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Discussion Starter · #1 ·
All,

I had my 2018 Dragster RR out this morning, and got stuck in a nasty stop and go traffic situation. This was for maybe ten minutes, then made it through. After a minute of riding free, my bike threw a "malfunction clutch switch" error code, and the quick shifter stopped working. Normal clutch and gearing was fine. I rode on. After about ten minutes, the error code cleared itself, and QS was normal for the remaining 30 miles or so.

I am guessing the stop and go overheated some clutch unit? Any thoughts? Should I look for some loose plug or nut on the QS? I will ride again this weekend and see if the error reappears.

Oh and wow my clutch hand was at its limit. I hate this type of traffic: tedious, dangerous and no fun. The Dragster likes to GO.
 

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Hello.
Ok this situation happens to me all the time, with my B3 800 2017.
If I use the clutch for much time, the bike indicate malfunction, ámbar light turns on and malfunction clutch switch appears. Quick shift stops working. The only think different from you, is that I need to turn off the bike for some more minutes, for the malfunction clear and then Quick Shifter starts working again.
Another thing that happens when this problem affects my bike, is that I cannot start the bike in first gear with the clutch pressed. It’s like the bike don’t recognize that I’m pressing the clutch. When I asked the dealer about this, they told me that I needed to adjust the pressure sensor(it’s near the front sprocket). I did this and woalaa, problem solved…. Till the next time that I got into traffic and malfunction hits again. I have been told by @Antony Ciano that some of these pressure switches are know to fail. If this keeps happening to you, you can either adjust the pressure switch, bay pass it with a mechanical switch, or change the switch with a new one.
I’m about to try with the last one, but still have to do a lot of tasks to my 44.000 km B3 800 :B
 

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Discussion Starter · #3 ·
Hello.
Ok this situation happens to me all the time, with my B3 800 2017.
If I use the clutch for much time, the bike indicate malfunction, ámbar light turns on and malfunction clutch switch appears. Quick shift stops working. The only think different from you, is that I need to turn off the bike for some more minutes, for the malfunction clear and then Quick Shifter starts working again.
Another thing that happens when this problem affects my bike, is that I cannot start the bike in first gear with the clutch pressed. It’s like the bike don’t recognize that I’m pressing the clutch. When I asked the dealer about this, they told me that I needed to adjust the pressure sensor(it’s near the front sprocket). I did this and woalaa, problem solved…. Till the next time that I got into traffic and malfunction hits again. I have been told by @Antony Ciano that some of these pressure switches are know to fail. If this keeps happening to you, you can either adjust the pressure switch, bay pass it with a mechanical switch, or change the switch with a new one.
I’m about to try with the last one, but still have to do a lot of tasks to my 44.000 km B3 800 :B

Much thanks! This is the first time I have had this problem. My bike is about 7500 miles. The stop and go I experienced was pretty severe, very unusual. I would have pulled over and stopped, but there was no place to go, jammed traffic, and dangerous situation.

If the problem keeps happening, I will talk to my mechanic.
 

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Sounds like the clutch fluid got a bit hot and boiled a bubble into the clutch switch...which then migrated out and up to the reservoir. Clutch master cylinder is subject to engine heat.
You do have a hydraulic clutch and clutch switch, right?
Maybe a good idea to flush and refill with fresh fluid.
 
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Discussion Starter · #5 ·
Sounds like the clutch fluid got a bit hot and boiled a bubble into the clutch switch...which then migrated out and up to the reservoir. Clutch master cylinder is subject to engine heat.
You do have a hydraulic clutch and clutch switch, right?
Maybe a good idea to flush and refill with fresh fluid.
Makes sense given the event history. Yes hydraulic clutch. Is there a bleeder nipple like brakes? Do I use brake fluid or something else? The stop and go was extreme. I would have pulled off the road, but there was no escape, I was trapped. Very dangerous riding situation.
 

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Discussion Starter · #7 ·
Dot 4 fluid and yes, there is a bleed nipple on the Clutch Slave.
SS,

I took my Dragster out this morning on a fairly short ride. Everything worked fine until the last mile, then the "clutch switch" error popped up again, and QS stopped. After parking, I keyed the switch off and on and the error went away, and bike said OK.

Anyway, seems that a clutch fluid bleed may help? I have the tools. May I ask where the bleed nipple is located on the clutch slave?

If a bleed does not help, I will take the bike into Brian K. I am needing a new rear tire anyway. Bike is about 7600 miles, it is counting down to a service. Is it time for valve adjustment too?

grazie,
 

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Old Wing Nut
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Check valves at 7500 miles, adjust if needed.
Here's the pic from the parts catalog of the clutch slave cylinder on the left side of the engine with the bleed nipple highlighted:
Gesture Font Art Circle Drawing
 

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Discussion Starter · #9 ·
Check valves at 7500 miles, adjust if needed.
Here's the pic from the parts catalog of the clutch slave cylinder on the left side of the engine with the bleed nipple highlighted:
View attachment 494712
Ah, found it, thanks! Looks like I will do a major maintenance on the Dragster when I return from the UK. I will see if a clutch bleed, done myself, makes a difference. A bubble could upset the system, and I bet the last bleed was 2 years ago? Not sure. Grazie!
 
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maybe start with the easy checks - like unplugging / contact cleaning / plugging in the clutch lever position switch or checking if the clutch lever actuates the switch correctly?
 

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Old Wing Nut
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maybe start with the easy checks - like unplugging / contact cleaning / plugging in the clutch lever position switch or checking if the clutch lever actuates the switch correctly?
It is a hydraulic switch on the slave cylinder on his bike.

Flush fresh Dot 4 fluid through the system until you see nice clear new fluid coming out at the bleed valve.
 
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oops - my bad.

At what model year did the clutch go hydraulic? 2016? My 2015 800rr is still old school.
 

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Old Wing Nut
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Different 3 cylinder models have different clutch systems. Some cable, some hydraulic.
 
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maybe start with the easy checks - like unplugging / contact cleaning / plugging in the clutch lever position switch or checking if the clutch lever actuates the switch correctly?
He can test with a multi tester, the continuity in the conector of the sensor. At least in my bike it’s easily reachable. Will take some pictures at home later .
 

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This happened on mine in first 1500 miles.
It cleared itself at first but gradually got worse to the point of not clearing.
Dealer replaced the switch under warranty - don't know if that suggests your problem needs more than just a bleed of the system? Worth a try tho.
 

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Old Wing Nut
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The switch is a simple single pole/single throw pressure operated switch...just like an oil pressure sensor. Actually, that is what it is.
I suspect a replacement (if needed) could be found at an auto parts store.
 
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Here's info on the problem and the switch.

 

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Discussion Starter · #19 ·
I took my Dragster out this morning on a 30 mile ride, hot TEXAS weather, and plenty of stop and go. The clutch switch error did not happen and the quick shifter was normal. I did have one minor "shudder" during clutch release from stopped and in first gear. The shudder is rare but does happen. Anyway on Saturday the bike is going into Brian K. for a full 7500 maintenance, I will let him sort it out. Also getting a new rear tire as it is fairly blocked due to our straight, flat roads.
 

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Dear Lucydad,

"Bike is about 7600 miles, it is counting down to a service. Is it time for valve adjustment too?"

It is too soon for valve adjustment yet, if you red lined it 85% of your ride then do it.

Ride on!
 
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