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Pretty confused on this, bike ran up and started fine.It’ll backfire but won’t start. The bike sat for a few years but no gas was in the carbs. I cleaned and drained the lines and tank and put fresh gas in, bike ran and started up fine. But once i dropped it, it won’t start.Has a spark on every cylinder, caps each go to the right cylinder, new plugs because the old ones were pretty fouled but all still worked. thought it was flooded plugs were really wet, took the plugs out and cranked it over for awhile. Sat for a few days, still nothing. Carbs are getting gas Spark on each cylinder not sure why it doesn’t want to start, gave me a loud pop and a flame today after sitting for a week
 

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Pillion Cam
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fuel pump sounds like its working if you're getting gas. Maybe check to see if the carbs didnt come loose.. check for vacuum leaks.

Have you tried hitting the intakes with starter fluid. Any difference with or without choke?
 

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Discussion Starter #3
fuel pump sounds like its working if you're getting gas. Maybe check to see if the carbs didnt come loose.. check for vacuum leaks.

Have you tried hitting the intakes with starter fluid. Any difference with or without choke?
Haven’t tried starter fluid, air box is off right now, didn’t start when it was on but I was having a hard time keeping the boots from the air box to the carbs on. Could that be part of it I had it pretty tight when it was running, I thought i had them on alright the second time but you can still easily pull it off.Also I drained the oil and a small amount of water was it it. However the bike was left outside for a year or two with the starter cover cracked off, I also didn’t lose any coolant so I don’t think it’s a head gasket. There was also a lot of fuel in the oil. I have spark but could it be weaker as a safety mechanism I have an oil light on
 

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Pillion Cam
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If the boot between the carb and head pops off easy, could cause troubles. The air/fuel isnt mixing right. Water in oil could just be condensation. Gas smell in oil could be engine flooded. Maybe just a result of when it tipped over the carbs dumped gas into cylinder. Also would explain fouled plugs.

When it tipped over, sounds like something may have jarred loose. Wouldn't be a bad thing to tear the carbs down, clean them and make sure floats and everything are in spec. Make sure no debris got in the passages or float didnt pop off the float needle or anything weird like that. Maybe check the boots for cracks.. old bike, sitting a while, the boots may be dry, hard, or starting crack. Had to change out the boots on a 97 ninja because the rubber dryrotted. Was not very pliable and showing lots of little cracks where the band clamps were. If they look good and are just hard there are things you can do to soften them up a bit.

If you can get it to run at all, check boots for leaks. That at least is start for checking air/fuel. Checking spark and electrical troubleshooting a bit of a different beast.

Good luck, be patient. 30 year old parts can be temperamental. Lol
 

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Discussion Starter #5
If the boot between the carb and head pops off easy, could cause troubles. The air/fuel isnt mixing right. Water in oil could just be condensation. Gas smell in oil could be engine flooded. Maybe just a result of when it tipped over the carbs dumped gas into cylinder. Also would explain fouled plugs.

When it tipped over, sounds like something may have jarred loose. Wouldn't be a bad thing to tear the carbs down, clean them and make sure floats and everything are in spec. Make sure no debris got in the passages or float didnt pop off the float needle or anything weird like that. Maybe check the boots for cracks.. old bike, sitting a while, the boots may be dry, hard, or starting crack. Had to change out the boots on a 97 ninja because the rubber dryrotted. Was not very pliable and showing lots of little cracks where the band clamps were. If they look good and are just hard there are things you can do to soften them up a bit.

If you can get it to run at all, check boots for leaks. That at least is start for checking air/fuel. Checking spark and electrical troubleshooting a bit of a different beast.

Good luck, be patient. 30 year old parts can be temperamental. Lol
Ok my next thing is the carbs but I still don’t understand what changed from it dropping engine flooding makes sense but I changed plugs
 

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Pillion Cam
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Something probably just jarred loose on tip over. While have it apart thats when you can check pinched wires, vacuum lines, and such. And one thing I have learned about carbs.. you can never go thru them and clean them too much..lol

My YZF600R (successor/sibling to the FZR) tends to be really finnicky about starting and running anytime I had a drop.
 

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Discussion Starter #7
Something probably just jarred loose on tip over. While have it apart thats when you can check pinched wires, vacuum lines, and such. And one thing I have learned about carbs.. you can never go thru them and clean them too much..lol

My YZF600R (successor/sibling to the FZR) tends to be really finnicky about starting and running anytime I had a drop.
I’ve been trying to figure out if my bike has a tip over sensor, fuel pump runs and I have spark could there still be an electrical problem?
 

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Pillion Cam
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I dont know of any bike of that vintage or even carburated that would have a tipover sensor. Those are computer controlled and would cut spark, injectors, fuel pump, or any combo of.. and you said you have spark and fuel. Does it even try to fire or is it dead? I know you mentioned before a couple big pops but that's it.
 

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I dont know of any bike of that vintage or even carburated that would have a tipover sensor. Those are computer controlled and would cut spark, injectors, fuel pump, or any combo of.. and you said you have spark and fuel. Does it even try to fire or is it dead? I know you mentioned before a couple big pops but that's it.
That’s what I thought, but wasn’t sure. It pops occasionally but rarely. I cracked the drain bolts on all the carbs and they all are getting gas. Came of pretty clean too, they don’t leak either and were stored dry. I took the gas tank off so I could get the air box boots on the carbs tightly. I haven’t tried starting it since I drained the oil I’m going to try to flush it out and see if the water was condensation which seems to make sense because I didn’t loose coolant and it doesn’t have oil in it, the cylinders were dry besides gas.
 

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Pillion Cam
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Thats good. I am willing to bet the milky oil was condensation from sitting.. if it was running and upto operating temp, that would boil off and be fine. Mine gets a little cloudy after i winterize. Have you checked the jets and floats? make sure there wasnt any debris up inside or float valve didnt pop out. if you have good voltages and spark and fuel in the bowls, the carbs seem like the culprit... have you tried a quick spray of starter fluid or trying with and without the choke?

Could give the choke and throttle cables a quick check to make sure something didnt pop off or come loose there.

Any vacuum lines come uncapped or anything.

I wish I had more ideas.. just on my own experience, these symptoms on this type of bike is finnicky carbs or wiring issue regarding the CDI / coils.

I wish i was more help.
 
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