From the factory the motor is jetted rich to be on the safe side. Assuming that there is still good compression... have the rings been replaced? The easiest solution would be to adjust the carburetor leaner. I would adjust the needle jet (the slider) to the 4th or 5th ring on the end of the needle jet. If this isn't enough, depending on your elevation you many need to put smaller main and pilot jets in the carb. I would go one size at a time letting the engine run at normal temperature before trying it again.
Jeff
park it in the garage until you work out what problem you have
If a Honda Civic is over revving than there may be a problem with the ECU. One of the functions of the ECU is to prevent the engine from over revving.
i personally am experiencing this problem right now.... the car was diagnosed as having a problem with the engine coolant sensor- i ordered and picked up the part and am trying to replace it now
You may not have enough fluid in your coolant system ... or ... your thermostat may be the problem opening up too much.
Fault with the clutch probably.
Highly-inflated ego.
the transmission is slipping
check your carborator cause those are known to go bad on honda's and cause that problem and if its not that then its your vacuum line
because someone probably turned the engine on
Most likely revving due to a dirty/clogged air filter.
worn belt or your clutches need to be rebuilt
It will if you are free reving the engine with out it being in gear. If you are driving it hard down the road and it is kicking in then you may need to have the engine scanned with an OBDII engine scanner and make sure you don't have a problem in the system.