[Mirelx]

Hi everyone,i bougt a Kawasaki vulcan 750 it was not running the seller told me that he didnt have battery for it and that with the battery would probably start,well it didnt and i got it for cheaper price. After countless tries i started it up 2 times,first time it was running ok and i found out the gas has disconected so i turned it off,second time i was able to turn it on it was runing on 4k rpm by itself. After that i started it up for a minute with the start spray and after that nothing. The bike have spark,new battery new spark plugs,new petcok,fresh fuel. Also when cranking the bike sometimes theres some pops from the exhaust but no start. I wanted to take it to mechanic shop but they said they dont repair bikes older then 20 years old.

 

[Spockster]

Hi everyone,i bougt a Kawasaki vulcan 750 it was not running the seller told me that he didnt have battery for it and that with the battery would probably start,well it didnt and i got it for cheaper price. After countless tries i started it up 2 times,first time it was running ok and i found out the gas has disconected so i turned it off,second time i was able to turn it on it was runing on 4k rpm by itself. After that i started it up for a minute with the start spray and after that nothing. The bike have spark,new battery new spark plugs,new petcok,fresh fuel. Also when cranking the bike sometimes theres some pops from the exhaust but no start. I wanted to take it to mechanic shop but they said they dont repair bikes older then 20 years old.

Low cranking voltage will cause backfiring on this bike, it likes an AGM battery. A wet cell that's been cranking a bit will be weak.

If the choke is on that will make the rpm stay high.

Lean fuel mixture can cause popping. Does it try to start on the spray?

 

[Mirelx]

Yes it it was starting on the spray last time it was running,i tried starting the bike today with the start sprey and no luck. Again the bike have spark,have compression,have new battery and sparkplugs. You can tell that something is happening inside the cilinders like its trying to lit up the fuel but wont fully start the engine. I was thinking maybe carburators but i wanted more opinions before i figure out what to do with it.

 

[Spockster]

Yes it it was starting on the spray last time it was running,i tried starting the bike today with the start sprey and no luck. Again the bike have spark,have compression,have new battery and sparkplugs. You can tell that something is happening inside the cilinders like its trying to lit up the fuel but wont fully start the engine. I was thinking maybe carburators but i wanted more opinions before i figure out what to do with it.

Not sure at the moment. If it was just the carbs, it should fire up with some spray.

I know you said the battery is new, but what is the voltage? Is this a wet cell or something else? AGM, gel?

 

[Mirelx]

I think the battery is AGM i didnt check the voltage im not that good in electrical field but im gonna try to check the voltage gonna do some research how to. What kind of voltage does it need to start?

 

[Spockster]

I think the battery is AGM i didnt check the voltage im not that good in electrical field but im gonna try to check the voltage gonna do some research how to. What kind of voltage does it need to start?

I'd want to see 12.7 to 13.1v.

 

[Mirelx]

Is it posible to be air related?
Also i played with the idle screw a little bit because it was running on 4k rpm and im affraid that that made things worse

 

[Spockster]

Is it posible to be air related?
Also i played with the idle screw a little bit because it was running on 4k rpm and im affraid that that made things worse

Have you looked at the air filters? Sometimes they fall apart and clog up the airbox and intakes, even end up going through the combustion chambers.

Where were you putting the spray?

The idle setting shouldn't keep it from starting if you're using the choke. It should at least fire.

 

[Mirelx]

The filters are ok and i took off filter to spray starting fluid trough the intake

 

[ZCraggRatt]

I'm really not sure if this is the right time to mention such a thing, but I will anyway. These bikes have shown to benefit from a particular mod to the ignition pickup coils. The idea, is that the pulse created by the permanent magnets/pickup coils becomes weakened over time. While there are exceptions, most owners have reported a dramatically easier start after making the mod to the pickup coils. The mod is to move the pickup coils closer to the permanent magnet. Most cite setting the distance at .020". I also know that this mod made a measurable improvement in the ease of starting for my bike. No more hard hot starts, and no more shotgun blast backfires. It could be that while there may be some critical adjustments required for your bike to start and run well, this mod could help with that.
It's a relatively easy zero cost modification to make, even if you are not mechanically inclined. It sounds like you have a good sense of whats required for the engine to run, but may not be familiar with the specifics of this engine. I think you could do it after reviewing the procedure here on this sight. I recommend it.
Secondly, If you ever want to check it, I have a relatively stock setup, and run my air/fuel mixture screws just shy of 2 complete turns out from seated.