HELP,, sudden problem in engin after carb installing

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khaled

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First of all I?d like to thank you all Vmax friends on the forum ,,, actually , I removed the carb out from the manifold, cleaned the four carbs and replaced the damaged rubber joints between the manifold and the V boost , and replaced the four air/fuel screws , rebuild the manifold, tuned the V Boost, then installed the carb, then started the engine, it was working perfectly , the RPM seems to be little high (1200) but very smooth for two days for not long trips , I replaced the oil, the oil filter, and then suddenly the engine went very bad like it work in three cylinders and it turned off!! I heard a ? clicking ? sound under the dummy tank cover when it went to off idle speed .
Is it because of synchronize need? I got the vacuum reading for each cylinder as following:

1= 9 inHg 2= 6 inHg 3=4= 10inHg
I know how to adjust the pressure for cylinder 1,3,4 but how to adjust the pressure of the 2nd one? And what the most proper value to be adjusted?? Need for your support.
 

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#2 is the master cylinder that is pre-set at the factory.... there is no adjustment on it. The other carbs are tuned to #2.

I would do a vacuum sync and see how that works before anything else.
 
you do have a manual or have read the procedure right? you sync the #1,2 carbs with the left side screw then the #3,4 carbs with(help me danny i forget the rear screw on right side) then the other screw is to sync the 1,2 to the 3,4 carbs....might have to go back and readjust once or twice, blip throttle inbetween screw changes..........very little turns to make big differences
 
so khaled PM'd me that he's synched up his carbs per a "how-to" that I provided him. i told him that he should bring his idle down back to 1000, but he says the adjustment knob is already as far as it will go. i wonder if the idle knob, or the throttle cables, or the choke linkage are suspicious. what do you guys think?

he went on to correct my thinking that the clicking sound was the fuel pump as i had previously thought, but rather, he explained to me that the clicking sound came from somewhere in between the airbox and handlebar. i'm thinking perhaps the ignition unit? what other elecromechanical or electronic device is in around that area?
 
but the bike still starts now or no?bad ground or batt connection would be place to start, any blown fuses? maybe it was the ign box giving up
 
OK... I tried to find out the sound of the clicking, removed the air filter, found it came directly from the Cylinder no.1 and a kind of spark observed from the top-side, that is all in the same time of unstable engin running with high idle speed (2000) with lowest idle screw setting.
I measured the again the pressure at the four cy. they all not stable goes ups and downs related to the engine speed! and any little change in any sync. screws can cause a huge rpm. WHAT CAN I DO? I'm comfusing , and I wanna mention here that all this happened after changing the oil and the oil filter,,,may it cause these things or may not.
 
you mean spark is arcing? if so check plug wires for cuts splits etc also be worth checking or chg plugs if old but sounds like plug wire issue
 
you mean spark is arcing? if so check plug wires for cuts splits etc also be worth checking or chg plugs if old but sounds like plug wire issue

+1.....that's what I was thinking a couple of posts back......the coils are up front but you usually don't hear them arcing like you do coming from the HT wires..................
 
I am seeing the sprk light inside the carb from the top side (air filter sid) syncronizing with the bombing sound from carb 1.
That beside the unstability in the engin reving as mentioned in preavious thread

I'll try to sync the carbs again and check the HT cabl and spark plug and feed back

Thanks alot guys for your supporting
 

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