Grinding sound when cranking hot, bad battery?

[Plavna]

6 hours ago, JZH said:

US import?  Strange for someone to remove the remote reserve switch.  Do you have a low fuel light in the tachometer?

 

 

Ciao,

 

JZH

Its not the import. R/R failure is common so previous owner instaled voltmeter.

[Plavna]

Is there any other starter motors from other Honda models that I can use, if I need to buy 2nd hand one for replacement? 

[Captain 80s]

That starter motor design is very robust.  Settle down and cross that bridge if needed.

 

The only starter motors I've had to replace are the crappy 2 brush versions that the VF1000F/R came with.  And I replaced with used VFR (4 brush) starters.

[Plavna]

1 hour ago, Captain 80s said:

That starter motor design is very robust.  Settle down and cross that bridge if needed.

 

The only starter motors I've had to replace are the crappy 2 brush versions that the VF1000F/R came with.  And I replaced with used VFR (4 brush) starters.

Good to know that, thanks.

 

Also, one thing that I hope isn't related to this problem. The famous pink connector which is near starter solenoid is slightly melted on one side, but not that much. Dunno if that can be the cause of this problem, cuz its not giving the power to the starter.

 

I guess somehow starter motor gets heat soaked, but I never heard that is problem on any motorcycle...

[Captain 80s]

It's the abundant amount of brush dust that increases the resistance of the starter motor and gets worse with heat.

 

You can buy replacement wire lead / plugs for the relay and you simply must replace it at this point.  Solder or solder-seal a new one in.  I've been doing this a lot lately and is a common issue on these bikes.

[Plavna]

20 minutes ago, Captain 80s said:

It's the abundant amount of brush dust that increases the resistance of the starter motor and gets worse with heat.

 

You can buy replacement wire lead / plugs for the relay and you simply must replace it at this point.  Solder or solder-seal a new one in.  I've been doing this a lot lately and is a common issue on these bikes.

 

I will probably sort that plug the last. Problem is that I don't have electric or soldering knowledge and also I don't have these small OEM parts in my country so I need to order it from abroad on which I need to pay shipping + tax +customs... 

 

Should I sandpaper the commutator or is it enough to clean it with contact cleaner, rug and tootbrush? Someone say you can sandpaper it, someone you shouldn't.

[Captain 80s]

Sand the brushes a little.

 

I know this sounds weird, but get yourself an old school red rubber eraser for the armature.  Anybody that raced slot cars knows what I'm talking about.

 

Look into solder seal wire connectors and a good heat gun if you're solder skills are lacking.  You can source the plug kits off ebay.

[Plavna]

I have some 30W soldering iron that I bought for the electronic, don't know if thats enough. 

 

I will post the pictures or write after I open the starter and see what is inside :)

[Plavna]

I got it out :) Tomorrow I will countinue. 

 

I guess these lines are aligment marks. Is this properly aligned?

 

They are not 100% lined but I guess this is fine?

[Plavna]

That exit gear shaft is in the motor oil right? Should I grease it when Im putting it back or not?

[Captain 80s]

That little bit off is fine. 

 

No need to grease the spline, just lube up the o-ring with a touch of oil when reinstalling.

[Plavna]

1 hour ago, Captain 80s said:

That little bit off is fine. 

 

No need to grease the spline, just lube up the o-ring with a touch of oil when reinstalling.

 

Ok here are some insights :)
One washer is chipped, don't know how much is that important but just to notice.

Inside, some black dust, not that much but there is. 

 

--

 

Now these brushes (movable parts) are 10mm in height and 5mm wide. I measured only the part that is sticking out, not the inside. I read in manual that minimum is 6,5mm but don't know what to measure.

 

-

 

Now this is a commutator, I see that the copper part is black, can I sandpaper this with a fine sandpaper? 


 

 

Also you said something about red rubber eraser, so that is for that fatter aluminium part right?

[Captain 80s]

As long as the brushes have to get pushed back a fair amount when re-installing, they are likely fine.

 

The Red Eraser is to clean up where the brushes run.  At least that's what I use, non-destructive and polishes it up.  Finish with some electronics cleaner.

 

Yeah, that doesn't look too bad in there.  Still worth doing.  There will be a fair amount that gets washed out around the magnets in the body too.

 

Wait...  is that just a 2 brush starter?  Or are the other two on the body still.

[Plavna]

Well I can see only two brushes on the holder. 

 

https://www.wemoto.com/bikes/honda/vfr_750_fl__rc36/90/picture/starter_motor_carbon_brush_and_holder

[Plavna]

Too bad there isnt full presoldered repair kit, so I can just put it in and thats it. If I order this part above, don't know if I need to order brushes separately, and the terminal also...

 

I suspect that brushes are worn. I will try to clean but I don't have high hopes.

 

If that doesn't help, the fix will probably wait another season.

 

[Plavna]

Maybe this will work

 

https://www.msjoker.rs/prodavnica/rezervni-delovi/skuteri/starteri/delovi-startera/cetkice-anlasera-sa-nosacem-hondayamahasuzukikawasaki-125-750cc/

 

I hope this holder is universal shape?

[Plavna]

Update: Brushes are pushed by the commutator so I guess its fine. 

 

In the process, I somehow lost one O ring and cant find it...

 

This is just stressfull...

[Plavna]

Everything set, started fine, now I will let it to get some heat and see if that did anything. 

 

Thanks for you help I will reply if the problem is solved or not.

[Plavna]

Tested it without fairings, let it turn the fans, drive it, let it idle...  It looks like it cranks a bit faster, so far not draging when its hot but will check when I get the fairing on. Maybe with fairings there is more heat down below. Its a bit more noisy when starting hot but so far no draging. 

 

 

[Captain 80s]

In any case, it's good preventative maintenence...   if you can keep track of all the parts.

 

Sounds like some initial good news tho.

[Plavna]

Yeah at least I learned something new to do and if I need to do it again, it will be faster and easier to do. 

 

I will ride and see.  If the problem persists, I will go with new brushes, then solenoid. I would change the cables too over time, but can't find new battery/starter cables for this bike.

[Plavna]

Not much time for testing, get some milisecond grind sound, engine cold, not the first start by I was ridding maybe 1km to my parents, then shut off, start again, milisecond grind but starts fine. Few more starts, no problem.
If the hot start problem persists this is the next:
1. New starter solenoid

2. New holder with brushes
3. MAYBE check the starter clutch, if fine check torque on 3 bolts.
4. Check battery and starter cables for corosion. I can clean them but I doubt I can find the new one...
5. Buy new pink plug that is located near starter solenoid. Famous for melting, mine has slight melt but doubt thats was/is the culprit.

 

If it stays like this, Im fine with it.
Will report.

[Plavna]

Update: Temperature dropped to around 20C, I done some short <1km ride to the store, same grind after first try, second try I started it. Like the very short rides don't charge the battery up, but as I know it shouldn't be like that with good battery and mine is.

Then I have ridden to the next store which is like hundred meter apart, turned off, and started without any problems and went home.

 

Not big problems but annoying for me.

[Plavna]

Also are there any other engine grounds to check except that main one on the left side from the negative battery terminal?

[Plavna]

 

 

 

Red arrow, I have this on my 3rd gen, don't know from which part is this wire.
Blue arrow- I don't have there any wire on 3rd gen. Its just a holder for coils or smth.