Bike stutters then stops

Johnny5

Johnny5

Well-known member
Bike stutters then stops (UPDATED WITH PICS 3/13)

**UPDATED WITH PICS PLEASE SEE MY POST AT THE BOTTOM OF THE THREAD**

I have an '84 honda magna v45. I didn't do anything special to winterize it this year, i rode it regularily up until xmas, then a couple times after that in janurary on nice days. Then parked it until last week, just starting it up for a few mintues once a week.

Anyway i took it out last Wednesday and rode to work and it started right up without any problems and rode well. Then yesterday i rode it for about an hour. I went and put fuel in (on top of the fuel+stablizer i had in from before xmas, maybe half a gallon of was left in it). Then on the way back from getting fuel it seemed to run rough.

This morning it wasn't starting up well, so i opened the choke a bit, then almost fully to get it to stay running and waited and gradually rolled it back to the off position but the bike was having a hard time idling without shutting down, so i started to ride to work with the choke open a bit but the bike was stuttering like mad and did a few backfires from the piples, and the rpm's kept jumping from 1k to 5k in first gear and violently rocking the bike like it was about to stall, so i pulled over and shut it off.

Then when i tried to start it up again it kept stuttering and shutting down again. Sometimes i would start it and the engine would fire but the rpm's showed zero, then the next time it would rev up but as soon as i went to go into first gear and start to roll the bike shut off. I waited about half and hour, then finally got it to stay started again by opening the choke and i made it home with it stuttering all the way and almost shutting down, it conked out at me at the last stop sign before my house and i had to walk it the last bit. It seemd ok when i was rolling in 2nd or higher, but when i was going slower it kept stuttering in first.

So just now i got home from work and started it up first try, and have been letting it run, it's idling at 1000k but sounds a bit rough and burpy. My oil levels all seem fine. Could it be the fuel i put in yesterday? a car mechanic friend thinks there might been water mixed in the tank from condensation due to the rapid temp changes this week and my garage which is not heated. Or did i flood the engine this morning by using too much choke? Maybe i should have let it warm up longer until it was idling at 1k without choke? Any ideas? Obviously it needs a tuneup but should i risk riding it to the mechanic as is if i can keep it running long enough?
 
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Might be fuel.

Might be carbs.

Might be plugs.

How old are those plugs? and when were those carbs cleaned out?

Also, if your having lack of electrical power you might see rpm jumping up/down
 
if you do have some water in the tank, you can put some gas line anti freeze in the tank to absorb the water
 
Thanks guys. What about too much choke starting it up? did i flood it maybe? I forgot to mention that in my original post but i think you replied while i was editing it. I bought the bike last September and it ran perfectly fine last Wednesday on my first ride since storing it and until today it's always started up fine on the first shot, even on the coldest days this winter. I haven't checked the plugs and i have no clue when the last time the carbs were cleaned. For sure it needs a full tuneup but i'm just wondering if it safe to ride it to the mechanic as is now. When it was jerking around i was worried it was gonna seize the engine but when i got home i checked the oil levels and they are all ok, the oil light never came on
 
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Situations like these can be difficult to sort out.. so process of elimination starting with the cheapest fix first.

That would be.. fuel. Drain all your old fuel and put some fresh fuel in there. From there, you can check your spark plugs and if that still doesn't solve it, might be that it needs a good carb cleaning.

Even though you put stabilizer in, old gas can get gummy so maybe your jets are clogged? But, as I said, start with the cheapest and work your way deeper in to the engine.
 
You say that the bike with fuel & stabilizer ran fine then you added fuel and the problems started. I'm also thinking that is sounds like water in the fuel. Alternatively it could be anything mentioned above. For your sake I hope it isn't the rubber diaphrams in the carb that have split. Those bloody suckers are crazy expensive.
 
I didn't get a chance to do anything with the bike last night. But this morning i went out and it started up fine and it seemed to be at normal power when i revved it while standing beside the bike. so i figured sweet.. the problem worked itself out. So i got on and as soon as i sat down on it and flipped the kick stand up boom.. dead.. Then i remembered i had my tank raised up last week to look at the air cleaner, and i had to tug on it a bit to get it up enough to put the little stick thing in to hold it up, so i thought hmm maybe i pinched the fuel hose when i closed it.

So i raised the tank and i see there are two hoses. One big one and a smaller one. The smaller one was pinched and looked almost totally blocked. And it was very sticky and looks like some fuel forced itself out around the end where it connects.

Is this the problem? The thing is when the tank is in the down position it doesn't have a lot of room and it appears it may have already been pinched before, but i've never had the problem until yesterday. I tried to pull it through to the other side more to straighten it up. But now when i tried to start it i got nothing because the battery is weak from all the problems yesterday and constantly trying to start it up. I have it on the tender now to charge it up.

I'm attaching a couple of pics of the hose in question. The thick one and the thin one have to travel under a piece of metal that runs between the frame and where the seat attaches. They are very pinched together with the thinner one not having much breathing room at all. Could this be the reason the bike runs fine when i'm not on it then dies when i sit down, the bottom of the seat comes very close to those hoses so maybe it's pushing on them just enough to force that small hose to kink? And would that one small hose being almost blocked be enough to stop it from running? There is a reserve tank and i'm guessing thats the hose for that?

Click pics to enlarge

 
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did it stop running when you sat on it, or only when you put the kickstand up?
 
as soon as i put my weight on it. it first started a couple days ago when i was riding it was puttering and then would stall. i'm thinking that hose is bent and not letting the fuel through so maybe the pressure of the seat pushing against the tank on that already bent hose was cutting the fuel off. unfortunately my battery was too low today to start it up after i got the kink out of the hose. It's on the tender for the night and i'll try starting it up again in the morning.
 
Well the problem is still happening. Today the bike won't start at all. It will try to turn over, and sometimes will fire up just for a few seconds then stop. I've got the batter charged up so it's not that. It's on the tender. The hose i was thinking about being the problem in my previous post can't be the issue because it's just the small hose for the reserve tank. I want to pull the spark plugs and replace them, but now i have to find a wrench to fit, it's an extremly tight fit to get to the four plugs on the Magna. I'm also thinking of putting in some seafoam to hopefully clean the jets out if thats the problem.

Also another strange thing. When i did get it to fire up a few times, the engine sounds normal and when you crank the throttle you get the normal engine sounds, yet the needle for the rpm's doesn't move at all, it just stays at 0. Whats up with that?
 
Johnny5 said:
Well the problem is still happening. Today the bike won't start at all. It will try to turn over, and sometimes will fire up just for a few seconds then stop. I've got the batter charged up so it's not that. It's on the tender. The hose i was thinking about being the problem in my previous post can't be the issue because it's just the small hose for the reserve tank. I want to pull the spark plugs and replace them, but now i have to find a wrench to fit, it's an extremly tight fit to get to the four plugs on the Magna. I'm also thinking of putting in some seafoam to hopefully clean the jets out if thats the problem.

Also another strange thing. When i did get it to fire up a few times, the engine sounds normal and when you crank the throttle you get the normal engine sounds, yet the needle for the rpm's doesn't move at all, it just stays at 0. Whats up with that?
Click to expand...

That sounds like a electrical issue…like a battery issue. I’ve seen batteries that are faulty cause issues like this.
 
Not to add to the complexity of possible issue but I had the same thing happen to a bike in which the tip over sensor was tripped. It would randomly start and die when I stopped. Turned out the tip over sensor was not mounted correctly and would die at weird times.
 
Ok this is the noobiest of questions.. but what size wrench do you need to pull bike sparkplugs? I have an 11/16 and a 5/8 and neither fit. My plugs are deep in a tunnel and in a really awkward place to get out and can't really see them well. I went to crappy tire today and bought a cheapo sparkplug wrench thinking it would fit but it didn't, and none of my ratchets do.

I also bought a can of seafoam and put some in the gas tank and i did start up with some choke but i still have the problem of 0 rpm's, even though the bike is running and sounds normal, it makes the vrooom sounds when you crank the throttle so i am really worried about letting the engine run like that, will it seize something, or already is? I'm really confused Is it an electrical thing with the rpm gauge itself maybe?

I'm on a limited budget with this bike and don't want to dump a fortune on it since i got it cheap and planning on a newer bike later this year so i'm taking it one step at a time trying the cheapest things first. When i do finally pull the plugs and replace those if that doesn't work i guess the next step would be a new battery. But mine seems fine. I have it on the tender and maintaining the green light. .. Stumped..
 
Johnny5 said:
Ok this is the noobiest of questions.. but what size wrench do you need to pull bike sparkplugs? I have an 11/16 and a 5/8 and neither fit. My plugs are deep in a tunnel and in a really awkward place to get out and can't really see them well. I went to crappy tire today and bought a cheapo sparkplug wrench thinking it would fit but it didn't, and none of my ratchets do.

I also bought a can of seafoam and put some in the gas tank and i did start up with some choke but i still have the problem of 0 rpm's, even though the bike is running and sounds normal, it makes the vrooom sounds when you crank the throttle so i am really worried about letting the engine run like that, will it seize something, or already is? I'm really confused Is it an electrical thing with the rpm gauge itself maybe?

I'm on a limited budget with this bike and don't want to dump a fortune on it since i got it cheap and planning on a newer bike later this year so i'm taking it one step at a time trying the cheapest things first. When i do finally pull the plugs and replace those if that doesn't work i guess the next step would be a new battery. But mine seems fine. I have it on the tender and maintaining the green light. .. Stumped..
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Not too sure about your '84 honda magna but for my ninja it came with its own special spark plug tool to pull it out. I think for every bike they have their spark plug pulling specialty tool?
 
I definetely plan on taking it to a shop if i can get it running. Rosey's too far to risk it, but there is another one 10 minutes from my house but i have no way to get it there. @Bweixz yeah i would imagine they do, my bike didn't have the tool kit when i bought it :(
 
+1 on the spark removal tool. Hopefully your bike's tool kit came with one.

Since your plugs sit in a tunnel (similar to my Ninja) remember to spray some compressed air into that tunnel prior to removing the plugs. This will remove any dirt and debris that can fall into the into the engine after the plugs are removed.


Sent from my iPhone using Tapatalk
 
00ninja said:
+1 on the spark removal tool. Hopefully your bike's tool kit came with one.
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Unfortunately i didn't get the tool kit when i bought the bike. The seller didn't have it so i guess it was lost over the years as the bike changed hands. I Guess i will have to look to ebay for one, just further complicating.. delaying things.. frustrating.. :/
 
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