[mvhbiker]

Hey, y'all a few months ago I purchased a 1994 Kawasaki ex500. It ran perfectly until recently. The bike would not crank, I replaced the starter motor which fixed the problem. But I got back from my test ride after replacing the motor and as the bike was idling it started bogging down and died while idling. When I attempted to give the bike gas the same thing would happen. I'd give it gas and then say the rpm needle was at 3000 rpms it would drop to 2000 then back up to 3000 then down to 1000 then back, and then die. That would happen rapidly, the same thing while just idling. I assumed it was a carb problem, so I have now cleaned out the carb with an ultrasonic cleaner and rebuilt it with an all balls carb rebuild kit. After putting the carb back in the bike it will not start. One important thing to note is I have never worked with carbs before so the carb is almost certainly not tuned right. I have replaced the battery and spark plugs but no luck. I've checked the fuses, plugs, and wires but they all seem to be fine. Is it possible this is still a carb issue? Thanks!

 

[yorkie]

yes of course it is. plus a number of other things you may or may not have checked. at this point your chasing ghosts.
eliminate other issues first like have you got a good spark, battery, connections, if all that checks probably it is the carbs.
it's not unknown for novices to do carbs 3 or 4 times before getting them right, TBH there is only really one way to do them complete strip down clean every part split the carbs replace the rail O rings make sure every port and orifice is clear then reassemble with new gaskets and O rings MAKE SURE YOU DO A WET TEST ON THE FLOAT LEVELS. balance the butterflies and set the mixture screws to 2 and a half turns (may need tweaking later) make sure the air filter is clean
when running set the idle to 1200 rpm. if you still have issues try spraying easy start on the carb rubbers while its running if the revs alter you have an air leak in the boots.

 

[auburn]

did you clean the fuel vent?

bpe's guide to servicing your gas cap, careful with the ball bearings

 

[bpe]

The gas cap could account for the bogging down and dying, but not so much for the RPM fluctuating up and down.

I do like seeing links to my threads 😁.

 

[ducatiman]

have now cleaned out the carb with an ultrasonic cleaner and rebuilt it with an all balls carb rebuild kit. After putting the carb back in the bike it will not start.

I'd be highly suspicious of any non-stock tuning components from a "carb kit". Note the size differences documented in my attached pic.
Also...within your efforts have you analyzed the petcock function? Possibly something amiss there as well.

 

[grasscutter]

Everything from all balls is trash. Period.

Find the appropriate parts, OEM. It’s not more expensive, your dealer almost always has what you need or go to partzilla online.

 

[Custom Carb Service]

within my service, unless destroyed....restoration (rather than replacement) of all brass tuning components is standard procedure

 

[mvhbiker]

did you clean the fuel vent?

bpe's guide to servicing your gas cap, careful with the ball bearings

I have not, I will look into that, thank you.

 

[mvhbiker]

I'd be highly suspicious of any non-stock tuning components from a "carb kit". Note the size differences documented in my attached pic.
Also...within your efforts have you analyzed the petcock function? Possibly something amiss there as well.

View attachment 57657

Ok, understood. It seems as if the kit worked temporarily, but I am now experiencing similar problems, I will try servicing O.G parts and see if that fixes the problem. If not I will order the OEM parts from part zilla.[/QUOTE]