seriously? ok, here goes...
on the GT5 66 Skyhawk's:
the headstuds are never bottomed out, and when you do it yourself, the nuts no longer fit on them. instead of using multiple washers and crappy acorn nuts, the correct length studs should be used, bottomed out, one flat washer and one lock washer each, and hex nuts.
the cast aluminum mounting brackets (not the mount itself, but the C shaped bracket) is junk. tighten them down too much and they snap in half. and by "too much" i mean, tight as they should be.
the fins on the jugs are horrible. besides being bent on every engine i've had, the left over casting flash makes a sharp, ugly edge on them.
the inside edges of the ports are always rough and need to be cleaned up before chroming, as grinding them smooth can mess up the chrome.
as for the rest of the kit, the CNS carbs are too big and they don't seal properly. that's the real problem with them. it's not that the carb itself is junk, it's that it's too much carb for the engine, and they always have airleaks, due to the cheap plastic seal and the shoddy bent-over steel intake, which usually isn't perfectly round after being cut, bent, and re-welded.
i understand the need for EPA compliance, but either a different manufacturer should be found to supply the carbs, or a smaller CNS should be used.
the carb is the single most cause of dis-satisfaction with these motors. search "CNS" on this forum and it'll turn up a million posts about people who hate them and can't make them work. it's no use having an EPA compliant carb when 90% of the people order an aftermarket NT and throw away the CNS. and the cable operated choke with the cheap click shifter lever is a joke, and it's ugly.
also, matching the ports for the intake and exhaust flanges would be nice, too.
on the exhaust pipes, on all the ones i've built to run with the stock exhaust, the larger "catalytic converter" breaks apart and tries to blow out of the pipe.
and get rid of the acorn nuts on everything, for that matter. 90% of the time they bottom out before they get tight.
there are multitudes of other problems, but most of these are the most common. other problems i've had was a head not being milled properly so there was a gap between the head and the jug at the headstuds. meaning, there was a taller, circular lip around the combustion chamber, so even though it mated to the jug, there was a gap at the corners where the studs were. when you tighten it down, it wants to bow out inbetween the studs.
and on the GT5-A superhawk, the heads need to be twice the thickness. every single one of them has blown headgaskets, usually after less than a day of riding, and they're are totally useless. i've gone up to 3 head gaskets to decrease the compression, and all it did was make me run out of head gaskets.
the simplest solution, is to place the yaun dong factory directly over a faultline or a volcano, then pray to whatever yokia goblin that lives there to swallow the factory up.
then, go to the starfire factory with 30 grand (or whatever it costs these days) and get the engines made there. i've never had a problem with a GT4.
does it get everything out?
