Yamaha Starbike Forum banner

1 - 20 of 40 Posts

·
Registered
Joined
·
74 Posts
Discussion Starter #1 (Edited)
Since I picked it up last year, it has always started easily. Pepcock on. Full Choke. Key on. Neutral, Clutch, Just a bit of throttle, and hit the starter. Vrrrrrooom!

Now however, the starter cranks and cranks but it won't catch. After a while, I do get a strong smell of gas. Yesterday it took 5-7 minutes of cranking before it finally started. Then I rode it to work (~45 minutes). Almost the same thing coming home.

** I forgot to mention, that it has back fired a couple times during the cranking-but-not-starting phase. **

I'm a relative novice under the hood (so to speak), so I'm open to suggestions.

Bad Gas? I'm about 40 miles into this tank.

Did I get water somewhere I shouldn't last time I washed it? No, I don't use a power washer, and although it does get wet, I don't focus the hose on the engine.

This just seems kind of sudden.

Ideas?
-PH
 

·
Registered
Joined
·
1,052 Posts
** Check all electrical connection & grounds to make sure they are good & tight.

** Check you battery to make sure it is putting out the voltage needed.

** If you are worried about this tank of gas, drain it and pour fresh. (You can save that "bad" gas for your lawn mower. At least that is what I did.)

** Check you air filter. Make sure you did not suck something into it. and it is blocking the intake.

** Check you spark. It is strong, weak or ... nonexistent?

Those are just the first thoughts that popped into my head.
 

·
Registered
Joined
·
5,627 Posts
Couple things: how has your weather been? If its pretty warm out you dont need to pull the choke out all the way on a cold bike - maybe halfway. If your bike is jetted a little rich, pulling the choke out all the way when its 90 out might be flooding the engine.

how old is your battery? the electronic ignition has a voltage level, below which it will not fire the plugs. As the battery slowly ages some grey day you will crank your bike, and since the battery has been slowly degrading, it will sound normal... maybe a little slow, but the plugs wont fire. Sometimes if you crank it for a few seconds then let off the starter, the voltage comes up while the flywheel is still spinning and it will start. If you have a volt meter check your battery voltage, and check it while you are cranking the starter. If the battery is weak you can push start the bike (about 10mph down a hill in neutral, then clutch in and kick it up into 2nd gear, clutch out and off you go). If the bike will push / coast start easily then definitely need a new battery.

If you are using 10% ethanol gas then a little bit of water in the tank will get absorbed and wont cause any problems.

if you are smelling gas it is probably flooding - but check the overflow tube between the cylinders just on top of the right side of the engine case to make sure gas is not pouring out (stuck float bowl).

The fact that the bike runs ok once it starts points to either the battery being weak, or something is not right with the choke (or you dont need it on all the way).

Running some Seafoam through the gas tank can only help.

BTW, dont crank your starter for more than 10 seconds at a time, then let it sit for a minute. If it doesnt start after ten seconds its not going to, and cranking the starter longer will cook it like you would not believe. If it smells like gas (flooding) push the choke back in all the way the next time (after a minute for the starter to cool down).
 

·
Registered
Joined
·
5,627 Posts
One other thought - check your plugs -if they are all fouled out black the bike will be very hard to start.
 

·
Registered
Joined
·
359 Posts
Just want to add that in over two years of riding the 650 I have never had to give it "just a bit of throttle" to start it... seems to me I read on here somewhere that this is a no-no.

Glen
Focus On Newfoundland
 

·
Registered
Joined
·
5,627 Posts
... riding the 650 I have never had to give it "just a bit of throttle" to start it... seems to me I read on here somewhere that this is a no-no....
good catch, I missed that - keep the throttle off while cranking it...

on the 650 you can give it just a bit when it fires. On the 1100 if you give it throttle while the starter clutch is still engaged it will back spin the starter and blow the clutch bearings into metal confetti!

Times like this I wish we could step into a transporter and beam over to your garage with tool box in hand...
 

·
Registered
Joined
·
74 Posts
Discussion Starter #8
Times like this I wish we could step into a transporter and beam over to your garage with tool box in hand...

Ditto! I got a fridge of beer waiting for ya! I drained the old fuel and put in some new “Plus” along with some Seafoam. Still no go.

Plugs?




Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
5,627 Posts
usually when I ride home after work, the bike has been sitting in the sun all afternoon and I dont need any choke to start the bike. Its not 'running' warm from 8 hours earlier.

Definitely pulls the plugs and have a look.

this is a good time to say to everone, if you dont have a torque wrench, then get one before you put the plugs back in. Motorcycles have almost all aluminum heads and engine blocks, and its really easy to strip a thread out going by feel. Aluminum has no wrench 'give' or feel to it, like steel. It just strips if you over torque it.
 

·
Registered
Joined
·
74 Posts
Discussion Starter #10
usually when I ride home after work, the bike has been sitting in the sun all afternoon and I dont need any choke to start the bike. Its not 'running' warm from 8 hours earlier.



Definitely pulls the plugs and have a look.


Not too bad... IMG_0427.JPG


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
5,627 Posts
insulator looks good

gap and electrode center look worn - gap might be open a bit, but not enough to keep from starting.
 

·
Registered
Joined
·
5,627 Posts
can you get your hands on a volt meter and watch the battery voltage while you crank the starter?

even a $10 meter from walmart or harbor freight is good enough
 

·
Registered
Joined
·
5,627 Posts
if you dont have a volt meter plan B is push it down a bit of a hill (sloping driveway) while you are sitting on it, and see if it starts right up when you let the clutch out in 2nd gear? (dont forget to turn the key on and the kill switch to live)

the fact that the bike runs means your ignition and fuel supply is good, something is going sour when you are cranking it over with the starter.

If it starts right up when you coast/push start it, dont freak out - just pull the clutch back in and let it run.
 

·
Registered
Joined
·
74 Posts
Discussion Starter #14
can you get your hands on a volt meter and watch the battery voltage while you crank the starter?

even a $10 meter from walmart or harbor freight is good enough


IMG_0428.JPG

Here is the other plug. Also not too bad.

When I bought it, the dealer dropped in a new battery; that was about a year ago.

Where should I place the probes to check the voltage of the battery while cranking? Sorry: I’m a Noobe here but willing to learn!



Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
5,627 Posts
right across the battery terminals, meter set to DC Volts ( a scale 15 V or higher)

sometimes it looks like a V with a flat line

AC volts would be V~

make sure you have the probes in the Common and VOLTS/OHM jacks

if you put the probes in the AMPS jack it will blow the fuse out of the meter.
 

·
Registered
Joined
·
74 Posts
Discussion Starter #16
right across the battery terminals, meter set to DC Volts ( a scale 15 V or higher)



sometimes it looks like a V with a flat line



AC volts would be V~



make sure you have the probes in the Common and VOLTS/OHM jacks



if you put the probes in the AMPS jack it will blow the fuse out of the meter.


IT’S ALIVE!!!

I tried jump starting it in 2nd a couple of times. It was very close to starting. Then I put it in neutral and hit the starter. It backfired and started.

It’s very lumpy; not as smooth as it was.

At least I can try this in the AM to get it to the shop. Nothing worse then having it come in on a flatbed.

I’m taking bets what the shop is going to do. Replace the plugs? Carb clean?

Thanks to all that lent a hand during my real-time debugging session!


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
5,627 Posts
very nice!

I assume you meant push starting it. Jumping it from your car with jumper cables would be another option if the battery has gotten weak.

Anticipating your next question I just went out and took the cover off my battery, and 'Fluked' it while starting.

My battery is 3 years old and getting a bit soft. It was 12.8V before I cranked it, and it dropped down to about 10V and it started right up (started too fast really to get a clean voltage reading on a digital meter).

so the bike needs at least 10V while cranking for the ignition module to fire the plugs.

I shut the bike off immediately and my battery only came back up to 12V, so mine is getting soft and will need to be replaced soon. When I ride the bike a few miles it charges back up, so I know my alternator and regulator is working correctly.

Taking the bike to a shop is a good idea. If you have a little longer hill to let it roll down in neutral to get up to 10mph or more before kicking up into 2nd gear, it will have more inertia to spin the engine.

It could still be bad gas gunked up your carbs - something like seafoam might clear it out.

Its all a question of how much you want to work on it, or whether you would rather have a MC mechanic check it out. One of the trade offs for doing your own work - if you ride the bike a few miles away and it quits, because something is intermittent, then you have to get a trailer to get the bike back home.

either way, its all good.
 

·
Registered
Joined
·
74 Posts
Discussion Starter #18
very nice!



I assume you meant push starting it. Jumping it from your car with jumper cables would be another option if the battery has gotten weak.



Anticipating your next question I just went out and took the cover off my battery, and 'Fluked' it while starting.



My battery is 3 years old and getting a bit soft. It was 12.8V before I cranked it, and it dropped down to about 10V and it started right up (started too fast really to get a clean voltage reading on a digital meter).



so the bike needs at least 10V while cranking for the ignition module to fire the plugs.



I shut the bike off immediately and my battery only came back up to 12V, so mine is getting soft and will need to be replaced soon. When I ride the bike a few miles it charges back up, so I know my alternator and regulator is working correctly.



Taking the bike to a shop is a good idea. If you have a little longer hill to let it roll down in neutral to get up to 10mph or more before kicking up into 2nd gear, it will have more inertia to spin the engine.



It could still be bad gas gunked up your carbs - something like seafoam might clear it out.



Its all a question of how much you want to work on it, or whether you would rather have a MC mechanic check it out.



either way, its all good.


Thanks! Yep, the first task was to replace the cheap regular no-name-gas-station gas that I had previously put in it, with some Sunoco Plus grade and 4 oz of seafoam. I’m going to let it run for a while to circulate the seafoam in the carbs.

In the AM I’ll get it to the shop.

Dumb Question: does the bike have an alternator? Ie: does it charge the battery while running like a car?


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
5,627 Posts
yes, and its very RPM dependant because its pretty small.

Just idling it might not charge the battery up much. when you rev the engine to 2 to 3k rpm it really starts to kick in.

If you put a meter on your battery while its running you can see this.

Once the battery has charged back up (after you take it for a ride for a few miles) it should be around 12.8V with the engine off.

These bikes have an alternator and a proper voltage regulator that keeps the battery from overcharging on a long ride.
 

·
Registered
Joined
·
5,627 Posts
I feel like I need to go take my bike for a ride now. I put regular ethanol free gas in it for the first time this week, and its running really great. When I get 220 miles on the odo I will see if the MPGs went up too.
 
1 - 20 of 40 Posts
Top