Moteurs et pièces Goped

Billet delrin version is now available and is half the weight of the aluminum version. OBR power stack is compatible with most aftermarket clamp on air filters. This is a bolt on performance item that will improve power on any engine that's stock or fully modified. We spent several months developing this stack on our in-house flow bench and dyno. We've seen more power out of this design than any other stack that we have tested. Dyno graph can be found in the images. Tapered bore increases velocity through the intake tract and gives better consistency. The clamping surface has barbs to prevent the air filters from falling off under hard running. There is no boss on this stack which allows the air filter to be pushed closer to the carb for cars that have minimal air filter clearance.

These engines are built to order and will not ship within 24 hours like parts. Typical lead is about a week but that varies on how busy we are. If this is an issue please contact us prior to ordering for a current lead time. 

Complete fully modified/ported GP460 / GP470 engine for goped use. Engine comes complete with clutch, HDA-223 carb and v-stack. Exhaust is not included and we recommend a Jetpro Rhino pipe to match.Transfer bowls have been modified so that a stuffing mod is not required like a stock case to increase power. Intake tract, reed valve and transfer bowls were in-house flow tested and dyno tested to produce as much power as possible. You can expect to see a lot more torque and mid range power then a piston port GP460 or GP470. We've used high quality carbon fiber reed petals for more power and longer life then fiberglass petals. 

Porting/machining:

intake port filled and 2 boost ports added

piston lightened/reshaped w/dual windows to match boost ports

all ports resurfaced

transfer port bridge knife edged

exhaust duration advanced

exhaust port widened and flowed

Stock GP460 crankcase that was pulled from a new engine. These have not been used but will have marks from being assembled & disassembled. Bearings and seals are included and assembled as shown in picture. Minor cleaning required before use.

Complete GP460 bottom end from a new dissembled engine. Complete with bearing, seals and crankshaft. Some cases are sealed and some have been split but are brand new and unused.

Fully ported GP460 engine complete with carb and clutch.

Complete OBR reed crankcase for the GP460 and GP470 engines with vented billet clutch housing. A case reed ported top end is highly recommended. We've designed our reed case for dual boost ports. Cases come with complete with carbon fiber reed petals, nachi bearings, seals, hardware and a reed cage gaskets. Case halves need to be sealed with a quality sealant such as threebond 1211. A carb isolator is also included to prevent the case from transferring heat to the carb

Complete fully modified/ported GP460 / GP470 long block for goped use. Long blocks are complete as shown in picture with reed crankcase, crankshaft and fully modified top end. Exhaust is not included and we recommend a Jetpro Rhino pipe to match.Transfer bowls have been modified so that a stuffing mod is not required like a stock case to increase power. Intake tract, reed valve and transfer bowls were in-house flow tested and dyno tested to produce as much power as possible. You can expect to see a lot more torque and mid range power then a piston port GP460 or GP470. We've used high quality carbon fiber reed petals for more power and longer life then fiberglass petals. 

Porting/machining:

intake port filled and 2 boost ports added

piston lightened/reshaped w/dual windows to match boost ports

all ports resurfaced

transfer port bridge knife edged

exhaust duration advanced

exhaust port widened and flowed

Goped throttle linkage for use with our reed cases. Use of this linkage requires that the primmer bulb be removed. Linkage plate is supplied with mounting bolts and the throttle shaft plate/swivel to match. A throttle return spring is recommended.

Brand new GP460 crankshaft removed from an engine. Some may have cosmetic blemishes from assembly/disassembly.