My aprilia rs 125 2000 model won't come out of gear the engine starts when you hold the clutch in but the gear lever won't budge, has anyone got any ideas of what could be the problem???

SOURCE: de-restrict an aprilia rs 125

You shouldn't have to restrictions only happen on faster bikes 600cc onwards but if you talking about the inabilty to push your revs to the very max, I wouldn't do this unless you know what you doing, and by you asking this question, you don't know what u doing, this rev restriction is set in place for safety of your engine, rather than restricting speed.,,,

SOURCE: Clutch cable's change

If this is the same as the RS125 cable i changed then the cable goes into the clutch cover engine casing yes? You do not have to take the whole engine apart you need to disconnect the cable from the lever and then you will have to take the clutch cover off. before you do this you will need to lean the bike on its side as you will lose the gearbox oil otherwise. plus the cluch will fall out as it is held in with dowels and not bolted (stupid design) once you have the cover off then you can disconnect the cable. if your gentle when taking the cover off then u will not have to replace the gasket however this rarely happens you will deffianly need to get a new gasket about 4quid. reconnect your new cable and then put the gasket on and be carefull wen putting the casing back on the engine making sure you do not damage the new gasket.
hope this helps.

SOURCE: my aprilia rs 125 is ok out of gear but when u put

Mate I had this problem, it was the compression, had to get new piston and rings. good luck.