike up to 270 degrees on a short ride last week with no clutch fade.

 

For now all I had was regular dot 4 on hand. If you want the very best, use Motul 600 or 660. If you use these fluids you must flush your system twice a season. The absorb moisture a lot quicker than the standard brake fluid.

 

FWIW, I had the Motul 600 in my clutch when I lost the lever. It was not flushed in over a year. For me it's a fair trade off for the best performance.

Edited by ballisticexchris

Hmmm... my 10 year old GasGas has original hydraulic clutch line fluid in it, never been bled, and it's always worked perfectly, never faded.  My 1 year old Beta already needs new clutch line fluid or needs to be bled?  Doesn't seem right.  Should a clutch line be bled or fluid replaced every year?  Seems excessive considering it's a closed system.  Thank you

I saw VWprostock mentioned the same on his 350. Are you still in warranty? I have heard mention of incorrect fluid from the factory destroying the o-rings in the master or slave? They might cover it anyway if it was defective. 

 

I haven't experienced anything similar, but I haven't been in those conditions either.

 

When I think of "clutch fade" it typically refers to slippage due to heat. 

 

I think what you describe would be "loss of lever".  Either way it sucks to lose control of it when you need it most.

Hmmm... my 10 year old GasGas has original hydraulic clutch line fluid in it, never been bled, and it's always worked perfectly, never faded.  My 1 year old Beta already needs new clutch line fluid or needs to be bled?  Doesn't seem right.  Should a clutch line be bled or fluid replaced every year?  Seems excessive considering it's a closed system.  Thank you

 

WOW!! That's really strange. Even though it's a closed system it still collects moisture. 10 years on the same fluid just blows my mind. The first thing I do to my bikes is change out fluids after taking delivery and twice a season there after. To be honest I can't explain why. I just know what works for me. Twice a season with Motul 600 has served me well for many years. Whenever I go more than a year I end up having issues with spongy brakes and clutch.

 

At the very least I would highly recommend you do the flush. It's cheap and sure beats tearing into the slave cylinder. While your at it you might consider getting this KTM part to make it easy to do flushes in the future. When installing this just make sure you are quick with the wrenches. Keep the MC cap on and pull the banjo bolt and put this in it's place. Then simply pump and flush or back bleed if you have a syringe.

 

IMG_0890_zps6xojogey.jpg

 

IMG_0891_zpsccllpfbd.jpg

I saw VWprostock mentioned the same on his 350. Are you still in warranty? I have heard mention of incorrect fluid from the factory destroying the o-rings in the master or slave? They might cover it anyway if it was defective. 

 

I haven't experienced anything similar, but I haven't been in those conditions either.

 

When I think of "clutch fade" it typically refers to slippage due to heat. 

 

I think what you describe would be "loss of lever".  Either way it sucks to lose control of it when you need it most.

 

That's one of the reasons I really like the Rekluse!

You surely overheated the clutch fluid, you could recovery it instantaneously right there in the track jus throwing some cold water in the slave unit. Ive seen this happen in my own 350 and some others too, usually 4T. Cause could be liquid boiling properties were altered, either because it is old, has water, or just motor was so hot that heated the slave in excess.

Edited by BetaRRsouth

You surely overheated the clutch fluid, you could recovery it instantaneously right there in the track jus throwing some cold water in the slave unit. Ive seen this happen in my own 350 and some others too, usually 4T. Cause could be liquid boiling properties were altered, either because it is old, has water, or just motor was so hot that heated the slave in excess.

 

Interesting, thanks.  I definitely recall riding more difficult terrain at/around sea level on the bike without the same phenomenon.  In theory, the motor should actually run (slightly) cooler at the higher elevation due to a rich condition, but the slave and fluid must have overheated nonetheless.  Sounds like it's time to replace the clutch line fluid.  Thanks guys.

Well, I really dont know the root cause, but Im completely sure it is overheating because you drop some cold water in the slave and you see it boil, clutch recovers instantaneously. I replaced the fluid for a top quality -competition one, and never had the problem again

Maybe someone can investigate this further, I just sold my bike two weeks ago

Hmmm... my 10 year old GasGas has original hydraulic clutch line fluid in it, never been bled, and it's always worked perfectly, never faded.  My 1 year old Beta already needs new clutch line fluid or needs to be bled?  Doesn't seem right.  Should a clutch line be bled or fluid replaced every year?  Seems excessive considering it's a closed system.  Thank you

If I'm not mistaken most brakes are also closed systems also as much as any hyd clutch system is, and sometimes everything needs a fresh bleed fresh juice, no telling what the factory installs. But it's worth it to change it out.

I got a Rekluse installed by Beta USA, so who knows what they installed for juice...

BTW, the heat emitted from the mass of a hot 4-stroke might just be More than a GG-2 stroke, just sayin....

BTW, the heat emitted from the mass of a hot 4-stroke might just be More than a GG-2 stroke, just sayin....

 

Very true, gotta be the difference.  Thanks again for the responses guys!

Higher elevation = lower atmospheric pressure so any air bubbles would expand (just like if heated). Change your fluid.

Higher elevation = lower atmospheric pressure so any air bubbles would expand (just like if heated). Change your fluid.

 

But... only if there was a leak in the system, right?  Failed o-ring(s), loose master cylinder reservoir cap, or tiny pinhole in the clutch line?  Considering it is (should be) a totally closed/sealed circuit, elevation/atmospheric pressure shouldn't affect the properties of the fluid... right?  I put my ear to the clutch lever perch just now and gave it a few squeezes, and I could hear some hissing as fluid moved through the master cylinder and some very tiny bubbles appeared around the little rubber boot that the lever pushes in.  I washed the bike yesterday, so maybe they're just from a little leftover water in the perch.  I do believe there is some air in there, but I want to make sure I determine how it got in before I just put new fluid in.  I'm not (yet) familiar with bleeding lines, so pardon my ignorance of how air got it there in the first place.  Anyone have a good YouTube video or online instructions on how to upgrade fluid and bleed a hydraulic clutch line?

Almost every spring the front brake on my KTM goes right to the bar, nothing no brakes.  Don't know why.  All I have to do is tape the lever to the bar, spread the pads pushing the piston back in and let it sit overnight.  Next day brakes will work like new.  Obviously air got in but I can tell you there are no leaks so I'm not worried about it, it'll be good for the year after that.  Just sayin that sometimes air enters a system for some unexplained reason that you may never find and it's nothing to fret about.  You would know if there was a leak or a problem. 

Hmmm... my 10 year old GasGas has original hydraulic clutch line fluid in it, never been bled, and it's always worked perfectly, never faded.  My 1 year old Beta already needs new clutch line fluid or needs to be bled?  Doesn't seem right.  Should a clutch line be bled or fluid replaced every year?  Seems excessive considering it's a closed system.  Thank you

I change brake fluid every 6,000 miles or once a year, which ever comes first on every bike whether road or dirt.

The clutch system (and brakes as well) are NOT closed systems. If you look carefully at the caps there are tiny passages machined in for air to enter. There is atmospheric pressure on top of the diaphragm.

 

I recently had a similar "loss of lever" situation with my 350 Factory. In the course of flushing the old fluid, filling it with Motul 660 and bleeding it I found a little piece of rubber that the cap screw had separated from the diaphragm in the fluid under the plastic strainer in the master cylinder. It quite possibly had blocked one of the ports, similar to what the AJP masters on GasGas' used to do.

My gasgas has boiled over..and the clutch goes floppy..sounds the same as yours....when the bike cooled the clutch came back.. same thing happened when I have boiled my 525 rs in tight ugly trails.. 4 strokes of course run hotter than 2 stroke too but both boil and the clutch disappears until the bike cools again. Of course maybe I should have changed the hydraulic clutch fluid..and I didnt...but when my overheating issues were dealt with and or when I got gearing matched better so that I didn't use my clutch as much then my clutch has been fine ever since. I rode my 525 in a boulder filled riverbed when it was brand new and not broken in..(running extra hot)  going slow and slipping the clutch alot with a little higher gearing.. All the elements that are not a good idea to do. ktm rfs motors never were known to be cool running bikes anyway but I did all the wrong things to get my bike to boil at the beginning and have my clutch go away with boiling brake fluid.. :ride:  :naughty:  :ride:  :rolleyes:

I've learned a heck of a lot about my hydraulic lines lately, thanks guys!  I bought some Motul 660 for $22 bucks, watched a couple YouTube vids on how to replace clutch fluid (super easy but messy), and think I'm ready to move on this project - and probably will replace fluid on my other bikes, too.  BTW, Chris, my bike came with that zert fitting already installed... apparently a factory upgrade since your 2012 model.

I've learned a heck of a lot about my hydraulic lines lately, thanks guys!  I bought some Motul 660 for $22 bucks, watched a couple YouTube vids on how to replace clutch fluid (super easy but messy), and think I'm ready to move on this project - and probably will replace fluid on my other bikes, too.  BTW, Chris, my bike came with that zert fitting already installed... apparently a factory upgrade since your 2012 model.

 

Cool deal! I'm going with the 660 myself next bleed. The only other brake fluid that's better is the Castrol SRF. But then your talking over 60 bucks a liter for just a few degrees better protection. Also be aware that once you open the bottle it needs to be used right away. Almost no shelf life. Moisture starts creeping in from the time you crack it open (lowering the boiling temp).

 

Keep in mind when you start using the high temp fluid there is a huge drawback. You will have to bleed your system more often as it collects moisture at a rapid rate. I've found changing twice a season at the bare minimum for sufficient performance. 

 

If you have a syringe, back bleeding is the messiest but the best way to flush out all the old crap.

I've learned a heck of a lot about my hydraulic lines lately, thanks guys!  I bought some Motul 660 for $22 bucks, watched a couple YouTube vids on how to replace clutch fluid (super easy but messy), and think I'm ready to move on this project - and probably will replace fluid on my other bikes, too.  BTW, Chris, my bike came with that zert fitting already installed... apparently a factory upgrade since your 2012 model.

My 14 520rs also has the upgraded bolt.

I had a similar problem on a 2014 520RS 3400 miles and 110 hours this past Friday and Saturday. I ride at sea level. Twice my hydraulic clutch reservoir went dry on fluid. Thus I had no clutching ability. The first time I took brake fluid out of my RAM pickup, bled the air out and rode it 150 miles. I brought it home and flushed out the brake fluid and added MOTUL DOT 5.1 brake fluid. Bled the air out. Rode Sunday and in about 190 miles I had the same failure. Seems like its leaking out through those air vents molded into the cylinder cover. I am going to go get a new rubber gasket tomorrow and start from scratch again. Anyone have an idea on how much fluid should be in the reservoir. I'm think possibly only about 1/16 of an inch in depth. I hear people talking about another type of MOTUL brake fluid. Anyone have a problem with the DOT 5.1 I'm using? Thanks for your input.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now