poop.
i read this and crossed my fingers and hoped it was the case...leaky throttle shaft.
stripped carby(only ten times in two days!) removed rod, machined groove and inserted an o-ring.
moral of the story? use the lathe to make an adaptor plate to take a z50 style slide carbie
ok, my problem.
just put a huasheng onto my bike. went for the chain drive to rear sprocket style, after having tried FD too many times before with all those hassles... (a 5km hill in drizzle is almost reason to cry)
so, chain, tensioner, frame, tank.
tanks lower than carbie so i flogged a pump from an old briggsy. pressure pulse from rocker cover.
all has been good for past two weeks. not.a.problem! beauuuutiful
yesterday, ride to a friends, a fair trek. halfway, engine starts coughing, dies.
hmmm.
pulse feed for the pump had some oil in the line. drained it. remove fuel line, crank engine. pumps working fine.
attempt to start, nothing.
go full choke, starts.
choke off, dies.
grrr, i say. ive had an issue with the carbie before with the engine on a stand. apparantly fixed.
so, rode home, full choke, splutter splutter, not terribly great fuel economy on that trip...
stripped carbie, cleaned thoroughly, every **** orifice, even using ultra fine wire to get into the two idle ports visible just as you crack the throttle. everything. compressed air, a soak in acetone, carbie cleaner, more probing with the wire, more air, ad nauseum. blindfolded, i could dismantle n reassemble one of these with my pinky toes now.
it is not;
fuel pump. float bowl is always full. problems still there when i use a normal gravity feed with no pump.
dirty fuel. i siphoned some different brand petrol from the mothers van, and flushed system. no use. no water, no contamination, etc.
plug. changed plug. twice.
main jet. approx 0,8mm. every lil hole is clear, emulsion tube holes, blah blah.
leaking gaskets. gasket goo, leak tests, you name it, ive tried it.
the lil plastic cap under the idle screw, pulled that, replaced o-rings, they tend to get chewed. nope.
valve clearance. gapped to 0.05.
my pulse feed. i considered it might be the crank breather acting as a venturi the way its set up on the air cleaner, causing pump not to pump.
blocked off my pulse feed. no difference. and it couldnt have been this anyway, as the pump is working...
float height. fixed. un adjustable. plastic molding.
nothing has worked.
there is no killswitch or wires to be leading me off track.
all else i can think of is my coil is starting to burn out, which would be annoying, but possibly not as annoying as not having any idea whatsoever!
also have no coil to try. at least, one that matches the crank radius.
its not a terribly complicated carby. so why the problems? grrrr.
anyway. my few last tricks are to drill the jet(which i see as being sorta pointless cus its been fine up til now),replace carbie, or modify a brushcutter coil...
grrr!
any ideas ppl?
it sounds like it is starving. and the earlier problem was when i blocked the overflow. that had much the same effect... it is not blocked this time!