carb second level of H*ll

I fell over gashed my head open on a hood edge. Thanks on the info for petcock I did look threw that.

 

Droped the carbs off to yamaha shop today they said the jets are over sized from cleaning and the carbs were not squared up. hope filly tomorow they will be done

 

Sputtering while steady throttle but otherwise runs good no issues with leaking or acceleration or de acceleration waiting on wheel finally got most the demons exercised just few left

 

Could that be simply due to needing a running sync I wonder?

 

Ok got the bike back again runs good not great still sputtering on steady running speed. I put air fuel gauge on it and its running rich. The air fuel screws are set at turn and a half out. The plugs on 2 3 and 4 are all looking OK or maby a little lean number one tho is black as coal with some soot on it after 46 miles. Carbs were sync and adjusted not sure if I just need new Carb or what? They were cleaned and the idle circuit is clean also

 

ONCE THE VALVE CLEARANCES ARE IN SPEC, it sure could.

 

Had them checked the clearance is right on its only one cylinder that's not running right

 

OK, so if the valves are in spec, the float levels accurately wet-set, the carbs as bench sync'ed as they can be; then the next step is...

your running vacuum sync. The carbs have to be sync'ed to your motor, that isn't something that can be done with them off the bike. And you can't get a good vac sync with out-of-spec valves.

If this is a YICS motor, the YICS will need to be blocked for the running sync.

Quick question: has anyone done a compression test on this motor recently? You don't want to be fighting a battle you can't win.

 

Had the carbs sync while on bike running don't know if they blocked yics off was not there did run Much better than when I drooped it off but only first 20 or so miles. Got it back home and pulled the plugs found that #1 was black and then checked what carbs set at and the screw by the choke valve is out one and a half turns bowls are running clean fresh fuel in it. Will check compression tonight bit it was all with in a few pounds of each other at first check only 100 maby 200 miles on it now still fighting Carb issues

 

You should consider acquiring a ColorTune Plug.

The ColorTune Plug will allow you to very rapidly find an IDEAL Idle Mixture.
Having the Bike tuned to its optimal Mixture to IDLE, like a sewing machine, will bring you very close to getting "Dialed-in".

With the Air Screws set to deliver a precision stoichiometric Idle Mixture; their additional adjustment to the state of being Fine Tuned is but a Tweak or two from right-on-the-money.

Attention to details.
Don't compromise anything during this critical phase of preparing for peak performance.
Make it all copacetic!

 

Rick - I'm reaching for the dictionary again!

 

What will a color tune plug do? Not sure to there use I always used an air fuel meter to tune with ( autos) have a set up for tuning bikes with this now so I can get real time air fuel on it. The screws you are referring to are air screws by choke? They are adjusting only at idle? The low to mid air fuel is set by the needle correct? Top end and high mid is off the jet size witch is stock here only mod to bike is a uni filter

 

Well another dead end going to look for new Carb and coil maby that will work

 

120 psi cold dry check all across one number 3 is at 119 lol good spark across also idlse good valves all at spec got to be the #1 Carb is messed up any clues idles good but fouls under load steady throttle

 

Took Carb #1 apart top half cleaner run threw all air jet ports blew it out put back together same thing run it for five minutes fouls out #1 plug. The needle seems to stick when pushed up on the Carb tearing another apart to see if changing from one Carb to another will change this or are these not interchange with one to another?

 

One and two cylinder are at different hightails on the needle in the plunger swapping them now hope this works

 

Found my problem or so I think one of the needles are longer than the rest can not find a mention of adjustment on these. Is the long one wrong for the carb or are they adjustibule ? What is the hight to set at? and how ?

 

HITACHI VACUUM DIAPHRAM AND PISTON ASSEMBLY:

fs5) OEM Hitachi HSC32 series carbs VACUUM DIAPHRAM AND PISTON ASSEMBLY, the slide piston with the non-detachable rubber vacuum diaphram seal. Although it is possible to repair TINY pin-holes that occur in original diaphrams, anything greater than that will require replacement, as these diaphram are under a lot of pressure and stress and the continued flexing of the rubber will eventually lead to failure. Fits all XJ650 (except Turbo) models, and all XJ750 models.

HCP69 OEM Hitachi carb VACUUM DIAPHRAM AND PISTON ASSEMBLY, brand new, each:
$ 244.95

HCP69SET4 OEM Hitachi carb VACUUM DIAPHRAM AND PISTON ASSEMBLIES, set of 4:
$ 929.95


Sombody please tell me that the needle at the end of this thing is adjustabule...

 

not really but they are removable there is a plastic hex head inside the piston that needs to be turned a little to release it. there is a spring so be careful things don't go flying. there should be a number cast into the plastic end of the needle to let you know what you have and need.