fuel starved when cold i think

[ptrumblejr]

I have an 85 Aspencade that runs like its on 2 cylinders when its cold. if you choke it it will idle but cant accelerate at all until it warms up to at least 2 bars on the temp gauge. I just purchased the bike and it been only in the 30s for a high but my 83 runs no problem in this weather. could this be a bad fuel issue or bad plugs maybe. when i test drove it the outside temp was in the 30s and i had to choke it a little while going down the road but once i did it took off like a rocket. Any help would be greatly appreciated

.

[joecoolsuncle]

move to America. or accept the fact that you have to warm up a bit. as timee went on, engines had to run leaner per epa, per carb, per govt mandates.

[ptrumblejr]

I live in America. What a rude response.

[joecoolsuncle]

sorry mr trumble, i thought you lived further north, where you have to warm up and run choke for awhile.

[Shadowjack]

Has this bike always done this, or has it started lately? Has it sat around long enough for fuel to congeal in some of the pilot jets? Because this is one of the classic symptoms of blocked or restricted pilot jets. Tried anything like Seafoam or Techron to see if it helps?

[ptrumblejr]

I believe I have found the problem. I think the fuel pump is faulty and not pumping fuel causing it to have to be choked to run. It also wasn't stopping the fuel from gravity feeding out of the tank when the key was off and allowed cylinders to fill with gas. Changing the oil, filter, plugs, and fuel pump. I'll see if that changes anything.

[Shadowjack]

Well, a 1200 doesn't have a "choke" where there's a blade across the airstream, restricting the air and causing the fuel mix to become richer. It's a separate enrichener circuit that feeds more fuel into the port. Since the air is not restricted, there's no additional vacuum in the port, so it can't suck harder when the "choke" is on and pull more fuel up from the float bowl.
A slow fuel pump wouldn't have much to do with that, since there's a Y splitter between the left and right pairs of carbs and they should all get the same amount of fuel unless your fuel line is restricted to one side. But that's not your symptom, since you said it took right off when choked.
The carburetor float needles should shut off the fuel when the bowls are full, so a fuel pump with leaky check valves would make no difference, unless of course the float valves are leaking as well. If all those were bad and leaking fuel into the cylinders, it could conceivably hydro-lock one. That would be bad. But it doesn't sound to me like that's what your problem is. I'm still sticking to partially plugged slow jets, since it gets better when warmed up. It does get better then, right?

[ptrumblejr]

It did in fact hydro-lock. I had to pull the plugs to get the engine to turn over. If the float is stuck I can fix that. Im not sure about your choke explanation. That would be a new one for since it's not fuel injection. I'll look into it further.

[joecoolsuncle]

alwayd turn off the petcock when parked for more than a few minutes. the fuel pump will not stop the fuel from gravity feeding and the left bank carbs will take on more fuel while leaned on side stand. depending on angle, the fuel level will increase to the point that it creeps into the intake. a carb that hasnt been cleaned and serviced for a long time, or has some trash lodged in it will give your symptoms.
what if, your left bank was actually flooded but temp was cold enough that you had to use enrichener (choke) to start bike and run on right side only, then when you hit the street, gave it some throttle, it burned off the excess in the left bank, took off and ran good.????
try this. park bike on center stand with petcock off. next day, while still on center stand, start bike and run until it hiccups and dies. now turn on petcock and restart, using enrichener (choke) to dial in fastest idle . allow to warn up, slowly adjusting choke.
will it idle now? will it take throttle? note: it may take 30 minuntes or so to reach operating temp.
this will help you diagnose. then you can post your findings.
peace

[ptrumblejr]

I will try that as soon as the new plugs and oil filter arrive. I also want to get some seafoam to run through it.

[ptrumblejr]

still having the same problem. bike wants to idle around 700-750rpm but i cant give it any throttle or it will die. seems 2000rpm is the magic number before even slight throttle is possible without it trying to die. it sounds like its fuel starved. I just bought this bike so i dont know the history. at the time i bought it I thought is was simple bad gas but i filled the tank with Recreation fuel and seafoam. i did close off the gas till it died then restarted but there was no change. i also havent put the new plugs in yet as i was hoping the hydro lock was the issue.

[joecoolsuncle]

clean and/or adjust the pilot jets, also known as the slow speed jets.

[ptrumblejr]

Not sure where those are. Plan on changing fuel lines. Adjusting idle speed and I have a vacuum synchronization kit coming on monday. I'll also check to see if air/fuel jet has been adjusted.

[ptrumblejr]

so after it warms up i have it idling a little over 800rpm but i can not throttle up without it bogging down and dying. if i use use the choke as i throttle up i can keep it running. i have added a compression tester to the list of things coming on monday. could the carbs be so out of sync as to cause this condition? the air/fuel mixture plugs are still intact.

[joecoolsuncle]

mixture screws will be uncovered when you service the carbs.
sync wont really affect pilot jet range much.
pilot jets are in the carb body. you will see them and main jet when you service the carbs.

remember this: running too lean, like you are, will destroy your engine in short order.almost fixing the problem will destroy the engine at a not so distant time.

[ptrumblejr]

i just pulled the plugs again just to verify spark. the bike has been up on the center stand with petcock closed since this morning. i put new fuel lines on so i know the petcock works. the #4 cylinder was loaded with gas again. could a bad carb cause these same symptoms? running too rich not lean?

[ptrumblejr]

well, if nothing else, this forum will serve as a log. Still hoping for words of wisdom though.

At this point plugs and bad gas are not the issue. The issue is not running unless choked and a build up gas in #4 when the bike is off. I went ahead and pulled the carbs(got em out hope i can get em back in). I opened #4 just to look since i wont have the rebuild kit until next week sometime. I found a very dirty bowl, which is strange since i was told the carbs had just been gone through. I removed the float and found that it had a couple of drops of a very thick brown liquid in each tank. I would imagine that would be enough to hold the pin open enough to flood the cylinder when the engine is off. I can only assume the rest of them are equally dirty. i will be replacing all of the floats during the rebuild. i have a sync kit coming too so i manage not to destroy them i should be in good shape. i hope.

[joecoolsuncle]

do you have a facebook account? see my last post. there are 12million facebookers advertising professional help to every 1 real motorcycle mechanic. key words to avoid.
we, us
discovered a new way
found a cure
yada yada.
you will not likely find a real motorcycle mechanic for your bike these days.
you will have to learn to work on your bike.
or, turn off your computer and ride around the countryside until you find a mechanic.
holler when it hurts

[joecoolsuncle]

alwayd turn off the petcock when parked for more than a few minutes. the fuel pump will not stop the fuel from gravity feeding and the left bank carbs will take on more fuel while leaned on side stand. depending on angle, the fuel level will increase to the point that it creeps into the intake. a carb that hasnt been cleaned and serviced for a long time, or has some trash lodged in it will give your symptoms.
what if, your left bank was actually flooded but temp was cold enough that you had to use enrichener (choke) to start bike and run on right side only, then when you hit the street, gave it some throttle, it burned off the excess in the left bank, took off and ran good.????
try this. park bike on center stand with petcock off. next day, while still on center stand, start bike and run until it hiccups and dies. now turn on petcock and restart, using enrichener (choke) to dial in fastest idle . allow to warn up, slowly adjusting choke.
will it idle now? will it take throttle? note: it may take 30 minuntes or so to reach operating temp.
this will help you diagnose. then you can post your findings.
peace

peat and repeat

[ptrumblejr]

i have the mechanical aptitude to repair the bike. I just have never worked on one this big and not for a very long time. Telling me to find someone Facebook is certainly not the thing to do. As to a local bike mechanic, I indeed have one in the area but I don't want to spend $1000 to have them do it. I came to this forum in hopes that it was something simple that i had missed but after a lot of troubleshooting it became clear that it was not simple so i pulled the carbs to be rebuilt when the parts arrive.

[joecoolsuncle]

wow! $1000. thats crazy. his shop rate must be $400 per hour. you can do it. you will be on the road in no time. have fun fixing and riding for the rest of the year!

[ptrumblejr]

It reflects being the ONLY vintage motorcycle shop in the area. He is ALWAYS busy too. I should be back up and running in a couple weeks. Only because it will take that long to get the floats.

[julimike54]

Unless the floats don't float or are damaged, you shouldn't need 'floats'

[ptrumblejr]

As I stated earlier on, the float in #4 was compromised. It had a small amount of a thick brown liquid in it. Going to replace the all.

[dragenrdr]

I had a 1989 1500 that had pretty much the same problem. I finally mounted a floodlight fixture on a board and slid it under the bike to keep it warm on those cold days and it worked miracles.