Author Topic: What's the most common cause of a weak starter?  (Read 10580 times)

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Offline 754

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Re: What's the most common cause of a weak starter?
« Reply #75 on: December 27, 2020, 03:42:03 PM »
Sooner or later, you will realise your other battery was in bad shape..
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Offline juntjoo

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Re: What's the most common cause of a weak starter?
« Reply #76 on: December 27, 2020, 03:46:24 PM »
Sooner or later, you will realise your other battery was in bad shape..

I DID! Lol. I always thoroughly update my threads with what I discover. And actually I believe all my issues in the past with starting were mostly due to the battery and how I mis-"maintained" it.

Just to keep my last question visible:

Current battery starting fine at 11.9 volts. Is that unhealthy? Need I "maintain" it above 12v for longer battery life? Thanks guys
-Ben

82 Nighthawk 650..

1982 Honda Nighthawk...

I HAVE A 1982 HONDA NIGHTHAWK FFS! j/k. It's my only bike, my first and last.

Offline 74CB750K4

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Re: What's the most common cause of a weak starter?
« Reply #77 on: December 27, 2020, 03:57:30 PM »
That device is not the same.

It is essentially a large hammer when a small hammer is needed.

To be fair, set correctly this one does trickle charge and claims to auto shut off.  However, I don't trust too many items like this from Harbor Freight. I have a Battery Tender Plus, and just bought a double one to charge my bike and a car that sits in the garage. Plug them in and forget it, easy peasy.
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Offline robvangulik

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Re: What's the most common cause of a weak starter?
« Reply #78 on: December 27, 2020, 04:05:17 PM »
If the bike starts good now, I think your meter has gone haywire. If another meter says the same, your bike won't start well for long.

Offline Scott S

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Re: What's the most common cause of a weak starter?
« Reply #79 on: December 27, 2020, 04:40:08 PM »
 If your brand new battery is already at 11.9V, I'd be suspicious of a charging problem.

 Start the bike and put your multimeter on the battery posts. Have someone rev the engine past ~2500-2600 and see what the meter reads. Report back.
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Offline Alan F.

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Re: What's the most common cause of a weak starter?
« Reply #80 on: December 27, 2020, 04:51:47 PM »
That device is not the same.

It is essentially a large hammer when a small hammer is needed.

To be fair, set correctly this one does trickle charge and claims to auto shut off.  However, I don't trust too many items like this from Harbor Freight. I have a Battery Tender Plus, and just bought a double one to charge my bike and a car that sits in the garage. Plug them in and forget it, easy peasy.

2 amps is quite high for trickle charging, in my opinion, opinions do vary though.

Offline 74CB750K4

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Re: What's the most common cause of a weak starter?
« Reply #81 on: December 27, 2020, 05:26:26 PM »
That device is not the same.

It is essentially a large hammer when a small hammer is needed.

To be fair, set correctly this one does trickle charge and claims to auto shut off.  However, I don't trust too many items like this from Harbor Freight. I have a Battery Tender Plus, and just bought a double one to charge my bike and a car that sits in the garage. Plug them in and forget it, easy peasy.

2 amps is quite high for trickle charging, in my opinion, opinions do vary though.

Oh I would definitely NOT use that one for maintaining, just saying it has that setting. I like name brand tried and trusted equipment.
1974 CB750 K4 Flake Sunrise Orange

Offline juntjoo

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Re: What's the most common cause of a weak starter?
« Reply #82 on: December 27, 2020, 06:01:43 PM »
If your brand new battery is already at 11.9V, I'd be suspicious of a charging problem.

 Start the bike and put your multimeter on the battery posts. Have someone rev the engine past ~2500-2600 and see what the meter reads. Report back.

2 volts. I think that means good. 2+10 volts is 12. Yeah?
-Ben

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I HAVE A 1982 HONDA NIGHTHAWK FFS! j/k. It's my only bike, my first and last.

Offline Kevnz

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Re: What's the most common cause of a weak starter?
« Reply #83 on: December 27, 2020, 08:50:20 PM »
I used to be a telephone technician back in the day. All the exchanges had lead\acid batteries as backup in case of power failure. Part of my duties was to " cycle" the batteries, which meant taking a specific gravity check of all the cells using a hydrometer and then discharging the batteries until they dropped to a specific voltage. Batteries were then put on charge until they reached a specific voltage and the s\g stayed constant over 3 consecutive readings an hour apart. That indicated the battery was fully charged. The point of discharging was to remove the buildup of crud on the plates, prolonging the life of the battery. These things were a metre high, by 1\2 metre square , were open to the atmosphere and weighed heaps, so you didn't want to be replacing them too often. The good battery " conditioners" do the same task, "cycling the battery to minimize sulphation of the plates. As mentioned by others, will pay for itself in battery life in no time, especially as bike batteries tend to lead a hard life, often not being used for months at a time. Our bikes, in standard form at least, don't have a residual drain on a battery when idle, but modern ones with anti theft, clocks, computers etc do, and will often discharge a battery within a few weeks of idleness. Back in the day this was not an issue as usually our bike was our sole (and soul) means of transport and they didn't sit round long enough to go flat!
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: What's the most common cause of a weak starter?
« Reply #84 on: December 27, 2020, 10:58:09 PM »
So I've been starting up almost flawlessly. Don't have a maintainer yet, which I may get later for other batteries but for now waiting on an extension ion cable for my solar trickle charger which I plan on using here and there to maintain my bike's battery but my digital voltage meter on my bike is giving me 11.9v before starting bike, which it does with little struggle. Not as good as if it were 12.4v. So I need to keep it at above 12 for best "health", longest battery life?

So you finally listened and got your new battery. Good.

Did you hit it with a full charge prior to using it?

Are you riding it or just playing in your garage?

If you are taking it on the highway for some miles and it has run down to 11.9V you do have a charging issue.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: What's the most common cause of a weak starter?
« Reply #85 on: December 27, 2020, 11:02:54 PM »
If your brand new battery is already at 11.9V, I'd be suspicious of a charging problem.

 Start the bike and put your multimeter on the battery posts. Have someone rev the engine past ~2500-2600 and see what the meter reads. Report back.

2 volts. I think that means good. 2+10 volts is 12. Yeah?

No No No !!!!! Take multiple readings at multiple rpm levels. This is a diagnosis of the output of your charging system. This isn't necessarily about your battery but DO start with a fully charged battery around 12.6 - 12.8V. Write down each rpm and voltage. IMO read the sitting voltage, idle voltage and every 1000 rpm increase up to 5000 or 6000 rpms.

Give us a full report of all the rpm ranges
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Scott S

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Re: What's the most common cause of a weak starter?
« Reply #86 on: December 28, 2020, 04:00:40 AM »
If your brand new battery is already at 11.9V, I'd be suspicious of a charging problem.

 Start the bike and put your multimeter on the battery posts. Have someone rev the engine past ~2500-2600 and see what the meter reads. Report back.

2 volts. I think that means good. 2+10 volts is 12. Yeah?

 Um...no.
 And where did the 10 volts come from?
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Offline Deltarider

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Re: What's the most common cause of a weak starter?
« Reply #87 on: December 28, 2020, 04:20:56 AM »
Reading Volts at several RPM doesn't tell you much about the health of the battery.
Also I think it's a waste of energy to have a battery on a tender all the time. My charger has this function too. I never use it. It's succesful advertisement bla IMO. So the last month and a half (hibernation) I have done this experiment. I began with a fully charged battery and then had it connected to a 1A charger. Between the charger and the grid power I have a simple timer that I had lying around unused. Every day the battery is charged at 1A for 30 mins to compensate for eventual drain. So far it workes great. The charger has leds that tell in 20% increments what the state of charge is. Some five minutes before the timer shuts off the charger, a 100% is reached.
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Offline juntjoo

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Re: What's the most common cause of a weak starter?
« Reply #88 on: December 28, 2020, 04:36:53 AM »
If your brand new battery is already at 11.9V, I'd be suspicious of a charging problem.

 Start the bike and put your multimeter on the battery posts. Have someone rev the engine past ~2500-2600 and see what the meter reads. Report back.

2 volts. I think that means good. 2+10 volts is 12. Yeah?

 Um...no.
 And where did the 10 volts come from?

I thought I read somewhere if it goes below 10 volts its not good.
-Ben

82 Nighthawk 650..

1982 Honda Nighthawk...

I HAVE A 1982 HONDA NIGHTHAWK FFS! j/k. It's my only bike, my first and last.

Offline juntjoo

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Re: What's the most common cause of a weak starter?
« Reply #89 on: December 28, 2020, 04:38:06 AM »
If your brand new battery is already at 11.9V, I'd be suspicious of a charging problem.

 Start the bike and put your multimeter on the battery posts. Have someone rev the engine past ~2500-2600 and see what the meter reads. Report back.

2 volts. I think that means good. 2+10 volts is 12. Yeah?

No No No !!!!! Take multiple readings at multiple rpm levels. This is a diagnosis of the output of your charging system. This isn't necessarily about your battery but DO start with a fully charged battery around 12.6 - 12.8V. Write down each rpm and voltage. IMO read the sitting voltage, idle voltage and every 1000 rpm increase up to 5000 or 6000 rpms.

Give us a full report of all the rpm ranges

K, I'll do this next...
-Ben

82 Nighthawk 650..

1982 Honda Nighthawk...

I HAVE A 1982 HONDA NIGHTHAWK FFS! j/k. It's my only bike, my first and last.

Offline Scott S

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Re: What's the most common cause of a weak starter?
« Reply #90 on: December 28, 2020, 04:51:56 AM »
If your brand new battery is already at 11.9V, I'd be suspicious of a charging problem.

 Start the bike and put your multimeter on the battery posts. Have someone rev the engine past ~2500-2600 and see what the meter reads. Report back.

2 volts. I think that means good. 2+10 volts is 12. Yeah?

 Um...no.
 And where did the 10 volts come from?

I thought I read somewhere if it goes below 10 volts its not good.

 2 is below 10.

 With the engine revved, you should be seeing around 14 14.6 V.
'71 CB500 K0
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Offline juntjoo

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Re: What's the most common cause of a weak starter?
« Reply #91 on: December 28, 2020, 04:54:48 AM »
If your brand new battery is already at 11.9V, I'd be suspicious of a charging problem.

 Start the bike and put your multimeter on the battery posts. Have someone rev the engine past ~2500-2600 and see what the meter reads. Report back.

2 volts. I think that means good. 2+10 volts is 12. Yeah?

 Um...no.
 And where did the 10 volts come from?

I thought I read somewhere if it goes below 10 volts its not good.

 2 is below 10.

 With the engine revved, you should be seeing around 14 14.6 V.

K, well that was not fully charged and cold. I'll be doing a more thorough test in a bit and report back.

Oh, wherever I read "below 10"i was thinking below 10 LESS THAN what it started at
« Last Edit: December 28, 2020, 04:56:33 AM by juntjoo »
-Ben

82 Nighthawk 650..

1982 Honda Nighthawk...

I HAVE A 1982 HONDA NIGHTHAWK FFS! j/k. It's my only bike, my first and last.

Offline StockRider

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Re: What's the most common cause of a weak starter?
« Reply #92 on: December 28, 2020, 05:06:06 AM »
You have other threads about grip warmers and splicing wires for rear lighting repairs..., make sure your testing is done with accessories removed/wiring as OEM as possible to establish a baseline for your electrical system.
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Offline juntjoo

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Re: What's the most common cause of a weak starter?
« Reply #93 on: December 28, 2020, 05:26:43 AM »
You have other threads about grip warmers and splicing wires for rear lighting repairs..., make sure your testing is done with accessories removed/wiring as OEM as possible to establish a baseline for your electrical system.

Well I'll need my volt meter to test. Other than that I just battery charging kit that just puts a fuse in there and the grip warmers which are usually in the off position. You saying I could have a parasitic drain or something with these? I'll keep that in mind.
-Ben

82 Nighthawk 650..

1982 Honda Nighthawk...

I HAVE A 1982 HONDA NIGHTHAWK FFS! j/k. It's my only bike, my first and last.

Offline Deltarider

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Re: What's the most common cause of a weak starter?
« Reply #94 on: December 28, 2020, 05:33:35 AM »
I thought I read somewhere if it goes below 10 volts its not good.
When voltage drops below 10 Volts during cranking electrically battery is no longer good.
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Offline StockRider

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Re: What's the most common cause of a weak starter?
« Reply #95 on: December 28, 2020, 06:36:02 AM »
You have other threads about grip warmers and splicing wires for rear lighting repairs..., make sure your testing is done with accessories removed/wiring as OEM as possible to establish a baseline for your electrical system.

Well I'll need my volt meter to test. Other than that I just battery charging kit that just puts a fuse in there and the grip warmers which are usually in the off position. You saying I could have a parasitic drain or something with these? I'll keep that in mind.

I re-watched your video from the first page of this thread http://forums.sohc4.net/index.php/topic,185320.msg2146075.html#msg2146075. If the volt meter you are referring to is the SAE attached accessory (possibly with USB ports) then I would recommend disconnecting that, the grip warmers, and any other additional wiring add-ons. Use your Innova multimeter to read voltages.
« Last Edit: December 28, 2020, 07:12:19 AM by StockRider »
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Offline juntjoo

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Re: What's the most common cause of a weak starter?
« Reply #96 on: December 28, 2020, 08:57:42 AM »
So here is my latest test and summary of my electrical situation. What do you think? Why do my two circuits give low voltage? And how's my solar charger apparently pulling 20 volts?

-Ben

82 Nighthawk 650..

1982 Honda Nighthawk...

I HAVE A 1982 HONDA NIGHTHAWK FFS! j/k. It's my only bike, my first and last.

Offline StockRider

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Re: What's the most common cause of a weak starter?
« Reply #97 on: December 28, 2020, 10:05:37 AM »
I'm not an expert in this field but a few recommendations:
1.) Wiring harness will always introduce some voltage drop, 0.2V-0.5V(+).
2.) Test with all after-market parts removed. I see that you disconnected your extras at the SAE plugs but the wiring (with uninsulated connectors :o) is running all around the bike (screenshot below).
3.) Be aware of power demand and power production for any accessories. I don't know the make/model of your solar charger but the open circuit voltage does not seem abnormal (see image below).
4.) Have you double checked the polarity of your pigtails? That could be part of the issue with your SAE plug volt meter not reading at the other location.
5.) "Is that dangerous. I always forget which one to do first..." If you check the manual for your charger it will likely tell you to unplug it from the AC supply before disconnecting..., opposite order for connecting.
« Last Edit: December 28, 2020, 10:11:24 AM by StockRider »
'70 CB750K0 - "Truck" | 4x4 | 4 Cables/4 Carbs/4 Cyls/4 Pipes | PO: "Old J.O.", a.k.a. Dad, Ride Free Brother!

Offline juntjoo

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Re: What's the most common cause of a weak starter?
« Reply #98 on: December 28, 2020, 04:11:38 PM »
Stuck at Northern tool miles from home. Fortunately I was close enough to Walmart to pick up this tender/jump starter coming with 80% charge, but my battery is so dead by the time I got my seat back on the battery died again! So now I'm directly charging both at the wall here. Next step is taking all devices off the  start over. But I don't recall anything being much better before I got all the bells and whistles. We'll see. I guess my rotor wasn't the main issue. But it was on its way out anyway if I recall the ohms weren't in spec.
-Ben

82 Nighthawk 650..

1982 Honda Nighthawk...

I HAVE A 1982 HONDA NIGHTHAWK FFS! j/k. It's my only bike, my first and last.

Offline Scott S

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Re: What's the most common cause of a weak starter?
« Reply #99 on: December 28, 2020, 04:17:26 PM »
 You're in SW Florida; lose the grip heaters.
 Return everything to the stock state.

 Read up on how to test the 650 charging system. Follow THOSE DIRECTIONS; don't make up your own method.
 You have either 1) a charging problem,  or 2) a parasitic drain.

 Your new battery may be salvageable, but test the stock wiring and charging system first.
'71 CB500 K0
'17 Triumph Street Scrambler
'81 Yamaha XS650