Topic: 'flat part' on starter... oops, maybe it's the charging system!

[Frankenkit]

So I got to bring my bike home, but in accordance with the "one more thing" mantra, there's a 'flat spot' in my starter according to my mechanic.  (3/4 of the time, I hit the button and without even hearing the starter, she fires up... but that 1/4 of the time, it spins reeeaaaaallll slow like the battery's dying) 

Wondering how long I can ride my bike without having to take the starter out to be rebuilt, if I'm going to damage my starter clutch or anything riding it like this (i.e putting off the repair until winter if I can get away with it...) 

[Gordon]

Two words:

Kick start

[Frankenkit]

ADDENDUM:
Due to Gordon, I'm obliged to supplement my post with this:
no kick start!!!   

 

[TwoTired]

Sign for Gordon to wear on his back today"

"KICK ME"


 

[scondon]

 Can you check the voltage on your battery?  After a regular ride, let the bike sit for a couple hours and check voltage with key off, then with key on. For me the "lagging" starter is almost always an indication that the fluid levels in the battery have dropped, the battery is nearing replacement, or the charging system is in need of attention.

[Frankenkit]

Charging system is great, maybe a touch on the high side, battery is new and at full charge.  The problem seems worse when the bike is warm.  I read TwoTired's post on rebuilding a starter and it sounded about exactly like the problems I'm having... just need to figure out how long I can get along without a rebuild...

[Gordon]

Two words:

Push start...

[TwoTired]

....But about the starter....  Much depends on what the trouble actually is.   Since I haven't been inside a 650 and assuming it work in similar fashion to the 550...

The described symptoms sound like the motor isn't getting enough power from the battery.  The symptoms are similar when there is a weak battery, too little starter drain, or too high a starter drain.
Could be the starter motor has failing brushes, that aren't making contact with the commutator consistently.  Possibly due to the brushes being worn too short, sticking in the brush holder, or a glaze has developed on the commutator.
Another possibility is that the armature bearings have worn and are allowing the armature to contact the frame.  This would drag down the battery voltage and make a new battery behave as a failed/failing one.

If your plan is to replace the stater motor, using it until it is replaced will cause no harm to the motor until this repair work is performed, unless the stater is making excessive drain on the battery, which can shorten it's life.

If you plan to repair the existing starter motor, the sooner you address the problem the higher the expectations of a successful repair to it.

If the bearings are worn out, then you could probably tell by monitoring the battery voltage.  A slow start event will be marked by a much deeper voltage dip than a brisk start.  You can use the kill switch to activate starter without engine start.  Suspect this cause, if your battery runs down much quicker than you expect it should.

A commutator/brushes issue will show the battery voltage to be actually higher than a normal start event due to the commutator "disconnecting" itself from the battery.
Worn brushes don't grow back.  Some brush holder mechanisms lose their holding capabilities an then allow the spring the pushes on the brush, to contact the commutator and gouge the surface.  If this occurs too long, you have to replace the brush spring, too, and possibly the commutator (meaning the entire starter, in most cases).
Stuck brush holders have a possibility of freeing them selves with heat and vibration.  Or, they simply remain unreliable.  Or, they eventually stop all contact with the commutator and the motor ceases to function completely.

An insulative glaze on the commutator, sometimes wears off with consistent use.  But, this can test your patience.

The starter comes out in about 10-15 minutes of work on the 550.

Cheers,

[paulages]

erin- i have a starter if you need one.

[Frankenkit]

sent ya a pm

[Frankenkit]

OK, not the starter: put the Paul's starter in yesterday (with new plugs, just b/c I was testing a theory on a misfire on 2) and she fired right up, the new plugs seemed to solve the missing problem, and all was right with the world.  The battery was dead, but I figured that was because I'd been railing on my starter, hoping it'd get started for me that morning.  Charged the battery for a bit, then it started right up...

until I went for my first 'round town ride, in which about 10 miles down the road, the bike died and wouldn't start again.  (might've choked it out, I  was starting again on an up-hill intersection and my PIC's bike is so loud I can't hear mine over it...)

Anyway, we managed to push-start it, rode another 10 or so miles through suburban cul-du-sac mazes until it felt like high time to get home.

The problem now is:
If it's not the starter, it's likely the charging system.  I tested voltage @ the battery and it was 15v... Raven said that was a bit high, could be my reg/rect going, but I'm not sure how that would affect my charging...  My ineptitude knows no bounds when it comes to electrical this-and-that, so any help would be great.  Thanks!

[TwoTired]

Do you have a multimeter?  What brand and model number?  Can you post a picture of it's control knobs/switches?

When I search for a wire diagram for your bike.  What year and model should I look to use?

15V is too high.  Indicating a vreg issue.  But, the vreg can fail when the alternator rotor becomes low resistance, over-stressing the regulator.
Check the rotor resistance. It should be around 6.8 ohms. (Subtract meter lead resistance from meter reading.)
If it's lower than that... well, you've got some swearing to do.

Cheers,

[eurban]

Certainly you should continue with the checking of your charging system.  I wonder if your voltmeter readings were accurate though? . . . In my brief stint with a 650 I experienced issues with the charging system and the starter. The starter would operate normally when cold but if I, for instance, stalled the bike out in traffic, it would often not be able to turn over the engine.  A bit of waiting and it would crank over fine. Does this describe your issue? Fixing the charging system (in my case replacing the rotor) did not fix the problems with the starter.   I never did fix the starter but over the years since have seen this same problem mentioned a number of times.  Seems to be a very common 650 thing.  Solutions offered were related to the starter brushes and carefull cleaning of the wiring and connections to the starter.  I have seen starter brushes for the 650 offered on line in the past but don't have a link for you. (edit Partsnmore has them in case you find the need)  I would think that it is possible that Paul's starter is suffering from the same issues that your orginal one was, particularly if this is very common 650 thing.  Your wiring could also still be suspect as could your solenoid. 

[paulages]

I would think that it is possible that Paul's starter is suffering from the same issues that your orginal one was, particularly if this is very common 650 thing.  Your wiring could also still be suspect as could your solenoid. 

the starter i gave her was from a cb500. not sure what electrical issues unrelated to the starter motor itself could even effect it, unless something was causing the plates in the solenoid to no connect.

erin- i'll give it some thought, but if it's electrical you're in good hands with TT. the regulator/rectifier on those is solid state, so you don't have the ability to adjust it if it's overcharging the battery. didn't you also get that reg/rec from me?

[Frankenkit]

It doesn't want to start when cold, either.  I've charged the battery, and still after a few (immediate) starts, it'll eventually crank verrrry slowly, then not at all.  I'm going to be doing a thorough cleaning of connections, and start checking the charging system once I have some guidance... Should I disconnect the negative terminal from the battery first, before cleaning, or does it not matter?

TwoTired: My multimeter is a Knight K-810, bike is a 1980 CB650c.

I have a suspicion that there's a power drain while the bike isn't running, but I'm not sure how to check that, either.    


Paul: Didn't get a reg/rect from you, I got a pulse generator and coils from you... as far as I remember, but this has been kind of a long-running project...

[TwoTired]

OK.  The meter pic doesn't allow me to read the markings.  But, it looks to be adequate for the task at hand.

Let get right to the heart of it and check the rotor integrity.  On the R/R you'll find white and black wires that lead to the alternator.  (I'm using the wire diagram @  http://oldmanhonda.com/MC/WiringDiagrams/MCwiring.php#class  )
You're going to measure these wires and the resistance of the rotor with your meter.
Disconnect the wires (you don't want he R/R unit to affect the readings) and place the meter's probes on each one.  Set the function knob on the meter to the lowest resistance scale  (I think that's 400 ?).
Note the meter display results.
Now take the two probe end and place them together.  This is your test apparatus contribution to the reading which you must subtract from your measurement of the White and Black leads.

Report your results:___________

If you suspect constant drain.  You can test for this, too.

Again I can't read the meter function knob markings.  But, the specs on it say it can measure 20 A current.  You will have to use the black probe into the meter's black ring socket but move the red probe plug to the far right socket labeled (15A)?  I'm not sure. I can't read the printing very well.  The function Knob should be position in the DCA area (again I can't read the numbers)  Choose a number that is unlikely to be exceeded during the test.
About that.  Since your meter is only capable of 20A, never hit the starter button during the next test.  You could poof the meter with a starter draw of 150A.
With the meter configured, disconnect the POS battery terminal, and insert the meter lead as a bridge between the battery terminal and the cable lug, red lead to battery post, black lead to cable lug.

You can turn on the key switch and the meter will show you the current drain.  Note this number:___________
Turning the key switch off should display another number:  ____________

On the suspicion that your R/R is fried. Disconnect the White and Black alternator leads from the R/R again.  Note the meter reading: _________
Now disconnect the entire R/R from the bike wiring.  Note the meter reading: _________

Further action, will use the above readings to determine which branch to take for further troubleshooting.

Good luck!  If You need further clarification, ask.

Cheers,

[Frankenkit]

My battery's really low right now, should I take it to full charge before testing?

[TwoTired]

That would be desirable.  Particularly for the drain testing.   But, it is not necessary for the alternator rotor ohms reading.   The power for that test comes from the meter itself.

Cheers,

[paulages]

erin- the black wire he's referring to going to the field coil i've seen blue instead of black. i'm not sure what year the one i saw like that was-- '81 or '82 for sure (CV carb engine)-- but just know that if that's the case it's going the same place.

[bistromath]

Anybody think to check the starter solenoid?

[TwoTired]

Anybody think to check the starter solenoid?

Sure, but the report of 15V at the battery is NOT a starter solenoid issue.  Such a voltage can permanently damage a battery.  And, a damaged battery may not spin a starter properly.  When we have test data, we can determine if the charging system is buggaring the battery.  When both these system components are known good and reliable, and the starting problem persists, then we move on to solenoid, starter and connectivity issues.

But, that's just my plodding, boring, troubleshooting technique.

Cheers,

[Frankenkit]

Haven't had a chance to actually test this yet, spent the evening cleaning connections and installing my new throttle cables. Unrelated, I know, but I'm ADD like th...
...uh...

...whatever I was saying.

 

I figured clean connections would probably give better information.  In the process, I pulled the red wire heading from the positive batt. terminal to the main fuse.  The end that hooks to the battery is badly mangled (looks like a U with the ends of the 'U' corroded down to bare copper and chewed up as if by pliers. (?)  both connectors were pretty dirty, so I cleaned both and put a little dialectric grease on the negative (replacing the hookup on the positive) to further prevent corrosion.  Did the same on the little plugins for the R/R (both kind of dirty, but not obviously so, a couple spider nests between the fins of the R/R,  and dead spiders hanging out in the empty slots of the female couplers and around the main fuse) 

Should be interesting.

Strongly considering going with LED instrument lights to further cut down on system draw, even when I get my charging system figured out.

[martino1972]

did you check the fuses on the triple tree?? are the ends corroded???

[Buber]

Ok, a tip.
Kitsune, did you get the CB650 shop manual? There's a whole section on how to check the regulator/rectifier. Find it, read it , apply the test (easiest one, with the multimeter).

It will show if any of the diodes in teh assembly is shot.

Good luck!

[Hush]

Have yet to have this problem on my bike Kits but I'm only garage testing at present and starter is real good with engine firing even when battery very weak.
I have heard war stories of our 650's having charging problems but these bikes are way too rare here in NZ to get any local coroboration on that.
Reading your thread I was initially convinced your problem was a worn starter but that 15volts reading (if accurate) is a bit OTT.