Someone on Orkut’s SV community posted yesterday, inquiring about the front spark plug drain hole. It prompted me to finally go take a picture of the one on my bike, as this hole is a well-kept secret that can save a lot of headaches.
If you own an SV(S), go out and find this drain hole. It’s a small hole about halfway down the righthand side of the front cylinder.
This drain hole ostensibly drains the front sparkplug well. Unfortunately, the SVs’ front sparkplug seals have a tendency to leak water in heavy rain, which means that dirt and grime can get down into the well and clog up the drain hole. Water then pools up in the sparkplug well, eventually “drowning” the sparkplug and causing misfires (or a complete lack of firing) in the front cylinder.
So: if your SV ever acts like total shit in the rain (or just after a washing/rainstorm), pull off the front sparkplug boot and re-seal it. Then, shove a pipe cleaner up that drain hole and clear it out. Nine times out of ten, this will solve your wacky engine behavior.