2004 R1150RT (Twin Spark - 6 Speed) Clutch Slip Diagnosis

[venturer434]

Hello forum, 

 

I require your valuable inputs on what I faced today related to my bikes clutch..so that I can diagnose the issue

 

Symptom: 

On a ride today on my 2004 R1150RT (Twin Spark 6 Speed) (50,000 Miles on ODO)

- I experienced a clutch slippage when I shifted from 5th to 6th gear.. the RPM increased to about 5500 and then it dropped to 4000 .. ( A few thoughts went to my mind, first was the dreaded spline failure , second was I thought I might have missed a gear shift and opened the throttle inadvertently) .

- I downshifted to 5th gear and kept the RPM at about 4500 and when there was no traffic on the freeway .. I shifted to 6th .. had no issues..bike was normal

- I had to shift back to 5th again due to traffic and after a few miles.. tried to shift it to 6th and I noticed a slippage  where RPM increased to about 4800 and settled down..(this time I ensured the gear shift and throttle opening were positive) 

- I shifted back to 5th and toggled between 5th and 4th due to traffic and headed home.. Had no issues coming to full stop and going thourgh all the gears from 1 to 5. I also varied the load on the bike and it seems to do fine..

- Prior to all the above .. today I was caught in heavy traffic for about 2 miles / 20 minutes with very slow speeds requiring constant clutch inputs to engage / disengage.. I then took an exit as I was worried the exhaust headers may damage the fairing ..and found another route

- The clutch lever feel before the ride and after the ride feel the same.. no changes to this 

 

History:

- When the bike was purchased it had about 40,000 miles. No prior history of any clutch replacement etc...

- Since I have owned it, I always used 6th gear when I was above 75-80 miles an hour where the engine RPM is above 4200.. 

- Majority of the 10,000 miles I have put are always on the free way. Never rode in very heavy traffic with constant clutch inputs. 

- The last two years the bike was in a storage unit as I was transitiong to western canada. ( The speeds are a bit low here in western canada compared to Texas, hence most of the time I am in 5th gear to avoid getting a speeding ticket) 

- No spline lubing of any sort  has been done from my end.. Clutch and brake fluids have been flushed 1-1.5 years diligently..

 

[Jim Moore]

That sounds like a slipping clutch. They normally start slipping in higher gears at mid-to-high rpm. If you roll the throttle wide open in 5th or 6th you will get slip if there is a problem.

 

On a six-speed the most likely cause is a bad slave cylinder. One quick check is to take the lid off the clutch master cylinder on the left handlebar. If it's discolored that's a good indication of a bad slave. If it's not the slave the three other likely culprits are the rear main engine seal, the transmission input seal, and the seal at the back of the tranny where the pushrod exits.

 

In any event you need to remove the tranny to figure it out and fix it. That's a big job, but eminently doable for a DIY guy with a stout heart and a refrigerator full of beer.

[dirtrider]

8 hours ago, venturer434 said:

Hello forum, 

 

I require your valuable inputs on what I faced today related to my bikes clutch..so that I can diagnose the issue

 

Symptom: 

On a ride today on my 2004 R1150RT (Twin Spark 6 Speed) (50,000 Miles on ODO)

- I experienced a clutch slippage when I shifted from 5th to 6th gear.. the RPM increased to about 5500 and then it dropped to 4000 .. ( A few thoughts went to my mind, first was the dreaded spline failure , second was I thought I might have missed a gear shift and opened the throttle inadvertently) .

- I downshifted to 5th gear and kept the RPM at about 4500 and when there was no traffic on the freeway .. I shifted to 6th .. had no issues..bike was normal

- I had to shift back to 5th again due to traffic and after a few miles.. tried to shift it to 6th and I noticed a slippage  where RPM increased to about 4800 and settled down..(this time I ensured the gear shift and throttle opening were positive) 

- I shifted back to 5th and toggled between 5th and 4th due to traffic and headed home.. Had no issues coming to full stop and going thourgh all the gears from 1 to 5. I also varied the load on the bike and it seems to do fine..

- Prior to all the above .. today I was caught in heavy traffic for about 2 miles / 20 minutes with very slow speeds requiring constant clutch inputs to engage / disengage.. I then took an exit as I was worried the exhaust headers may damage the fairing ..and found another route

- The clutch lever feel before the ride and after the ride feel the same.. no changes to this 

 

History:

- When the bike was purchased it had about 40,000 miles. No prior history of any clutch replacement etc...

- Since I have owned it, I always used 6th gear when I was above 75-80 miles an hour where the engine RPM is above 4200.. 

- Majority of the 10,000 miles I have put are always on the free way. Never rode in very heavy traffic with constant clutch inputs. 

- The last two years the bike was in a storage unit as I was transitiong to western canada. ( The speeds are a bit low here in western canada compared to Texas, hence most of the time I am in 5th gear to avoid getting a speeding ticket) 

- No spline lubing of any sort  has been done from my end.. Clutch and brake fluids have been flushed 1-1.5 years diligently..

 

Morning venturer434

 

That does sound a lot like clutch slippage. 

 

With the motorcycle on level ground try a somewhat aggressive 2nd gear launch, if you have clutch slippage then that will usually show it quickly.  (if it starts slipping abort so as to not abuse your clutch anymore than necessary)

 

If it's a master cylinder leakage issue you can sometimes remove the starter, hold the clutch lever in with a zip tie then try cleaning the clutch disk with brake clean sprayed into (onto) the clutch disk through the starter hole.

 

Obviously also replace the salve cylinder. 

 

 

[fatbob]

Clutch replacement underway on my 2003 in 2018.   Big job, but do-able.    You can replace a lot of seals while in there.  Mine was a slave leak problem.