Honda GX390 Parts for Predator 420cc

M

MustangMechanic

New Member
#1
#1
Hey guys, I am going to use an electric start, big block, motor for my next project- a kart this time. Anyways I want to save a few bucks and get the Predator 420 motor. BUT No one makes heavy mods for it. I asked some folks at OldMiniBikes warehouse, as they have GX390 parts and 420 Parts listed together- Do all GX390 parts work on a 420? I want to remove Governor, billet rod, billet flywheel, maybe head mods, etc. I know the gx200 and predator 212 were all a little different, but from what ive heard the big blocks are exact copy's.
Can someone confirm? And if no- where can I find the cheapest Gx390 w/ Electric start?
 
trinik7597

trinik7597

Active Member
#2
#2
Bore is obviously different on the 420cc so piston will not work Honda is 88mm and 420 is 92mm I believe.. you would have to know if the rod journals are the same to know if the rod will work but I am pretty sure rods and cams interchange as well as springs and flywheel .. but I don't think they have a billet wheel with a ring gear for electric start
 
M

MustangMechanic

New Member
#4
#4
Well obviously Bore, but I wonder if anyone has both these motors available to test with. I really need a billet rod. OldMiniBikes Warehouse sells a Billet with starter gear. Cams will work I know, because they asked the Mfg. This karts gonna be pretty cool and unique. Annnnd expensive...
3 speed trans with Reverse home made. Im using 2 jackshafts, and two double hubs as selectors. Its complicated but its going to use chain and sprockets submerged in gear oil. ANYWAYS- I'll leave this open maybe someone has some experience.
 
You must log in or register to reply here.
Top