Rock solid stage II engine is the best in my opinion. If not that a ZBOX
Rock Solid Stage 2 kits are the best "off the shelf" kit you can buy.
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70cc HP Stage 2 Engine: Dellorto type flat slide racing carburettor, Accelerator cable to suite, MSD terminal, lead & boot, Billett Aluminium Performance cylinder head, All bolts are replaced using high tensile Allen key type, Loctite 243 thread locker, Inlet manifold porting, Exhaust porting & exhaust modifications, Carburettor idle screw adjusted, Carburettor fitted to manifold, Clutch adjusted to ensure right setting, Individually stamped identification with engine builder & numbered for ID.
Engine kit: comes complete with
* 415 chain
* Penrite running in oil 200ml
* Chain clip
* Clutch cable
* Aluminium clutch handle with clutch locking pin
* Throttle cable
* Twist grip throttle mechanism with kill switch
* 200ml running in oil
* CDI ignition box
* MSD 8.5mm lead
* MSD 90 degree boot
* MSD triple insulated terminal
* NGK spark plug
* Roller bearing chain tensioner (chrome plate)
* Sprocket wheel installation kit with high tensile Allen key bolts & Nylon lock nut bolts
* Chrome plate 44 tooth rear wheel sprocket
* Silver 2lt fuel tank
* Kartech fuel line
* Fuel pet cock
* Fuel filter with magnetic disk
* Engine mounting brackets including high tensile Allen key bolts & Nylon lock nut bolts
* Dellorto type flat slide carburettor & round air filter
* Y ties with stainless steel locking pins
* Electrical scotch clips
* Wiring crimp connectors
* Chrome plate exhaust
* Exhaust gasket 3mm Graph Foil
* CNC cut 1.5mm Inlet gasket
* Exhaust mounting bracket
* Large round tube engine adaptor
* Silver chain guard
* Screw tool
* Comprehensive fitting instructions
I have a rock solid engine i bought in 2009.... Runs great
put many more k's (miles) on it than i know of going to class and back.