StooL
Registered user
Just a note to say what a difference fiddling with the TPS has made. After reading loads of threads in an effort to find a potential cause for my holed piston a few weeks ago, I decided to have a bash at setting my TPS thingymajig today. I had read that it should be set at between 0.37 and 0.4 volts. When I checked its current setting it read 0.34. After a slight (I do mean slight) adjustment I got the voltmeter to read 0.377. What a transformation! The bike now idles much much smoother. I didn't really think it was bad before but this has made a real difference. So anybody with an 1150GS that hasn't done this should do a quick search for the procedure on this site and get it done.
For all you folks that saw the hole in my piston, I still haven't found a definitive cause. The bike has been Dyno'd and aint running weak. I've changed the injector for a bit of peace of mind, checked the timing (ok), balanced the throttle bodies (weren't far out as it happened) and now done the TPS. I've also used one of those spark plug things that you can see through to see the colour to check if the cylinder that holed the piston was showing anything different from the other and they were both the same. The guy at the Dyno place reckoned the bike hadn't been detonating (pinking) as he had raced boxers before, had seen pistons that had done this and mine was different. I guess I may never know (lets hope so).
Although I now have a bike that runs pretty smooth when idling I am wondering if it is normal for these beasts to miss a beat every few seconds? "miss a beat" is the best way I can describe it. I guess its a slight misfire really. Whatever it is, my timing test confirmed that both cylinders did it.
Apologies for the ramble, I've had a few too many!
For all you folks that saw the hole in my piston, I still haven't found a definitive cause. The bike has been Dyno'd and aint running weak. I've changed the injector for a bit of peace of mind, checked the timing (ok), balanced the throttle bodies (weren't far out as it happened) and now done the TPS. I've also used one of those spark plug things that you can see through to see the colour to check if the cylinder that holed the piston was showing anything different from the other and they were both the same. The guy at the Dyno place reckoned the bike hadn't been detonating (pinking) as he had raced boxers before, had seen pistons that had done this and mine was different. I guess I may never know (lets hope so).
Although I now have a bike that runs pretty smooth when idling I am wondering if it is normal for these beasts to miss a beat every few seconds? "miss a beat" is the best way I can describe it. I guess its a slight misfire really. Whatever it is, my timing test confirmed that both cylinders did it.
Apologies for the ramble, I've had a few too many!