Need Help. Cleaned carbs now no starting

Really appreciate all the suggestions. I'll have to dig out my multimeter to check the coils. This afternoon I gave each carb a quick shot of carb clean and it fired right up. Ran for about 3 minutes then shut off. Wouldn't fire back up without more carb clean but besides the initial squirt, I didn't give it more, so it must have been running on fuel alone for a bit. Could the header mating cause any issues? I've got the zr7s headers on it and with them having cross over tubes between headers, they push up against the oil cooler lines and don't seem to be sitting quite flush against the head. I ordered a Delkevic full exhaust today as I had trouble finding a suitable replacement used on the net.

I'm thinking it's got to be the carbs in some way.  It's almost as if there is a vapor lock keeping the engine from sucking fuel up from the float bowls.  Could your gas tank have a lot of sludge and/or rust that got into your clean carbs?  

For starting, full choke, and don't touch the throttle.  Make sure the throttle stop is opening the throttle plates enough to keep the bike running.  

From everything you have written, it should run.  I'm at a loss.  

Yes its possible the tank got some debris into the carbs. I had used evaporust and water in the tank, letting it sit to clean it out. I thought I did a good job hosing it out afterward but maybe not. I've got an auxiliary tank now for the fuel so I don't have to take the tank on and off. I did try starting it the first few times with the tank on it so maybe that's were the issues started. I really do appreciate all the suggestions, like you I feel stumped. 

As a side note, when I did the compression test first thing this morning I cranked it over first without any of the spark plugs in and didn't get any fuel out of the spark plug holes. I was wondering if there was a spark issue and I was flooding the engine but that crossed that off for me.

So I believe I stated in an earlier post I had bought new BR9ES spark plugs and had put them in before trying to start the motorcycle initially. This past Friday when the bike ran for a few minutes, I had reinstalled the mismatched 8 heat level spark plugs. This morning, I put the BR9ES plugs back in and it wouldn't fire up at all. 

Could the heat range be part of my issue even though I've got the spec'd plugs per the manual? Would it be worth trying a hotter and cooler plug to see if that gives me different results?

84_GPz750 wrote:

So I believe I stated in an earlier post I had bought new BR9ES spark plugs and had put them in before trying to start the motorcycle initially. This past Friday when the bike ran for a few minutes, I had reinstalled the mismatched 8 heat level spark plugs. This morning, I put the BR9ES plugs back in and it wouldn't fire up at all. 

Could the heat range be part of my issue even though I've got the spec'd plugs per the manual? Would it be worth trying a hotter and cooler plug to see if that gives me different results?

The factory manual calls for BR9ES spark plugs.  The heat range won't have any effect on getting the bike running.

Thanks Ed. It started up and ran the longest with the hotter plugs which is why I asked. There's something I'm overlooking, just have to keep digging to find it. 

Did you check the supply voltage at the coils ?
Can you smell fuel in the exhaust when you have been cranking the motor ?

i know possibly dumb questions... but reading through the conversation so far:
is the idle set really high or really low?
are the fuel screws turned in too far (running very lean on idle)? (looking at lean, because if they're out way too far, starting fluid is adding *more* fuel to an already rich scenario, and is unlikely to run)
are the choke(s) operating as desired? if i recall correctly, the choke uses different passages than the normal pilot/idle speed circuit.

running on "starting fluid" and nothing else, it would seem it has compression and spark. speaking of spark, the cables didnt get swapped to the wrong cylinders while checking spark?

is the throttle cable sticking/hanging so there's not enough vacuum to pull any actual fuel through?

have we tried going through the whole sequence, one step at a time? i'm not sure how you're working through the suggestions here. Looking at just the suggested items, possibly skipping a "doh!" moment?

if I'm way off base, please let me know. I'm learning as well.

It appears it’s no longer starting on the spray ?

Any rust flakes or particles in the float bowls? Might be a good idea to run an inline fuel filter.

You mentioned it died after a few min, so if you do get it running, I'd recommend leaving the float height measurement tubes on, so you can check the level while running.

First of all, thanks everyone for chiming in with ideas. I measured 12.97V to both coils today. As far as smell, when it ran for a few minutes it certainly smelled like fuel. I had only given a small squirt of starting fluid and once it fired up I didn't give it more. 

The last two mornings I've messed around with it, it won't fire even with a small squirt of starting fluid and it usually gives an initial puff of smoke out the exhaust that smells hot for a lack of better explanation. I double checked the plug wires and they are correct, LH coil goes to #2 & #3 and RH coil goes to #1 & #4.

@Saablord when I pulled the float bowls off a week ago to check the float heights, I did not see any particles or crud in them. I do have an inline fuel filter now, but only installed it after switching from using the stock fuel tank to an aux fuel canister for this troubleshooting.

@KeylAmi! I set the carbs up following @Nessism's guide. I believe the fuel screws are 2.5 turns out.

What is the coil voltage when cranking?
I meant can you smell fuel in the exhaust when it doesn’t start 
PS: is your auxiliary fuel supply vented?