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Discussion Starter #1
So I was doing a pretty lengthy ride today, and the bike just dies without warning. Has plenty of fuel. So I let it sit for a minute and it fired right back up, only to die a couple minutes later. I remember a thread about this issue and thought I'd post about it in case I should look for anything else
 

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Classic symptoms for ign pick up fail, but a blocked fuel 'duckbill' filter, or blocked tank vent could look similar.
 

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How long do you have to let it set, Austin? 20-30 minutes? I'd say it's the pickup coil. 5-10 minutes? I'd say it's a fueling problem, along the lines of what Mike is talking about.
 

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Discussion Starter #4
5-10 minutes before starting. I'll try blowing through the tank vent line and see if it's clogged..
 

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Stoppage

Have you had the fuel tank of recently? If so the breather pipe may have been kinked when replacing or the tip over valve stuck. Ride with the fuel cap undone a thread or two, if engine still conks out you have disqualified these two.
 

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Start the bike, turn off the petcock, run it till the carbs are dry. Remove the fuel line from the carbs at the fuel rail, remove the duckbill filter, clean it/ blow it clean.
Take the gascap off, hook up your air line to the fuel line going to the petcock with an air blowgun. Open the petcock and blow some air thru the fuel line, petcock, and filter in the tank. Do it on run and reserve. If you have any crap accumulated on the screen in the tank, this will clear it out of the way. Close the petcock, and then blow some air thru the vent line making sure it's clear.
 

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To rule out a fuel issue after cleaning the duckbill ride around with the petcock on reserve.

On my Adventurer I cleaned the hell out of the duckbill, carbs, petcock, tank, tank vent, new fuel line and it would still fuel starve. I drilled some holes under the gas cap into the plastic and it still starved. Ive been running the bike with the petcock on reserve and haven't had any issues.

I had taken the petcock out and apart, cleaned in ultrasonic cleaner twice and it still doesn't want to run right in the on position. Been running in the reserve position for a year now with no issues. I guess the screen and tube for the on flow path are pretty crudded inside and I couldn't get it clean. Keep track of you mileage and you'll be fine.
 

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Discussion Starter #8
So it's not the fuel vent line or petcock. Turns out I have no duckbill filter, but I do have an inline filter that doesn't look clogged. I let the bike run (this thing is a pain in the ass to start when cold) and it didn't even reach the point to where the fans come on before it died again. It definitely got up to running temp though. Another thing I noticed is that there is smoke coming out of the breather hose, through the filter I put on it. I recently changed the breather seal in regards to that issue but there's still smoke coming out. Probably not related but I don't think it should do that haha.
 

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Discussion Starter #9
So I checked the gap between the pickup sensor and the lobe on the rotor, and it's around 3mm. 6-8mm is the correct gap isn't it?
 

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I just checked the manual, 0.6-0.8mm. Preferably 0.6mm. That's .024" .
3mm would be just a hair short of 1/8"! That's way too much. I'm surprised it even ran at that gap.
 

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Discussion Starter #11
I may have forgot a period before that three haha. It was .3mm. So at the tighter gap, would that cause the bike to stall out when it gets up to normal operating temp?
 

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Discussion Starter #12
So I'm starting to think the issue is temperature related. It dies exactly when the fans need to come on every time. I know it isn't fuel, it gets plenty. I re-gapped the sensor to the correct gap and still cuts out when it gets warm. Would a faulty temperature switch make the bike cut out? Is there a fail safe feature that cuts the engine when it gets too hot?
 

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Fit a new ignition pick up - it looks very likely the fault, and even if not, it's a part the bike will probably need some time. It's an item I take on longer trips, as it's not a readily available part.

It is possible the 0.3mm gap may have contributed to its breakdown. The current pulse induced in the coil (with very thin wire) is inversely proportional to the gap, so over twice the designed max with that gap (albeit with a bit of safety margin in that). The heat generated within the coil is proportional to current squared. And there's already enough heat inside the crank case to take electrical windings near their limits.
 

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5 to 10 minutes just seems like way too short of a time interval for that sensor to cool down and start working again. But I'm comparing it to when mine went out. It took 20-30 minutes for it to cool down long enough to start working again. And then I'd only get about 2 minutes of run time before it would heat up enough to go open again. Of course, it was summer time when mine failed.
I'm still thinking it could be fuel. I would get rid of that inline filter that's installed on your fuel line. I had one on mine from the previous owner, and I had to get rid of it. You don't have a whole lot of head there to push the fuel thru one of those filters (only a few inches of water column) when the tank gets low. Putting that in perspective, 1 psi equals almost 28" of water. A full tank will only yield about 0.5 psi, or 14" w.c. of head to get thru a fuel filter, and that's with a functioning vent on the tank. It doesn't take much to bodge the whole fuel delivery thing up.
 

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Discussion Starter #15
Even after I corrected the gap, it would still die. It did however last about a couple minutes longer (went through almost two cooling cycles) before it died. I'll order the sensor. I am however losing coolant, and there's no puddles. When I changed my oil it didn't look milky, but I am getting some steam coming out of my exhaust. Looking like early stages of a head gasket failure. I'll ditch the inline filter, replace the sensor, and start diagnosing the coolant issue.
 

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Temp sensor: I'm not sure if that will disable the motor in event of an over heat. Fire up the motor and try unplugging it, see what happens.

The fan sensor/switch under the gas tank will not cut the motor off it it's bad or unplugged.
 

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Even after I corrected the gap, it would still die. It did however last about a couple minutes longer (went through almost two cooling cycles) before it died. I'll order the sensor. I am however losing coolant, and there's no puddles. When I changed my oil it didn't look milky, but I am getting some steam coming out of my exhaust. Looking like early stages of a head gasket failure. I'll ditch the inline filter, replace the sensor, and start diagnosing the coolant issue.
If you do one thing at a time, you'll find out what the real culprit is. I know, time is always a factor.
 

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You can use an in line filter as long as it is designed for a gravity feed system. Don't double up with the duck bill filter, though.

Don't go looking for (head gasket) trouble. If you're running it stationary you probably just have condensation in the exhaust.
 

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Discussion Starter #19
The only reason I suspect the head gasket is because I lose a lot of coolant and I don't see any puddles anywhere.
 

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How much is a lot? What does your exhaust smell like? If it is burning a lot through combustion it would push it out the overflow and your exhaust would smell funky.:)
 
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