Clutch lost pressure

[iyernat]

I rode the bike about 10 days back and had no issues and it was parked in the garage all the time. I tried to get on the bike yesterday and immediately noticed that the clutch has no pressure. I knew that It probably needed a clutch bleed (thanls to this forum). Bsed on the amount pf work involved and my ability to foul anything mechanical, I decided to go to the dealer for it. The dealer here is about 5 miled from my home and they came and picked up the bike and bled and refilled the clutch oil. I paid $81 for the pickup and the work. It was all done in 4 hours. I went and picked up the bike in the afternoon and all is well.

The mechanic told me that the entire oil had kind of frozen up in clumps and he had to vacuum it out with great difficulty.

How could this happen ?

 

[STurgisSTeele]

Could be a mixture of different DOT numbers. Or considerable amount of water collected in the system. (Not an expert, but I do play one on TV. JK)

John STeele
Peace and All Good

 

[okbobw]

I rode the bike about 10 days back and had no issues and it was parked in the garage all the time. I tried to get on the bike yesterday and immediately noticed that the clutch has no pressure. I knew that It probably needed a clutch bleed (thanls to this forum). Bsed on the amount pf work involved and my ability to foul anything mechanical, I decided to go to the dealer for it. The dealer here is about 5 miled from my home and they came and picked up the bike and bled and refilled the clutch oil. I paid $81 for the pickup and the work. It was all done in 4 hours. I went and picked up the bike in the afternoon and all is well.

The mechanic told me that the entire oil had kind of frozen up in clumps and he had to vacuum it out with great difficulty.

How could this happen ?

The slave cylinder can get really warm and the heating and cooling will cause the fluid to take on moisture and over time the fluid will turn into a sludge like gel.
it will generally settle in the lower part of the system but I have seen fluid in the master cylinder turn into a sludge as well.
I always take off the slave cylinder and really clean the piston area etc. Not that difficult to do and it can be done without taking off the rt. side headers.

.........I made the assumption that this is a ST1100 and my comment about not being too difficult applies. BUT if it is a 1300 removing the slave cylinder is a different story.......

 

[Me_cmc]

My $0.02: Why the H do bikes even have hydraulic clutches? What the f was wrong with a cable that might break, but you could carry a spare and replace in five minutes? Instead of hundreds of dollars to replace the slave when it goes, and constant maintenance. Yes, I know a hydraulic system is supposedly easier, I guess they say, but a cable gives better feel anyway.

 

[dwalby]

My $0.02: Why the H do bikes even have hydraulic clutches? What the f was wrong with a cable that might break, but you could carry a spare and replace in five minutes? Instead of hundreds of dollars to replace the slave when it goes, and constant maintenance. Yes, I know a hydraulic system is supposedly easier, I guess they say, but a cable gives better feel anyway.

I have been asking myself that question for decades, using the exact same logical reasoning you are using. The only possible argument is that the hydraulic system is self adjusting, but BFD, I can live without that luxury.

 

[Mick]

The mechanic told me that the entire oil had kind of frozen up in clumps and he had to vacuum it out with great difficulty.

I experienced this on the rear brake circuit of a 1993 VFR I bought about 15 years ago. The bike had very low mileage for it's age and had sat a lot. The fluid had such a dark color that it looked like it had never been changed. When I went to bleed the rear circuit, I had a dickens of a time getting the fluid to come out. After repeated attempts, it slowly started flowing and what looked looked like several blobs of gelatinous snot came out. Once those "plugs" were clear of the system, the rear brake bled normally.

I prefer a hydraulic clutch. As long as they are properly maintained by flushing every couple of years, they are much more trouble free than a purely mechanical clutch. I have memories of clutch cables from bikes of long ago breaking on me in the middle of rides. I got home by either using no clutch (tricky but can be done on light weight bikes) or jerry rigging something to the broken cable that allowed me to pull the clutch cable using by hand.

 

[dwalby]

I have memories of clutch cables from bikes of long ago breaking on me in the middle of rides.

I never had one break on me, but I think I did have to replace one because it started fraying. Don't have many data points, but I would think that its rare for the cable to just break without any warning at all, they would go bad gradually, one strand at a time and give you some advance notice of impending failure.