Aprilia RS 125 will not spark! Please help

[emdell]

Hi, I've got a 99 reg Aprilia RS 125, when I bought it had a simple starter motor problem + torn throttle cable but I've since replaced both but I can't get the bugger to start at all.

I'm not getting any spark from the spark plug at all. So far the list of stuff I've replaced/tried using off a mates running RS:

Spark plugs
Ignition Coil
HT Lead
Spark Cap
Complete wiring loom (second hand in good condition)
fuses/fuse box
CDI + the black plastic box behind it (not the reg/rectifier on the side - today I noticed the reg/rectifier has a slight chip on the under side could that be a problem?)
Ignition pick up cable
Right hand switch gear - the connecter on the kill switch wire was a bit tatty so I've replaced that, but is there a way to bypass the kill switch to make sure it's still not acting up?
starter solenoid
new battery

Getting decent compression - 130 PSI

Driving me absolutely mad, I can't find the fault anywhere, took it to one garage and they said the 'engine is broken' but wouldn't specify what was broken, went to another garage who said the wiring loom needs replacing but refused to work on a second hand loom in case it had defects in it + would charge £200 for the labour.

so now what? what else could it be?

[sidewinder]

Have you changed your usual st oil for a different type? A good quality oil can make all the difference
____________________
"Nitrous is like a cheap hooker, you want to hit it but are scared of the consequences

[Matt-]

[thomp1983]

just replacing components isn't the way to go about it as your finding out. you need to get a multimeter and a wiring diagram. first check the ground path is as it should be from the battery. after that from the battery follow the power around the ignition and start circuit from the battery positive until you come to the part where power goes into something and doesn't come out, if it's a connector check it for corrosion, if it's a component of some sort google how to check that component, most bike components can be checked with a multimeter. ive just spent the last couple of hours doing this on a friends rs 125 and alot of the connectors are corroded and his is quite a bit newer than yours, there a very simple bike electrically you just need to be methodical in going over it

chris