Fzr 600 troubleshooting sorry not a fz6

1991 fzr 600

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Please ignore the model I can’t find many active forums. My 91 fzr 600 fell over in the driveway. Usually not a big deal, wouldn’t start after assumed it was flooded. Now weeks later it still won’t start. Ran fine before this nothing that’d suggest carb issues. If it’s sits long enough it will give a shotgun blast from the pipe but other than that nothing. Won’t pop off starter fluid either. Has spark and as far as I can tell compression
 

TownsendsFJR1300

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I don't see a tip over switch so that's not an issue..

Couple things to check and give a definite answer:
-Make sure battery is fully charged, perhaps "load test" as well. You need full voltage
for the engine to run. Plz post what the voltage of the battery is as of now..

-If the battery is fully charged and the engine cranks/spins over properly, pull the spark plugs, ground to the head and crank over. Ascertain you DO have a good spark for all cylinders-Post back the results...

-Should you have a good battery (passed load test) and good spark, spritz some fuel thru the air filter box (filter removed) and see if she fires off.


-It does have a fuel pump (part #47): https://www.partzilla.com/catalog/yamaha/motorcycle/1991/fzr600rb/fuel-tank

You need to ascertain that both the fuel tank valve DOES ALLOW FUEL to flow (IE, attach another test hose to valve), turn on and see if fuel actually leaves the valve /tank.

-Back to the fuel pump, . Should you have fuel flow from the tank valve check to see if the fuel pump is indeed working. You can remove it, apply 12 volts to it with a test hose hooked up to to it sucking from a liquid supply (obviously if using gas, be careful) .

-Carbs. Part #25(pictured below) is the DRAIN PLUG/screw. When removed, fuel should empty from the carburetor(s). Ascertain fuel is indeed getting there and comes out when the drain screw is opened(CC)..

That should get you headed in the right direction..


*I'd be leaning towards it being a fueling issue, valve/pump, possible carbs just due to age crappy fuel now-a-days..


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1991 fzr 600

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I don't see a tip over switch so that's not an issue..

Couple things to check and give a definite answer:
-Make sure battery is fully charged, perhaps "load test" as well. You need full voltage
for the engine to run. Plz post what the voltage of the battery is as of now..

-If the battery is fully charged and the engine cranks/spins over properly, pull the spark plugs, ground to the head and crank over. Ascertain you DO have a good spark for all cylinders-Post back the results...

-Should you have a good battery (passed load test) and good spark, spritz some fuel thru the air filter box (filter removed) and see if she fires off.


-It does have a fuel pump (part #47): https://www.partzilla.com/catalog/yamaha/motorcycle/1991/fzr600rb/fuel-tank

You need to ascertain that both the fuel tank valve DOES ALLOW FUEL to flow (IE, attach another test hose to valve), turn on and see if fuel actually leaves the valve /tank.

-Back to the fuel pump, . Should you have fuel flow from the tank valve check to see if the fuel pump is indeed working. You can remove it, apply 12 volts to it with a test hose hooked up to to it sucking from a liquid supply (obviously if using gas, be careful) .

-Carbs. Part #25(pictured below) is the DRAIN PLUG/screw. When removed, fuel should empty from the carburetor(s). Ascertain fuel is indeed getting there and comes out when the drain screw is opened(CC)..

That should get you headed in the right direction..


*I'd be leaning towards it being a fueling issue, valve/pump, possible carbs just due to age crappy fuel now-a-days..


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View attachment 73665
Should’ve been more clear in my post, and this is why this is stumping be so bad. Battery is fully charged, spark on all cylinders, carbs are clean and getting fuel. Bike won’t start even on starter fluid directly to the carbs
 

1991 fzr 600

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Check compression and valve timing..
Ok compression is 170-180 across the board, which is good. I’ll check timing as it seems to be the only option, but I was trying to figure this out could a tip over (while the bike was running if that matters) knock the timing off?
 

Gary in NJ

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If you have good compression, a strong spark and the bike won’t briefly start on starter fluid, it sure sounds like timing.

A leak-down compression test will reveal if a cam sprocket jumped out of time. Ignition timing is done at the stator via a Hall effect sensor. Perhaps that is damaged.

I’m assuming the bike fell on the right side. Do you see any impact marks?

Have you checked the connections at the ECU? How about the other connections in the electrical system. It might be worth the time to disconnect and reconnect to ensure that one wasn’t loosened in the fall. Maybe a wire was pinched from the impact.
 
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trepetti

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Weird. The basics are air, fuel and spark. Compression is good and I think everyone is perplexed by how a driveway fall might change the timing. If it won't ignite starting fluid, I strongly suspect spark.

How did you test the spark at each cylinder?
 

bigborer

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First thing I'd look for is loose and/or oxidized connectors.
Some possibilities:
-oxidation in the circuit between the CDI and plugs => it might spark but at too low current
-both the neutral switch and clutch switch not working => bike thinks you're starting it in gear

With the wiring diagram in front, I'd measure the resistance of ALL that's involved with ignition and fueling.
 

Motogiro

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If compression is near spec. then mechanical timing is probably not an issue except pick-up coil timing. Did something move where the pick up coil sensor is at the wrong position or if using a magnet for the trigger, did the magnet move?
You'd have spark but at the wrong time...
 

1991 fzr 600

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Weird. The basics are air, fuel and spark. Compression is good and I think everyone is perplexed by how a driveway fall might change the timing. If it won't ignite starting fluid, I strongly suspect spark.

How did you test the spark at each cylinder?
I grounded the plugs to the head and used a bulb tester after
 

1991 fzr 600

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If you have good compression, a strong spark and the bike won’t briefly start on starter fluid, it sure sounds like timing.

A leak-down compression test will reveal if a cam sprocket jumped out of time. Ignition timing is done at the stator via a Hall effect sensor. Perhaps that is damaged.

I’m assuming the bike fell on the right side. Do you see any impact marks?

Have you checked the connections at the ECU? How about the other connections in the electrical system. It might be worth the time to disconnect and reconnect to ensure that one wasn’t loosened in the fall. Maybe a wire was pinched from the impact.
Fell on the right side yeah, I don’t think any electronics were hit if it was the left there’s a few more things on that side to get damaged
 

1991 fzr 600

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If compression is near spec. then mechanical timing is probably not an issue except pick-up coil timing. Did something move where the pick up coil sensor is at the wrong position or if using a magnet for the trigger, did the magnet move?
You'd have spark but at the wrong time...
How can I test that?
 

Motogiro

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You'll want to find your pickup coil. Some Yamaha bike used what is a call a pulsar type pickup coil. It must have a specific gap to work properly and produce correct voltage for reliable triggering.
If you don't have a service manual you might get one to help you trouble shoot and service your bike.
 

TownsendsFJR1300

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Fell on the right side yeah, I don’t think any electronics were hit if it was the left there’s a few more things on that side to get damaged

Under the right side, smallish engine cover, is the pick up coil for the ignition.

Can you post some pic's of the damaged area?

.
 

1991 fzr 600

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Under the right side, smallish engine cover, is the pick up coil for the ignition.

Can you post some pic's of the damaged area?

.
Will do there wasn’t much damage anywhere the bike was layed down at speed on the side in 2016 and sat before I got it fell over on the same side thought
 

1991 fzr 600

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Will do there wasn’t much damage anywhere the bike was layed down at speed on the side in 2016 and sat before I got it fell over on the same side thought
Will do there wasn’t much damage anywhere the bike was layed down at speed on the side in 2016 and sat before I got it fell over on the same side thought
Though*
 

1991 fzr 600

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Under the right side, smallish engine cover, is the pick up coil for the ignition.

Can you post some pic's of the damaged area?

.
The pickup coil is on the left side of the fzr, it’s the little sensor that picks up on the flywheel right? This is a pic a little corrosion, is it too much for it to work though
 
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