starter stopping after one turn.

Initially atleast.

When I go to start the bike when leaving work, sits for about 10-12 hours, the starter will turn once, and stop. With breaks in between of course, it happens once or twice before it finally keeps spinning and starts. Any ideas?

Heat index here is between 100-110 lately, if that matters.

The starter is still engaged when it stops, it just won't spin, and it won't let off until I let go of the button.

 

Sounds like the starter clutch, what oil you running ?

 

If it's the starter clutch, the starter will keep spinning, and will make a nasty grinding noise, but won't turn the motor.

If the starter is not spinning, I'd suspect brushes or a dirty commutator.

 

You put a different interpretation on the description.

 

Yeah... I'm not sure exactly what's he's describing. Between the two, I think we have most possibilities covered. The "...still engaged..." does sound like he's talking about the starter clutch letting go.

 

Disconnect the battery.
Easy.
Remove the Lead from the Starter's Power Post.
Easy.
Undo the two Bolts and pull the Starter.
Easy.
Undo the two long Bolts on the Starter.
Easy
Duct Tape the Planetary-end to the Motor Casing so it don't fall all apart.
Not too difficult.
Pull-away the Aluminum Case which covers the electrical end, a little bit ... and peer inside at the Commutator and Brushes.
Uncomplicated.
Use a trigger-pull Squirt Bottle that has a Spray ~ Stream option, filled with Isopropyl Alcohol ... set to Stream ... and Douche-out the Electrical-end.
Do the Commutator
Brushes
Inside the Cover.

Look at the Brushes after they are Cleaned and you can see them with a flashlight.

The should be OK.

After the Douche-out; put everything back to normal.
See what happens.

 

I'm on the brush bandwagon. It's simple and easy to access the starter motor to just take it off mess around with indoors (I rebuilt mine while living in an apartment) and while you have the starter in hand to check the brushes ya could take a pencil eraser to the contacts on the rotor. Either of these could cause the symptoms described (as I too understood them).

Since it cranks and fires strong (I assume) when it feels like it there's no cause to suspect battery.

It's vaguely possible there is something hinky with the starter clutch like a chunk of something that catches in there and locks everything up then falls away but I really doubt that. It would prolly blow a fuse trying, fall away and end up in the sump never to bother again or at least it would present other symptoms causing the OP to tell us about.

I'm prone to suggest the simplest to fix and/or most common problems first so yeah, starter motor maintenance. If I ask when the last time it was inspected and ya can't tell me, especially cuz the PO didn't tell YOU then it IS due.

 

I'd use the usual trouble shooting manner of repairing or replacing the
(1) most logical part
(2) easiest part
(3) the cheapest part
before getting into the starter clutch.

1 last thing, you are certain that your floats are holding and that the petcock isn't leaking by....right? Because if they were there would be a chance that 1 cylinder or more could be flooded and hydraulicly locking up the engine.......
Just a thought.

I'd start by checking the battery and the starter electrical system out 1st.

 

By engaged I mean the starter is still attached to the engine and seems to be applying torque.

In car terms the bendix is still sticking out and engaged to the flywheel, and disengages when I let go of the button.

Hvnbnd, I was initially worried this was more of a mechanical issue with the motor. It is not tuned, or synched yet. My drive to work is short and I don't have to go above 4000 rpm, so I figured its okay to put some miles on it, especially so I can flush the oil a bit. until I get everything to tune it I figured ide make sure everything else is in good shape.

The float levels were adjusted to stop the carbs from overflowing, probably close but not within specs.

The petcock was holding just fine as of last week when i pulled the tank. But if gas was still flowing to the carbs wouldn't it be leaking out the airbox and not into the engine?

 

Nope. Fills up the motor first; then the now overfilled crankcase starts pumping its gas/oil mixture through the breather into the airbox. Gas won't run uphill.

Did you CHANGE the oil (and filter) yet?

 

Yes I did.

Before when the needles weren't seating properly and I primed the carbs gas would overflow out a tube on the airbox.... so now I'm confused, fitz.

 

I just changed my bike with Motorcycle 10w40 this past week, it was all Walmart had at 11:30pm the night I was out that way.

The starter worked fine for a week or so, and then yesterday it makes 1 full turn and then a weird grinding/slipping sound, if I release and hit the starter again it will repeat and usually after 3 or 4 tries it finally starts normally.

With the high heat, could the oil be not the right viscosity and causing this to slip like mentioned above?

Should I change it to 20w50 soonest? or just be careful on hot days?

Thanks,

BTC

 

Did you get motorcycle oil?

 

Yes, I can't remember the brand, but Walmart only carried 2 brands, and I picked 10w40 without thinking, they had a 20w50.

Since I won't be shopping so late next time, I can visit one of the other automotive stores that carries a better choice of MC oils.

BTC

 

Don't run synthetic.
The starter clutch is not like a car, it works with friction & rollers.

 

I made sure it wasn't synthetic. I am pretty sure gas leaked back into the oil reserve tho, on the side stand it shows oil up past the glass...

My neighbor left it on Prime not knowing better. Guess I get to buy more oil again...

Need to figure out which float/needle isn't sealing well too I guess.

BTC

 

-Pull the carbs, and check your float levels. In the course of doing that, you'll discover which one isn't shutting off properly.

-IMMEDIATELY change the oil; don't run it with gas in the oil. Be sure you're not overfilling; the level should be checked with the bike on the centerstand or held vertically, and after the bike has been shut off for at least 10 minutes.

As long as you're using MOTORCYCLE oil, you should be fine on oil choices, although I'd use 20W50 (or 20W40 if you can find it) in the summertime.

 

I run 20-50 and just don't ride when it's too cold..

The oil should be checked "with the bike on the centerstand or held vertically, and after the bike has been shut off for at least 10 minutes." (as Fitz says)

If your petcock has to be on prime to run then you need to do something with it. (fix or replace it) I went with a manual petcock.... works good as long as I remember to shut it off and turn it on.
Before pulling carbs try taping on the float bowls and see if one might be stuck.

 

It didn't need to be on Prime, the vacuum pitcock works pretty good. We let it sit for a few days off the bike with gas in it and I never saw it drip, so I am pretty sure that part is good. Unfortunately if one of the floats isn't perfect, while it is running, it's potentially seeping into the oil reserve.

I really hate pulling the carbs off the bike, but guess I'll be doing that this weekend.

BTC

 

Actually, no it's not. If the float isn't shutting off while it's running, then that cylinder will simply run too rich (or roughly, if it's "dumping" enough fuel.)

It's when the engine's OFF that fuel can find its way into the crankcase. ONE float bowls' worth of "extra" gas isn't going to overfill your crankcase. Either you've had the problem for a while, going unnoticed, or your petcock is not shutting off reliably in addition to the sticky float.

 

Deleted - Started new thread.

 

DUDE. Don't hijack Rudy's thread.

I will give you solid answers to all 6 of your questions and some advice as well.

As soon as you start your own thread. Call it "fuel supply questions" so "petcock" doesn't get edited.

Your issues are similar but different from what Rudy (the "OP" or Original Poster) is going through. Don't drag him off track.

Just "copy/paste" your last posting if you want; and we'll go from there.

Thx

 

Well i gave the crankcase a smell and i do believe i smell gas, so im going to go ahead and leave it parked until i get all the parts and tools to go ahead and do EVERYTHING it needs.

Ill assume for now that its a problem with fuel flowing into the combustion chamber, and if it still hangs up after i get the intake aspect of the engine completely set right, ill pull the starter and check it out.

Ill go ahead and bump this topic after its road ready and ridden for a couple days.

thanks guys.

 

Don't be shy about asking questions if any arise in the process.