My bike is a 2010 GSA TC. I had the same occasional intermittent stalling problem when downshifting. Only happens about once a day if at all, but also a very occasional stutter when I try to blip the throttle in neutral, and always only when bike is well and truely warmed up.
This stalling problem is well documented throughout this site and I've taken advice from all the available posts.
A year ago the bike had cat removed then was re-mapped by a guy in Dublin....( Hilltop was too far from Northern Ireland).
After the remap I fitted fancy iridium plugs.
Remap went a bit wrong.... bike began running mega rich (i.e. mpg dropped to about 32 ) I was committed to a big Euro trip and it was about 3500 miles before I got the bike back onto the rolling road for the fuelling to be sorted. Now back up at 50+ mpg and feels mega fast and well sorted.
BUT the occassional stall was still an annoying trait with the bike.
Oil change and new air filter a couple of weeks ago, read here that the fault may be a possible failing coil stick, so I borrowed a 2013 TC and tested mine with it's coil sticks over a couple of days. No stall, but still the occassional stutter on blipping the throttle. I'm convinced my coils are ok and the problem is something else.
Not wanting to shell out for 2 lambda probes, otherwise known as oxygen sensors, but I'm convinced the mega rich fuelling for 3500 miles has fouled something up in the bike, I order a pair of 2nd hand ones from an 8K mile bike. Also decide to bin the new fancy plugs and go back to a new standard set spark plugs.
All fitted last night and bike running well..... but it always has done, just an occasional stall or stutter was all I ever experienced. It will be later in the week before I get to go for a long run on the bike and might take a few runs to be sure if the problem is away. I also hear the stepper motors (?) might need reset with a GS-911 and throttle sync to finish it all off, so I'm gonna chase that up this week too. Not sure what stepper motors are, but will get it done non the less.
Anyway, I was a bit shocked when I removed the lambda probes.... both are sooted near the thread, consistent with a bike running too rich I assume???
But the lower end of both are a strange red colour, almost like the colour of that red oxide paint. (left is the old probe and right is the replacement 8K mile probe)
The only other thing I have done with the bike is as follows..... knowing the TC is designed to run on 98 RON super unleaded, which is not available in Northern Ireland, on about 50% of the fills I've added 97 RON and on the others, I have added 95 RON plus the recommended amount of Millers Petrol Power Eco Max, which claims to increase power & mpg, reduce emissions,cleans injectors & adds up to 2 octane numbers.... the last one being my reason for adding the stuff. I don't really think a few mills of this is turning the probes red
I'm an amateur tinkerer who gets satisfaction fom having a go myself, but has no technical knowledge. What's the thoughts on the discolouration of the probes?
This stalling problem is well documented throughout this site and I've taken advice from all the available posts.
A year ago the bike had cat removed then was re-mapped by a guy in Dublin....( Hilltop was too far from Northern Ireland).
After the remap I fitted fancy iridium plugs.
Remap went a bit wrong.... bike began running mega rich (i.e. mpg dropped to about 32 ) I was committed to a big Euro trip and it was about 3500 miles before I got the bike back onto the rolling road for the fuelling to be sorted. Now back up at 50+ mpg and feels mega fast and well sorted.
BUT the occassional stall was still an annoying trait with the bike.
Oil change and new air filter a couple of weeks ago, read here that the fault may be a possible failing coil stick, so I borrowed a 2013 TC and tested mine with it's coil sticks over a couple of days. No stall, but still the occassional stutter on blipping the throttle. I'm convinced my coils are ok and the problem is something else.
Not wanting to shell out for 2 lambda probes, otherwise known as oxygen sensors, but I'm convinced the mega rich fuelling for 3500 miles has fouled something up in the bike, I order a pair of 2nd hand ones from an 8K mile bike. Also decide to bin the new fancy plugs and go back to a new standard set spark plugs.
All fitted last night and bike running well..... but it always has done, just an occasional stall or stutter was all I ever experienced. It will be later in the week before I get to go for a long run on the bike and might take a few runs to be sure if the problem is away. I also hear the stepper motors (?) might need reset with a GS-911 and throttle sync to finish it all off, so I'm gonna chase that up this week too. Not sure what stepper motors are, but will get it done non the less.
Anyway, I was a bit shocked when I removed the lambda probes.... both are sooted near the thread, consistent with a bike running too rich I assume???
But the lower end of both are a strange red colour, almost like the colour of that red oxide paint. (left is the old probe and right is the replacement 8K mile probe)
The only other thing I have done with the bike is as follows..... knowing the TC is designed to run on 98 RON super unleaded, which is not available in Northern Ireland, on about 50% of the fills I've added 97 RON and on the others, I have added 95 RON plus the recommended amount of Millers Petrol Power Eco Max, which claims to increase power & mpg, reduce emissions,cleans injectors & adds up to 2 octane numbers.... the last one being my reason for adding the stuff. I don't really think a few mills of this is turning the probes red
I'm an amateur tinkerer who gets satisfaction fom having a go myself, but has no technical knowledge. What's the thoughts on the discolouration of the probes?
I had a discussion with the guru Dr Fark earlier.... he explained the stepper motor thing to me, but my goldfish retention of information syndrome has kicked in and I still have no idea what they do, how to disconnect them or ........... why I am typing this. 
