Hi, my bike has started to throw some oil from around where the tacho cable exits the top of the engine - I've noticed it starting to drip (and spray a bit) on the horizontal part of the frame just under the cable. Is this normal? If not, is it bad? Should I try tightening the tacho cable? Any ideas would be greatly appreciated...

try tighting it back up and teflon "plumbers" tape will fix it if the tighting thing dosn't work

If it is leaking around the threads the teflon tape will work great. Now if it is leaking around the black sleeve that is on the cable you would need to replace the black rubber seals that are located inside the metal thinggy the tach cable connects to mounted on your engine. I had to replace one of the two seals but figured I would just do them both. Cost me about ten bucks for both seals at my local zuki dealer.
Hope this help......

Ditto what Jeppy said.  I had a very very small leak the mechanic noticed when I initially checked my bike out.  He said it's no big deal, just needs a little rubber seal/gasket/whatever, get it done at the next oil change.

Somehow it stopped leaking tho.

Thanks, dudes!