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Discussion Starter #1
Thanks to everyone for their contributions to the knowledge here I've got the bike running fairly well for an old girl. around town and less than 60 mph is nearly flawless operation. the power is improved at all rpms but let me start from the beginning. my wife rode this bike for two years and we never did much to it since buying it she said it had issues at highway speed. I did the fuel cap cleaning for poogs and she said there was some improvement. we also gapped and checked plugs and did some seafoam. mild improvements she said. I got the bike and my analysis was there was a bog at 4500-5500 rpm and as long as I got above that quickly and shifted to 5th I could go just fine from 65-85mph. and I continued the sea foam the bog got better but not completely gone.

this fall I pulled the carbs and cleaned and checked everything and replaced the vac petcock with a tw200. the power increase was immediate and noticeable and no bog so I thought everything was great, however after beating the bike through a few corners it begins to hesitate and on the highway it will go fine right to 75 but then after 60-80 seconds begins to miss and lose power and cant maintain 55 barely down shifting does nothing and opening the gas cap does nothing

I have so far:
cleaned the carbs
replaced petcock
cleaned the tank vent
checked the bowl vents (45 deg, in right ear)
cleaned air filters
checked carb boots (had a slight leak gone now no change)
replaced plugs
checked coil wires
checked grounds
checked battery connections
cleaned ignition contacts
wiggled key and turned on/off no change
rode with tank open

when it occurs it will cut in and out and have full power for a split second, almost causing a buck, rolling off and on the throttle doesn't help. it sounds like a dead cylinder or a decel almost.

even though I have cleaned the tank vent and it seems to flow, when I open the cap, I hear a hiss briefly, like it is sucking in air, but I don't think its related because the problem is present when the cap is open and if I ride her gently around at 35-45 mph she goes great with no apparent problem for many miles and the tank vents fine. this may be electrical but it could be a carb issue I will post in both maybe?? thanks for any insights guys!
 

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Thanks to everyone for their contributions to the knowledge here I've got the bike running fairly well for an old girl. around town and less than 60 mph is nearly flawless operation. the power is improved at all rpms but let me start from the beginning. my wife rode this bike for two years and we never did much to it since buying it she said it had issues at highway speed. I did the fuel cap cleaning for poogs and she said there was some improvement. we also gapped and checked plugs and did some seafoam. mild improvements she said. I got the bike and my analysis was there was a bog at 4500-5500 rpm and as long as I got above that quickly and shifted to 5th I could go just fine from 65-85mph. and I continued the sea foam the bog got better but not completely gone.

this fall I pulled the carbs and cleaned and checked everything and replaced the vac petcock with a tw200. the power increase was immediate and noticeable and no bog so I thought everything was great, however after beating the bike through a few corners it begins to hesitate and on the highway it will go fine right to 75 but then after 60-80 seconds begins to miss and lose power and cant maintain 55 barely down shifting does nothing and opening the gas cap does nothing

I have so far:
cleaned the carbs
replaced petcock
cleaned the tank vent
checked the bowl vents (45 deg, in right ear)
cleaned air filters
checked carb boots (had a slight leak gone now no change)
replaced plugs
checked coil wires
checked grounds
checked battery connections
cleaned ignition contacts
wiggled key and turned on/off no change
rode with tank open

when it occurs it will cut in and out and have full power for a split second, almost causing a buck, rolling off and on the throttle doesn't help. it sounds like a dead cylinder or a decel almost.

even though I have cleaned the tank vent and it seems to flow, when I open the cap, I hear a hiss briefly, like it is sucking in air, but I don't think its related because the problem is present when the cap is open and if I ride her gently around at 35-45 mph she goes great with no apparent problem for many miles and the tank vents fine. this may be electrical but it could be a carb issue I will post in both maybe?? thanks for any insights guys!
I don't know if this will help, but you may wanna consider the fuel lines. Maybe you have and I missed it. I don't have much experience with motorcycles (only been riding a month), but boats kinda act the same way. And when they sit up and that ethanol gets in them, it is difficult to get out. It will also ruin the fuel lines quick when it sits. I had the same problem with a boat. Idled great, would run low RPM fine. But WOT (wide open throttle) sucked. Turned out my fuels lines were restricted and it couldn't get enough gas. They had swollen-probably caused by an additive or-ETHANOL

Again, this may have nothing to do with what you are experiencing. Just shooting from the hip. I use regular gas on my moto, but only ethanol free in my boat because it sits for longer periods.

And remember, water is heavier (more dense) than gas and oil so if there is any moisture in that tank it will go to the bottom. Have you drained the tank completely, let it dry then tried new gas? Again, just a suggestion.

Hope ya get it figured out man..........Sorry I could be more help.
 

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2014 KLR 650!
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3,365 Posts
Ignition switch. clean it again and stretch the springs ever so slightly. Make sure the puck is on tight with a zip tie and super glue.
 

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Discussion Starter #4
new stator was junk "caltric" on ebay never buy from them total garbage and they wont help me out when this problem was there the first day but the stator was partial charging so it took me a month to figure this out but I think I got it unless the stumbling is also another different problem :BLAM:
 

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Chasin' the blacktop
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1,498 Posts
I'm also thinking fuel but something to consider. My bike would sometimes start stuttering occasionally like one cylinder was cutting out. I kept thinking fuel then also but it turned out to a poor connection on the positive wire to the rear coil.

Still' Since your problem tends to happen between 50-65mph I'd make sure your carb vent line is in dead air.
 

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Old Truck Junkie
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4,133 Posts
Make sure that your right side front spark plug is not shorting against the throttle cables.
 

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Discussion Starter #8
wasn't sure if it was fuel or ignition so I put it in the two sections anyways...
bike is charging again but the running issue is still there! I went out for a ride and a few minutes in I could tell the problem was still there, the front cylinder is having some kind of misfire. when I put my hand over the pipe outlets the rear cylinder feels hot, the front feels luke warm at best, but if I rev it, it will heat up a bit. pulling a spark wire shows a strong spark so I don't think its ignition related but I could be wrong. I am thinking carbs, so I pull the front cyl boot and the slider is bouncing!, I pulled the other side and it was also bouncing, but at that point it was running noticeably worse since both boots were disconnected. I think I am going to pull the carbs one more time and check jet sizes, floats, and sliders I need to get this fixed by end of august for a trip with my wife so frustrated!!!:BLAM::BLAM::BLAM:
 

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Discussion Starter #9
also pulled a plug to the front cylinder and it looked remarkably clean so I am leaning toward carbs
 

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Discussion Starter #10
the problem is at all speeds now but I cant go faster than 65 unless I get it in 4th and ride full wide open throttle
 

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Discussion Starter #11
I have run through several tanks near empty and run sea foam several times and all through the spring so I doubt its water/ethanol contamination
 

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Old Truck Junkie
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Sounds electrical. Check connections at the coils. Pull connections off and reconnect. Make sure the plug wires are not leaking electricity. Run the engine at nite and check for sparks along the plug wires. Also the vacuum hose can cause low fuel delivery to the carb. Make sure that hose is not cracked. Make sure that fuel lines are not kinked.
 

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Discussion Starter #13
I was going to pull the carbs again (3rd time) but decided I would start her up real quick and she was running perfect again its not as humid and cooler today I am going to just replace the original 20 something year old wires any recommendations on a part number of some universal kit?? and I may swap the coils and see if it changes cylinders, I did check the coil connections they seem very tight no corrosion etc I will update after the wire change and coil swap and see what happens
 

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Old Truck Junkie
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There is also a connector that comes out at the same place that the stator wires do. They are for the pick up coils, you may disconnect and reconnect to make sure you have good connection there.
 

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Discussion Starter #15
There is also a connector that comes out at the same place that the stator wires do. They are for the pick up coils, you may disconnect and reconnect to make sure you have good connection there.
I will check that I have not looked into that yet but I did find a kink in the hose to the front carb so I fixed that and I will let you know how that goes thanks
 

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Discussion Starter #16
so far so good! bike ran great all day on three rides going on a longer ride Friday to test it for real :pepper::rockon::motorcycl
 
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