Topic: The Ever-Popular CB650 bad charging 'issue', formerly hot start 'issue'

[Frankenkit]

It seems people have had problems with the 650's starter when their bikes get warm:
http://forums.sohc4.net/index.php?topic=42198.0
http://forums.sohc4.net/index.php?topic=11815.0
http://forums.sohc4.net/index.php?topic=39986.0

etc etc
(and not all of them are 650s, but...)
I switched my starters earlier- got a new one from Paulages, and that one does the same thing.  I'm not sure if his brushes were worn as well ( could be)

My question:
Obviously removing the starter is an easy, 10-15 minute job provided you get that little end gear's teeth to line up with everything else correctly.  BUT, how hard is it to replace those brushes in the starter (considering all skill levels, not just retired professionals) AND having done all that, will it actually remedy the problem?  Right now I just need to open the throttle a bit and she fires right up when hot, but occasionally this happens also when cold, and that can be a little tougher.
as referenced here: http://forums.sohc4.net/index.php?topic=37934.0 I tested all my electrics, etc, everything 'else' was fine...
...so for me, and the other 650 owners whose starter does weird stuff when hot, just looking for a condensed answer.
As it is now, I found a site http://www.dansmc.com/electric_starters.htm that more or less explained the matter of 'rebuilding' starters (only as far as springs, brushes, cleaning up and testing the commutator, etc goes) and found that (since I have a spare starter laying around with the same symptoms) it was relatively painless ($25 in parts- the o-rings, springs and brushes) to attempt this myself.  I'll report my success or failure, whichever.

[jonbuoy]

I don't own a 650 but hot starting problems may be due to a voltage drop through the starter solenoid, compression will be higher when the bikes hot meaning starters working harder and pulling more current.  My 10C

[Soos]

My father in law had this problem on his 550 yamaha, and bought a re-build kit off e-bay.
It wasn't too hard to do, and once done it started line a champ again.

Good luck!



l8r

[dusterdude]

kit,if there is an alternator/starter rebuilder in your area,they can handle the rebuild for you.

[martino1972]

i'll be watching the canary...............

[Frankenkit]

Alrighty.  Uploading pics now.  Got home from school and started tearing crap apart.  I decide since time is at a premium tonight, I'm just going to inspect and clean.

Brushes looked better than I expected them to.    There was still dirt and carbon (and all other manners of crap and corrosion) present, so that could still have been part of the problem.

The commutator (and brushes) had some kind of deep looking grooves to them, so I can figure that would impede their connectivity.  I used a fine sandpaper to polish them down to a smooth meeting surface (considering the length of the brushes, that seems alright.  I still have the other ones coming to the Honda shop 'just in case')
Springs are definitely fine, so I'll probably just return those to Honda.

Blasted some air through the mica gaps, made sure they were clean so carbon wouldn't be doing stuff it shouldn't.

Ok, pics:




Also cleaned and oiled the little shims present, just screwed things together so everything would be 'where it should be' until I can get at them, but noticed the shaft turned much more easily than it did before...

[TwoTired]

Check the free play between armature shaft and those end bearings, too.  There must be very little slop.
Also note whether there has been rotating contact between the armature and the field winding cores.

Cheers,

[Frankenkit]

Now, would that slop be reparable?  would the rotating contact be favorable or not?

[Really?]

Just wanna drop my 2 cents in here.  My suggestion may not even make a difference on these bikes (CB's).

Many 1st generation Yamaha Ventures have hot start problems.  In some cases, there is a problem with either the battery and/or starter.  Most of those issues were resolved by using thicker gauge battery cables (6ga to 4ga).  To add to it, many are also running 670 cranking amp maintenance free batteries in addition to the cable upgrade.

Many of those cables were about 20 years old before they got changed to.  They will corrode and create a resistance.  Even though they were replaced, the 4ga cables are what did the trick most of the time.

[Frankenkit]

I might be mistaken (I usually am, if I'm not sitting right in front of my bike...)  ...but aren't these thick braided cables?  I don't know a whole lot about electrics, but how would one go about switching from 6g to 4g?

[TwoTired]

Now, would that slop be reparable? 

Yes.  By replaceing the bearings

would the rotating contact be favorable or not?

Absolutely not.  As it effectively shunts major current from the battery, causing large drains and little current actually available for the motor to use for creating magnetic fields.

Cheers,

[Frankenkit]

Thanks for the clarification.  Hey, TT, I'm looking at the parts fiche from both the honda parts catalogue and my service manual, and I don't see any bearings that I really know of, unless they're synonymous with  the little thin shims I found at either end... 

[TwoTired]

Thanks for the clarification.  Hey, TT, I'm looking at the parts fiche from both the honda parts catalogue and my service manual, and I don't see any bearings that I really know of, unless they're synonymous with  the little thin shims I found at either end... 

Are your bearings bad?  Do you have armature to outer frame contact?

These bearings are also called bushings.  They are made of porous metal so they can hold lubrication oil for the life of the motor.  They are pressed into the motor end shells.   I doubt MC shops sells them separately.  When mine went bad, I found a shop and robbed the bearings out of starter for a Yamaha (Or was it Kawasaki?).
Anyway, the alternative is to take measurements and go to a bearing supply house.  They can look through their catalogs and suppliers offerings to find a match.  Or, get something close that a machinist can refine to fit.

Cheers,

[Frankenkit]

just asking so I know what to look for when I go into it.  Gotta keep my hands mostly clean (or at least not black) tonight yet, working in the operating room tomorrow and Friday, so right now it's just postulation until I can really get into it. 

The bushings looked largely unworn... so we'll see

[Hush]

Just a Kiwi angle on this Kits, last year my boats starter went bad and I lashed out $80 for new bushings and stuff and rebuilt my own starter, clever me eh!
Well short story long, this year same starter and yep she's poked again, disassembled and it had gone to Hell again in some green and furry way.
Just had the experts rebuild it ($247) and they did so many things I never would have thought of, like forcing oil into certain areas under pressure and resealing and such.
Moral of the story is $80 seemed cheap until it didn't last then $247 seemed cheap cos its damn hard to push start a boat when you are 3 miles out!
Not putting a damper on you Kits, have a damn good fiddle with that thing, just realise that sometimes simple ain't that simple.
Wish you luck...............Hush.

[jonbuoy]

That commutator looks good - no groove in it and brushes look like they got plenty of meat on them, pull the brushes back slightly they should spring back onto the commutator.  I would suspect voltage drop not starter.  :

[Frankenkit]

brushes are good looking, springs were good looking... going to see about what TT said.  Battery is holding at 12.6 regularly, charges well, etc etc... *shrug*

[hcritz]

Hello Kit...
A couple of things to check...
Many of the ground brushes make their connection through the small screws that hold the plate to the end cover...then that must ground through it's connection to the starter.
Make sure those areas are clean and free of corrosion.
My GS1150 was giving trouble starting when hot...found the problem there was actually the ground to the engine. That white aluminum corrosion had built up between the starter body and the engine itself...and also the mounting bolts...a bit of sandpaper and some dielectric grease and she starts just fine.
While you are at it...clean and check your batter ground to the engine...corrosion there could be causing a bid drop in voltage to the starter.
Good general maint. to clean and lube the starter anyway though.
ED

[Frankenkit]

Hey,
So this morning I took the whole armature shaft and checked out the field coils inside the shell.  I don't know *exactly* what I'm looking for here, so I looked for spots of wear that would indicate a constant rub.  I saw some spots that looked like they'd received some light friction but that looks almost more vertically oriented, if that makes any sense?  Def. not what I'd visualize for having the shaft touching the field coils any extensive amount.  The armature shaft was pretty uniform, with that orangey-red lube/grease that I think is some kind of lube they used on the alternator rotor, too.  There was one small gouge in the side and I'm really not sure where that could've come from, except from maybe a chunk of carbon or something (?)

Cleaned it up with a dry toothbrush, just sweeping out the carbon and blowing with compressed air after I had stuff loosened up. 

Checked continuity between commutator segments, and the armature shaft, that checked ok, then the commutator segments themselves, that was ok, (i.e. no continuity)  Checked continuity between the brush   and the terminal bolt itself... that was good, too (continuity)

cleaned and lightly oiled the bushings (there was some rust and discoloration on those...)  oiling was done sparingly (as when I took it apart, it was very 'sparing'), just put a couple drops on them, spread the drops out with a q-tip to use the oil to clean, then wiped with a cloth and re-oiled, then used a clean part of the cloth to spread and absorb some of the oil, leaving a sheen, but no drips etc. 

I'm going to look at the brushes etc when they come in- I might end up letting Honda keep the springs and brushes (or just keep them and put them in my 'you'll need these later' parts bin)  but I will install new o-rings, as there was a lot of aluminum oxide around either end of the starter and that o-ring rubber has def. seen better days.

Having mostly concluded the starter itself seems quite functional, I turn my attention to the ground and mounting bolts, and also potentially the battery cable.

[Hush]

Ah that my son should meet such a keen wrencher as you he he.

[Frankenkit]

So... for those who might read this but not the rebuild thread that this sorta connects to, I took the aforementioned starter and put it in my bike because I was having the very same problem I wrote about.  I figured I could get around actually doing anything about it until later, but lo and behold, I got the bike warmed up for a trip to breakfast and... she died, and wouldn't start again.  Let her sit and think about how unfair she was being for a half hour, and she started up just fine, thank god, so I didn't have to push her up the hill again. 

Stuck in the starter and had interesting results.  The cleaned starter seems to spin way more easily than the other.  I hit the starter button and it cranks fast- like you would expect out of a car- engine fires up, then you hear a little 'whirr' as power is cut to the starter and it winds down.  funny. I don't remember hearing that before, but I don't know that I can complain, it starts a lot better now. (like, it starts even when warm.)

Still, when warm, it cranks a bit slower, like it's not getting the voltage it should.  would that be the solenoid or...?  I was riding her around 3-5k rpms in 3rd and 4th  to make sure everything was charging, and that did seem to make a slight difference in the starting, for the better.

The starter motor I removed had some pretty significant slop in the armature shaft- could pull/push in/out about 7mm all told.  Feels weird. I'll tear it apart and look at its guts as soon as I have time.  there was a major difference in the way that one felt vs. the one I just cleaned up, though...

[Hush]

Does this mean you have solved your problem Kits?

[speedy gonzalais]

I had the same trouble with my 650, swapped starters with the other 650 same prob new battery same prob, went thru a lot of testing with the help of some nice ppl on here and the problem turned out to be the earth wire the one that connects to the lhs coil, also my spark units over heated because of this.

[martino1972]

lhs coil

what is that??


oh,and kit's,it probably starts a little slower now when warm cause your compression is higher then.....

[Frankenkit]

I had the same trouble with my 650, swapped starters with the other 650 same prob new battery same prob, went thru a lot of testing with the help of some nice ppl on here and the problem turned out to be the earth wire the one that connects to the lhs coil, also my spark units over heated because of this.

THIS is a point of interest...

my original spark units melted out and were replaced, but I was wondering what would cause that.  What is the LHS coil?  or do you mean the ground wire to the left hand side coil?