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Discussion Starter #1 (Edited)
I have a V star 950 (2012), it takes two three tries or even more to start the engine and sometimes don't start at all(it do crank but sound like something is stuck), if the engine is hot (after riding). Then I have to wait a little bit and usually it starts after waiting 10mins or so. I have no problem starting in the morning or when engine is cold. Do anybody know the possible cause
Eric how is your bike behaving, is it the same like mine or is it don't like to start any time
 

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I have a V star 950 (2012), it takes two three tries or even more to start the engine and sometimes don't start at all(it do crank but sound like something is stuck), if the engine is hot (after riding). Then I have to wait a little bit and usually it starts after waiting 10mins or so. I have no problem starting in the morning or when engine is cold. Do anybody know the possible cause
Eric how is your bike behaving, is it the same like mine or is it don't like to start any time
Will it start with he gas cap off when it is hot? Could be a vapor lock issue due to the fuel tank not venting properly.
 

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Discussion Starter #3
I never had a vapor lock issue in my whole life, but yeah it may be the case. But with fuel injection chances are low. I will try with gas cap off (usually this happens with me at fuel station when i stop for refueling after ride).
When its hot, it don't crank properly (may be half crank n then stuck n all lights go off), not like no fuel when you keep cranking and engine don't start but it do crank.
 

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I never had a vapor lock issue in my whole life, but yeah it may be the case. But with fuel injection chances are low. I will try with gas cap off (usually this happens with me at fuel station when i stop for refueling after ride).
When its hot, it don't crank properly (may be half crank n then stuck n all lights go off), not like no fuel when you keep cranking and engine don't start but it do crank.
Actually the vapor lock I am talking about is fairly common on V Stars, has nothing to do with the fuel injection. Somehow usually after the gas tank has been moved or lifted, a vent gets pinched and the tank becomes under a vacuum causing the fuel pump to cavatate and not able to deliver fuel to the engine.

You situation sounds like something else. Like others suggested, put a volt meter on the battery when the engine is running, you should get 14.5 volts. Also see how far the battery voltage drops when you start.
 

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Discussion Starter #5
I tried with gas cap off but it didn't help. My battery is not very good but still it works fine if engine is not hot.
Battery readings are as follow.

before starting = 13.85V
1st try = Volt drops to 7.8 (after continuous crank 5s) but returns to 13.5 when I stop.
2nd try = Volt drops to 7.5, returns to 12.95 after I stop.
3rd try = Volt drops to 7.0, returns to 12.65 after I stop.

But if it starts Volt only drops to 10.5, not less than 10.
 

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I tried with gas cap off but it didn't help. My battery is not very good but still it works fine if engine is not hot.
Battery readings are as follow.

before starting = 13.85V
1st try = Volt drops to 7.8 (after continuous crank 5s) but returns to 13.5 when I stop.
2nd try = Volt drops to 7.5, returns to 12.95 after I stop.
3rd try = Volt drops to 7.0, returns to 12.65 after I stop.

But if it starts Volt only drops to 10.5, not less than 10.

During cranking the battery voltage should not drop below 10 volts for up to 20 seconds.

Are you saying during cranking that leads to a successful start, the voltage drops only to 10.5 during the crank? If so sounds like something is drawing the battery down, like a bad starter motor
 

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If the starter motor is stressed (it is having a really hard time spinning the motor), it will drop low also.

Basically the above proves it's not a loose connection.

Maybe oil, but I doubt it. Especially if it is in neutral when starting.
Besides the starter, I can only thing of having higher than normal compression.
 

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Just to isolate the problem, you might want to go to an auto-parts store and have them load test the battery just to make sure nothing flaky is going on, but I am guessing the starter is the issue.
 

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Discussion Starter #9
During cranking the battery voltage should not drop below 10 volts for up to 20 seconds.

Are you saying during cranking that leads to a successful start, the voltage drops only to 10.5 during the crank? If so sounds like something is drawing the battery down, like a bad starter motor
Yes if it starts in that case voltage doesn't drops less than 10V. I will check my battery at some store. It may be a starter motor but what makes me confuse is that it starts good in morning or whenever engine is not hot.
I thought about starting with new battery, if problem is not solved than start looking for something else but I also don't want new battery as its almost end of riding season here in Chicago.
 

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Discussion Starter #10
If the starter motor is stressed (it is having a really hard time spinning the motor), it will drop low also.

Basically the above proves it's not a loose connection.

Maybe oil, but I doubt it. Especially if it is in neutral when starting.
Besides the starter, I can only thing of having higher than normal compression.
What about Oil, it may be the case because I changed the oil n oil filter in April,2017. The oil filter was bad so I replaced the filter without draining oil except for what came out with filter, so I added some oil after installing new filter.
 

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I forgot you had the issue when it was hot only.

It shouldn't be the oil in this case, might be, probably a cheap check.

With it not functioning correctly hot, I think it would have to be the starter. It could have a short in it, that only makes contact when it is hot, all the wire windings in there.
Only way I can think of to be sure is to test current draw on it, when it's cold vs hot.
 

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I have not heard about this on Vstar bikes but its a common starter issue on Honda Goldwings. Starter gets full of carbon dust from the brushes wearing down and starts fine when its cold, cranks slow when its hot.

The reason the bike will not start when the battery is pulled down below 10V is the ignition and fuel injection systems are running off the battery, and will not fire the plugs or the injectors when the voltage drops too low. The starter will still crank (slower and slower at lower voltages) but the bike obviously will not run.

in this situation you can push start the bike, without the starter pulling the battery down it will run just fine being pushed and popped into gear.

If this always happened, hot or cold, then I would suspect the battery is old and weak.
 

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Discussion Starter #13
I have not heard about this on Vstar bikes but its a common starter issue on Honda Goldwings. Starter gets full of carbon dust from the brushes wearing down and starts fine when its cold, cranks slow when its hot.

The reason the bike will not start when the battery is pulled down below 10V is the ignition and fuel injection systems are running off the battery, and will not fire the plugs or the injectors when the voltage drops too low. The starter will still crank (slower and slower at lower voltages) but the bike obviously will not run.

in this situation you can push start the bike, without the starter pulling the battery down it will run just fine being pushed and popped into gear.

If this always happened, hot or cold, then I would suspect the battery is old and weak.
It only happens when bike is hot, engine starts fine when its cold. When hot it don't crank slow or keep cranking instead it just crank n stuck n crank then usually all lights of meter go off like no battery. It feels like something get short when its hot like patrickdk mentioned. Can it be coils (I have heard people having bad time with coils on Vstars). Do coils involved in starting or it may be a bad starter?
 

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Shouldn't be the coils, the coils supply the voltage to the spark plugs. If that was the issue, the bike would spin and spin, but not fire up, but yours won't spin properly.
 

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Discussion Starter #15
When cold my motorcycle draw 178Amps n fires on first try, when hot it draws 315Amps, cranks but feels like its struggling or something is stuck n then lights go off, then again try may be after 5mins it draws 278Amps n starts.. when engine running meter show current between 3 to 4 amps
So what you guys think the problem may be. any suggestions please
 

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It has to be the starter. The only reason for that is if the motor cannot spin. The would be due to the engine being locked up, but that isn't the case cause it starts when cold, and runs fine when hot.

If it was an AC unit, I would say the capacitor is bad on the motor :) But these are DC motors and don't use capacitors.
I have worked on many DC motors, but I don't have really any experience in DC motor troublshooting.
 

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I agree it still sounds like the starter - something is going on inside it when it gets hot. It should not draw twice as much current to start a hot engine.

Till you get it fixed i would recommend not cranking it when the motor is hot. That is a lot of current, it could be damaging wires - its basically a dead short on your battery. Batteries can explode when shorted.

if you need to hold off to get a new starter, or to pull this one off and rebuild it, you can push start your bike easily, esp if you always park it pointing down a bit of a hill (like down a driveway).

Turn the ignition key to run, kill switch to Live, bike in neutral, clutch in, sit on the bike and duck walk it up to about 5mph, kick it up into 2nd gear, let the clutch out and it will take off and go with a warm engine. If you can coast up a little faster (10mph) then even better.

only problem would be if you stall the bike where every direction is uphill, that would suck.
 

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Discussion Starter #18
I am thinking to take apart starter and maybe clean it or put new brushes but not now. I will wait for the winter because I know for me its gonna take some time to repair it and keep the bike running. If anyone has any video or reading material for changing/repairing a starter that would be appreciated.
Lately I have been doing this that when its hot, I wait for some time and then cranking the engine and it works for me.
 

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If you want to get an easy ideal of how push starting works, ride your bike up to about 30mph in 3rd gear, pull the clutch in and hit the kill switch so the engine stops.

Turn the switch back to run, and let the clutch out slowly. Its a lot simpler than it sounds.

Racing bikes dont have electric or kick starters, the are always push started.
 
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