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If it was spark to be worried about wouldn't the problem be always instead of intermittent
The advice to inspect your plugs wasnt about spark but you can diagnose rich/lean conditions by plug appearance
 

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Super Moderator "Loose Nut" - Houston, Texas
2001 Vstar 1100 Classic (sold), 2006 HD Electra Glide Ultra Classic
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Possible causes from description, this is where I would start.

1. Air leak between carb and head, carb boots.

2. Float set too low for consistent fuel flow, or fuel flow issue, fuel filter.

3. Carb sync way off.
 
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The plug in the photo looked good to me. Do you know which jets were changed and to what size? If only the mains were changed, that could explain why it runs fine at idle and light throttle...
 

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you have a blockage in the main jets, something broke loose and is blocking one of the small holes , you can either clean it yourself or take it back to the guy who did the work. Best way to clean is with the wire from a twist tie in every little hole of the jets.
 

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This isn't another case of hitting the rev limiter is it? Does it only happen at high RPM and accelerating hard?
 

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Discussion Starter #26
Lesblank and Jspree are the carb experts. I will say I had a similar problem after tearing mine down to adjust the valve tappets. After checking, I found one side of the inlet air box had apparently slipped off the rear carb intake and I failed to catch it when I tightened the clamps. Re-seated it and problem was fixed. You might check yours... good luck. I'm sure the guys here will help you sort it out.
Is it common for them to just slip off over time because it was not doing this issue for a while after I got it back frome the carb clean and nothing has been touched to change it so do they just come off sometimes? There's no way they are cracking less than a year old right? tomorrow I can pull the tank and check it out but isn't there anything else that it could be?
 

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Discussion Starter #27
Is it common for them to just slip off over time because it was not doing this issue for a while after I got it back frome the carb clean and nothing has been touched to change it so do they just come off sometimes? There's no way they are cracking less than a year old right? tomorrow I can pull the tank and check it out but isn't there anything else that it could be?
Definitely not the rev limiter happens at mid throttle sometimes
 

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If something broke loose in his blocking a main jet would that be intermittent?
It means either they didn't do a good job of cleaning or they didn't flush the fuel lines good and change the fuel filter. As for the airbox , getting in a hurry and not making sure they are seated correctly before tightening the clamps will allow them to slip. also the reason I harp on air leaks is it only has an o'ring to seal the manifold to the head, most mechanics will put this on dry ( I use a tiny bit sealant) and they don't use a new o'ring and use the one that has been crushed and heated up. Then you don't know how well they sync'ed the carbs. It is very simple and you can make a very simple tool to do this. BPounds made a great one on here .
You will learn as you work with this bike all it is , is a big lawnmower engine , very simple and easy to work on. The biggest problem is rushing things and not taking your time. If you decide to take the carb apart, take phone pictures it will help you learn it and make it easier to put back together.
 

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Discussion Starter #30
Possible causes from description, this is where I would start.

1. Air leak between carb and head, carb boots.

2. Float set too low for consistent fuel flow, or fuel flow issue, fuel filter.

3. Carb sync way off.
Someone on here said something about making a carb sync tool how do I go about doing that?
 

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Ok, read down a little in this and you will see some pictures and you will see the tool BPounds made

 

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Discussion Starter #32
104340
so I got this finally in the mail will test that out soon but also I have some more info I am hoping helps out I checked my air filter and it's definitely wet so I tried running my bike without the filter and could barely make it down my road got to the stop sign and it stalled seems like the problem was worse so does that make any more sense that it's sucking too much air? I was thinking that the wet filter meant that I was running rich bc of the jets so I thought that getting more air might even things out but it made it worse! Am I way off here or what? AND AGAIN THANK YOU ALL FOR YOUR HELP!!!
Ok, read down a little in this and you will see some pictures and you will see the tool BPounds made

Ok
 

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Looking at your plug (that thing is lean) and symptoms, i really think you probably have a vacuum leak somewhere.

"The more you open your throttle the more vacuum you are creating in your carburetor venturi and your intake manifold. When you are operating at higher RPM any unmetered air leaks into your system can become more obvious.
Unmetered air is air that is getting into your system after the fuel has been delivered. If you have unmetered air getting into your system between the butterfly of the carburetor and the cylinder head this will create a lean condition."

You can do the carb cleaner test sitting at idle in the garage. just let it idle and spray around the carb boots and vacuum hoses. !! Have a fire extinguisher nearby...just in case !! No need to douse it.
Listen for a change in rpm...stutter, accel etc. You can also use an unlit propane torch...just gas the same areas...seems a bit more scary than carb cleaner but doesn't soak your engine and hoses with rubber destroying liquid.
 

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Ok, I tell about this too much on the forum. I'm sure others are tired of reading it, but.......
I know you said you drained your tank and replaced gas, however, the problem could be the gas tank itself. Last year, my son bought a barely used V-star 1300. Bike was in great shape but the liner inside the gas tank had deteriorated from old gas sitting in it for a long time. The bike acted exactly like you are describing. We did not discover the problem until the second time we removed and drained the fuel tank. Not saying this is you issue, but may be worth a look if the problem persists.
 

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Discussion Starter #35
Looking at your plug (that thing is lean) and symptoms, i really think you probably have a vacuum leak somewhere.

"The more you open your throttle the more vacuum you are creating in your carburetor venturi and your intake manifold. When you are operating at higher RPM any unmetered air leaks into your system can become more obvious.
Unmetered air is air that is getting into your system after the fuel has been delivered. If you have unmetered air getting into your system between the butterfly of the carburetor and the cylinder head this will create a lean condition."

You can do the carb cleaner test sitting at idle in the garage. just let it idle and spray around the carb boots and vacuum hoses. !! Have a fire extinguisher nearby...just in case !! No need to douse it.
Listen for a change in rpm...stutter, accel etc. You can also use an unlit propane torch...just gas the same areas...seems a bit more scary than carb cleaner but doesn't soak your engine and hoses with rubber destroying liquid.
Ok but this is a non rpm based problem like doesnt happen all the time sometimes I can make it all the way to 4th gear before it happens sometimes it happens as I'm taking off from an intersection and by"it happens" I mean the exact same problem as an unmetered air leak because I've had that before which is why I've changed the manifolds and the gaskets and the boot on top of the carb? I really don't think it's that and don't want to explode or catch on fire to test it is there another way to test it or another idea how to fix a problem a different way? If not I'll definitely do it just like to have a good risk reward ratio!
 

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Discussion Starter #36
Ok, I tell about this too much on the forum. I'm sure others are tired of reading it, but.......
I know you said you drained your tank and replaced gas, however, the problem could be the gas tank itself. Last year, my son bought a barely used V-star 1300. Bike was in great shape but the liner inside the gas tank had deteriorated from old gas sitting in it for a long time. The bike acted exactly like you are describing. We did not discover the problem until the second time we removed and drained the fuel tank. Not saying this is you issue, but may be worth a look if the problem persists.
Ok thanks this is kind of more of a sudden thing it was running fine and then just started doing that I thought I ran out of gas got to the gas station and it was half a tank?!
 

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because it was not doing this issue for a while after I got it back frome the carb clean
Just some thoughts:
  • Your recent comment above would suggest to me that the problem is not related to carbs being re-jetted
  • I myself wouldnt put to much weight on plug appearance UNLESS they were new with re-jetting but it would help to see the plug looking straight at the electrode. Carefully read the chart attached to help judge condition
  • I would recommend removing the air filter housing and air inlet duct to the air inlet box and do a full 360 deg exam of all joints entering and leaving the carbs, and the intake boots with bright lighting. Make sure everything is fully seated and tightly clamped. And yes, I have heard of some new after market intake boots failing after only a short period. Also make sure all your vacuum lines and caps are in place. What you are describing sounds very much like what I experienced when an inlet box boot wasnt seated and seriously unbalanced the carbs.
  • The fact this came on suddenly when the bike was running ok suggests something shifted, a jet plugged, or a component failed or is failing. Do make sure you have good spark to each cylinder.
  • 104356
104357
 

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Just some thoughts:
  • Your recent comment above would suggest to me that the problem is not related to carbs being re-jetted
  • I myself wouldnt put to much weight on plug appearance UNLESS they were new with re-jetting but it would help to see the plug looking straight at the electrode. Carefully read the chart attached to help judge condition
  • I would recommend removing the air filter housing and air inlet duct to the air inlet box and do a full 360 deg exam of all joints entering and leaving the carbs, and the intake boots with bright lighting. Make sure everything is fully seated and tightly clamped. And yes, I have heard of some new after market intake boots failing after only a short period. Also make sure all your vacuum lines and caps are in place. What you are describing sounds very much like what I experienced when an inlet box boot wasnt seated and seriously unbalanced the carbs.
  • The fact this came on suddenly when the bike was running ok suggests something shifted, a jet plugged, or a component failed or is failing. Do make sure you have good spark to each cylinder.
  • View attachment 104356
View attachment 104357
Not that this will help the OP, but that chart makes me want to ask a question. I've heard of running rich or lean but I've never before heard of running hot or cold. What exactly does it mean to run hot, to run cold? What would be the symptoms of those conditions? Can damage result from running in either of those conditions?
 

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What exactly does it mean to run hot, to run cold?
Spark plugs produce a different spark depending on how they made. Some have a hotter spark , some have a colder spark. This is why you use the spark plug that the engineers design the engine for. Running too hot a plug will cause burning on the valves and can also cause pre-ignition, if it is too cold it will not fully ignite the fuel causing excessive fouling of the plugs
 

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Discussion Starter #40
Spark plugs produce a different spark depending on how they made. Some have a hotter spark , some have a colder spark. This is why you use the spark plug that the engineers design the engine for. Running too hot a plug will cause burning on the valves and can also cause pre-ignition, if it is too cold it will not fully ignite the fuel causing excessive fouling of the plugs
 
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