Crankshaft Oil Seal for Honda GX390
Crankshaft oil seal fits Honda GX340, GX390, 420cc and 460cc engines. Use this seal on both the PTO or Flywheel side. Engine requires two per engine so order a quantity of two per engine.
Bronze Valve Guide, 6.5mm Honda GX390
Bullfrog Performance Products bronze valve guide set will fit the Honda GX340, GX390 and many other big block clone engines with factory diameter valve stem size of 6.5mm. Our bronze valve guide will outperform in longevity and performance over the factory steel guide. Has closer to the same heat expansion rate as aluminum head for a more stabil valvetrain operation. These are sold per valve guide so order two for replacing guides in head intake and exhaust!
Air Filter, Angled 4" Long x 2 7/16" ID
Small engine racing air filter for use in many applications including go karts, mini bikes and many other off road applications.
Aftermarket air filter for the Predator 212cc, Honda GX390, Clone engines when using our air filter adapters with 2 7/16" OD. This air filter is an aftermarket version of the K&N cotton gauze design. Be sure not to forget our air filter oils and cleaners to keep your air filter performing at its best.
Dual Valve Spring Kit for Honda GX390 65 lbs
Bad Ass Minis 65 lb. dual valve spring kit for the Honda GX390 big block single cylinder racing engines. We highly recommend our 65 lb. kit when using any cams with .300" lift and higher.
96mm Head Gasket for Big Block Engine (No Oil Feed Hole)
Bad Ass Minis performance head gasket specifically designed for Bad Ass Minis big bore 95mm cylinder blocks. This head gasket fits 96mm bore big blocks and is Made In USA!. This head gasket has a 96mm bore and is .043" thick and does not have the oil feed hole made into gasket.
40mm Stainless Steel Intake Valve for Honda GX390, 460cc Big Block
Bad Ass Minis stainless steel intake valve fits Honda GX390, 460cc engines. We highly recommend this valve when using high lift aftermarket racing cams to prevent valvetrain failure.
Be sure to include our billet aluminum or titanium valve spring retainer kit with our valve.
33mm Stainless Steel Exhaust Valve for Honda GX390, 460cc Big Block
Bad Ass Minis stainless steel exhaust valve fits Honda GX390, 460cc engines. We highly recommend this valve when using high lift aftermarket racing cams to prevent valvetrain failure.
Be sure to include our billet aluminum or titanium valve spring retainer kit with our valve.
Header Kit, GX390 Mud Motor Header w/Muffler Straight
Mud Boat header kit that fits the big block Honda GX240, GX270, GX340, GX390, Predator 420cc and 460cc engines. Our header kit features 1 1/4" O.D. header tube and is TIG welded for best durability. Our header kit includes the following components:
- Straight header tube to fit mud motor specifically
- Our custom TIG welded header flange
- Screw on muffler
Header Kit, GX390 Mud Motor Header w/Muffler Angled
Mud Boat header kit that fits the big block Honda GX240, GX270, GX340, GX390, Predator 420cc and 460cc engines. Our header kit features 1 1/4" O.D. header tube and is TIG welded for best durability. Our header kit includes the following components:
- Header
- Our custom TIG welded header flange
- Screw on muffler
Crankshaft, 69mm Stroke GX390
69mm stroker crankshaft for big block 460cc engines. Can be used in Honda GX390, but you may have to mill your piston to fit the Honda GX390 block.
Billet Valve Cover, Honda GX390 Big Block w/Cooling Fins
Our billet valve cover for the big block engine features our unique integral cooling fins for additional valve spring chamber cooling. Our billet valve cover is the lightest cover on the market. You can throw away your stock valve cover gasket as our cover comes with an o-ring seal that promotes better clamping force and eliminates oil leaks. The other billet valve covers on the market do not have the machining time put into their valve cover to make them work as a bolt on piece. Our cover is taller than the factory valve cover so it will clear any roller rocker arm on the market. You will also receive our custom machined aluminum crankcase breather fittings.
Bullfrog Performance Products billet valve cover fits big block engines listed below:
- Honda GX240
- Honda GX270
- Honda GX340
- Honda GX390
- Powerhorse 414cc
- Vegas Carts 460cc
- LCT 414cc
Our big block billet valve cover will only fit the wedge style head and it will not fit the hemi heads on Predator 420cc.