Harley Starter Issue. Maybe Solved!

[Tom H]

The problem is that the bike will crank over but not start, sorta like a car with a weak battery, like not enough to run the ignition as well as crank. The battery is charged (12.7V), but runs down very quickly.

The starting problem was an issue for the PO, not sure from new when it started. During the summer, it seems to start well, but in the cold of about 50deg +/- is when the issue really shows itself.

The bike is a 2007 HD Street Bob, FI, 96" with about 15K miles. Battery is an Odyssey PC545 about 2 years old.

I have tried to find the problem with a brand new DMM with clamp on Amp meter. I have cleaned the ground and positive connection, added a temporary  ground wire to the engine. The cables seem to be fine. The only issue that I did notice, even when the temp ground cable was installed was that the ground cable felt warm, not hot, just warm and the positive didn't seem as warm.

The battery to starter is the same as an Eldo/Ambo, pretty simple. Positive to the solenoid and negative to the engine. The bike power is from a wire connected to the positive solenoid terminal.


What I have found so far is that the starter is needing excessively high amps to turn the engine over. Book states that it should use 200 amps max under load. My clamp on meter is bouncing wildly from a low of about 250 to a high of about 450 amps.

I though that maybe the meter is bad. Hooked it up to my Ambo and it had a spike of about 120ish and then settled to about 85-90 amps. The 85-90 was smooth, not like the wildly fluctuating HD starter.

So...before I buy a new starter or try to clean the original, were would you be looking?

I have taken apart and cleaned up Guzzi Bosch starters. But I don't remember having a problem like the HD is having. So if you can point me in the right direction inside that starter, that would be a big help.

I have tried searching the HD forums, but can't find anything like this.

Thanks for your help!
Tom

[KiwiKev]

 Try a known good  battery on it first, even a car battery connected up with jumper leads ? Battery leads getting hot could indicate a thicker wire is needed to carry the high current.

[Kev m]

The other Kev beat me to it.

I was gonna say jump it and see.

But also, disconnect the cables and ohm them as you wiggle em. High resistance = broken cables inside insulation.

Also, you could remove starter and check amperage necessary to crank direct.

[Kiwi_Roy]

You seem to suspect the starter is drawing all the power and not leaving enough for the electronic ignition.
On the schematics I can find the battery seems to be wired directly to the starter solenoid with another wire fed from the solenoid to a 40 Amp fuse that then feeds the ignition switch.
Measure the Voltage at the fuse to chassis, it should be over 12, now while watching the Voltage engage the starter, I would expect it not to drop below 10 or it will be too low for the electronic ignition.

Place your meter across the battery terminals then again measure the Voltage while cranking, what does that read? (tests the batteries ability to supply the load)

Another reading from the battery negative terminal to chassis, it will read zero but what does it read while cranking? (should be less than 1/2 Volt - tests the battery ground)

One other test you can do is pull the main fuse and feed it with 12 Volts from another battery so that you guarantee the electronics is getting full Voltage while the bike battery is supplying the cranking power If it's a case of robbing the electronics the bike should burst into life.

BTW. most clip-on meters are for measuring AC current, are you sure yours is designed for DC?

[twowheeladdict]

Book states that it should use 200 amps max under load. My clamp on meter is bouncing wildly from a low of about 250 to a high of about 450 amps.

What? 

[Tom H]

Yes the meter reads DC as well as AC for the amps.

I'll play some more latter today or tomorrow and see what I find.

I still don't get what would cause such a high amp draw on the positive cable about 2" from the starter, especially compared to the Ambo? Yes I do realize the HD engine is over twice as large, it's about the CC's of my old Datsun.

Thanks so far!
Tom

[fotoguzzi]

I wonder if the PC545 is just too small for a Harley? IIR my Buell had a pc 925.

[Wayne Orwig]

Yes the meter reads DC as well as AC for the amps.

I'll play some more latter today or tomorrow and see what I find.

I still don't get what would cause such a high amp draw on the positive cable about 2" from the starter, especially compared to the Ambo? Yes I do realize the HD engine is over twice as large, it's about the CC's of my old Datsun.

Most DC clamp meters simply measure the magnetic field that they sense on the wire. They can be confused by anything nearby that is magnetic. Solenoids, starters, metal frames, etc. I wouldn't trust it. It probably needs to be very far from metal and anything magnetic.

I would only trust a measured voltage drop across a shunt. Like measuring the voltage drop on the negative lead with the headlight on, a known current. Then measuring the drop while starting. Then do some math.

[bodine99]

The problem is that the bike will crank over but not start, sorta like a car with a weak battery, like not enough to run the ignition as well as crank. The battery is charged (12.7V), but runs down very quickly.

The starting problem was an issue for the PO, not sure from new when it started. During the summer, it seems to start well, but in the cold of about 50deg +/- is when the issue really shows itself.

The bike is a 2007 HD Street Bob, FI, 96" with about 15K miles. Battery is an Odyssey PC545 about 2 years old.

I have tried to find the problem with a brand new DMM with clamp on Amp meter. I have cleaned the ground and positive connection, added a temporary  ground wire to the engine. The cables seem to be fine. The only issue that I did notice, even when the temp ground cable was installed was that the ground cable felt warm, not hot, just warm and the positive didn't seem as warm.

The battery to starter is the same as an Eldo/Ambo, pretty simple. Positive to the solenoid and negative to the engine. The bike power is from a wire connected to the positive solenoid terminal.


What I have found so far is that the starter is needing excessively high amps to turn the engine over. Book states that it should use 200 amps max under load. My clamp on meter is bouncing wildly from a low of about 250 to a high of about 450 amps.

I though that maybe the meter is bad. Hooked it up to my Ambo and it had a spike of about 120ish and then settled to about 85-90 amps. The 85-90 was smooth, not like the wildly fluctuating HD starter.

So...before I buy a new starter or try to clean the original, were would you be looking?

I have taken apart and cleaned up Guzzi Bosch starters. But I don't remember having a problem like the HD is having. So if you can point me in the right direction inside that starter, that would be a big help.

I have tried searching the HD forums, but can't find anything like this.

Thanks for your help!
Tom
DEKA Battery ETX20L they make HD OEM also, starter is fine buy a DEKA or HD batt for your ST
[

[Kiwi_Roy]

Really I think it all comes down to Voltage, lack of it.

Because there is too much resistance in series with the starter terminal (main fuse supply) either in the cables OR inside the battery.

An easy way to monitor that is to measure from the main fuse to chassis either with a Voltmeter or a small 12 Volt lamp.

[Murray]

Don't know the HD series however is this the model that has the battery surrounded by the oil tank, on an oil cooled motor? If so these had a reputation for kicking the living snot out of batteries though some very poor packaging/ you didn't really think that through engineering. Actually rude a crude load lest withthe motor off and a mutlimeter on the battery turn the headlight on if it drops more than about 0.2 of a volt it's toast or at the very least in need of proper load test.

[Tom H]

To start with, thanks for the replies!

So today.....I pulled the bike in the garage so I could get serious with it. Today the air temp was about 75 deg F.

I measured the battery voltage, 12.7V. I am testing with the same battery. I think the battery is good.

I pulled the battery and battery tray to get access to the starter. I also pulled the plug wires and fuel pump fuse so that the bike would not start, but it would crank for as long as I wanted. Again the issue may be cranking with too low a voltage to start the engine.

As a reminder, yesterday I added a brand new car negative cable to bypass the stock neg bat cable with the same amp results. Today I used the same car bat cable to bypass the pos cable.

At first I was happy!!!!! Draw was about 150 amps with everything at ambient temp but still varying alot from 200-120ish while cranking for about 5 seconds twice (don't know the exact length of time, I should have grabbed my 3 monkeys so they could hold a stopwatch and push buttons  . The bike and starter were at whatever temp they were with 75 ish air temp. I thought the cable fixed the problem.

I'm now thinking the pos cable was the problem. A few minutes latter I test again without changing a thing. Now I'm getting wildly varying readings of 200-400 amps. The meter changes so fast I can't get an exact reading.

Remember yesterday the neg cable felt warm, not HOT. I decided to feel the starter today after it was drawing the high amps.. It was quite warm,  you could touch it but it was hot.

Now my battery is getting low. I charge it back up to full in about 20 minutes. I feel the starter and it's still warm, but cooler the before. I crank it again and get the high amp readings again.

Tomorrow I plan to test it again with the pos bypass installed and a full battery at whatever the air temp is. If it gets the 150ish amp reading again when at air temp, then gets the high reading when the starter is warm, I would think the starter has an issue, not the bat or wiring.

Again, thanks for the help so far!!!!
Tom

[Murray]

As the battery runs flat it will provide more current: power (watts) = current (amps) x voltage so I would expect the amperage to go up as the voltage drops, as copper heats up it will provide more resistance and subsquenntly get warm. Full charging the battery in 20minutes sounds a bit off to me at what current? I would expect it take longer IMO off a standard wall charger (4amps) if you've been cranking it quiet a bit. Have you checked you are getting spark while cranking? if you have a timing light stick in on one of the plug wires and see if it triggers while you crank.

[Muzz]

At 12.7 volts fully charged my gut feeling is the battery is sick.  There could well be other stuff but a good battery fully charged should nudge 13 and not drop quickly.

As others have pointed out, as the voltage drops the current increases, and any heating occurring increases by the current squared. 

[Chuck in Indiana]

Full charging the battery in 20minutes sounds a bit off to me

Me, too. An AGM needs to be "conditioned" for a long time. My dedicated Odyssey charger takes overnight to charge a battery. The Odyssey website tells all about it.

[Tom H]

Thanks for the new info.

I think I need to bring this up again. This bike has always had a starting/cranking issue that has been since new from what I understand. It has had at least 3 Harley batteries from the Harley dealer and all had the same issue. Also it has not been used much, about 16K miles.

I installed the Odyssey PC545 and get the same issue. BTW this is the same model battery that is in my EVT. This is also the battery that is recommended by Odyssey: http://odysseybatteries.com/pc545.htm

One more thing I need to bring up is that this issue shows up the most in the winter months when the mornings are in the 40-50F range. During the summer when it's 60-65F, it cranks and starts like I think it should.

I did look at their faq section: http://www.odysseybattery.com/Support/TechnicalInfo and found this:
Full charged ODYSSEY battery voltage is 12.85 volts. ODYSSEY Batteries with less than 12.40 volts cannot reliably
 start big inch engines.

I believe this is referring to larger than stock engines?

This is my battery charger:
https://www.harborfreight.com/automotive-motorcycle/battery/2815-amp-automatic-microprocessor-controlled-battery-charger-63299.html

When the charger shuts off when it's done the battery is at 13 something with the battery in the bike. When charged and it sits overnight the battery is at 12.7 something, close to 12.8.

Today I plan to pull my EV battery that is at least 4 years old and see what it does. It has no problem cranking and starting the EVT. If it has the same issue I will try my PC925 that I have in the Ambo.

Trying to explain the cranking issue is difficult. Right now I'm trying to focus on the very short cranking time I have, not on whether it will actually fire up. Let's say I left off the plug wires and went to start the bike. If I was to crank it for let's say Approximately 3-5 seconds, look for a problem, then 3-5 seconds more and then find the problem, I may not have enough power left to actually crank and fire up the bike.

Also I wanted to mention again that while I'm testing this I do not have the spark plug wires connected to the installed spark plugs. I do have spare set of spark plugs in the wire and grounded to the engine.

This bike WILL start in one or two revolutions when all is well. Again I do not want it to start until I figure out if it's the battery or the starter.

Maybe I'm looking at the problem backwards or sideways. My dad was an electrical engineer, unfortunately it did not rub off on me.

I'll let you know what I find today.

Thanks again,
Tom

[jbell]

At 12.7 volts fully charged my gut feeling is the battery is sick.  There could well be other stuff but a good battery fully charged should nudge 13 and not drop quickly.

As others have pointed out, as the voltage drops the current increases, and any heating occurring increases by the current squared.

   12.7V  fully charged is not healthy.  It might be okay, but not top condition.  Could be the battery or the charging system.  When charging, your bike should be putting out about 14V or a bit more.

[stubbie]

Agree 12.7V not good.

[Tom H]

In a nutshell.

Tried the HD PC545, EV PC545 and the battery out of my '62 F100 262 I6. All had the same issue of short crank time and high crank amps.

The HD was at 12.77V, the EV 12.33, the truck 12.2 The EV and truck start just fine at these numbers.

The truck bat gave me the smoothest reading, it does hit 450 amps.

BTW: My EV takes 55-60 amps to crank and start.

With the truck bat, I even moved the ground wire directly to a lug on the starter. While using the truck bat, I would take breaks and charge it up.

Speaking of charging. The HF charges AGM at 14.7V which is inline with Odyssey spec. I have an acient Craftsman charger that charges at 13.7V.

The HD Odyssey went flat so I put it on the HF charger. At 1:30pm the charger did it's auto shut off when done. I tested the volts within a minute or two.

13.04v 1:30
12.97v 1:33
12.88v 2:30
12.88v 2:40
12.86v 3:30
12.84v 5:00

I tried the HD PC545 again after it's charge as above and still have the high draw and short crank time. This is with the ground attached to a lug on the starter.

I plan to pull the starter and see if I can find anything wrong with it. Thenn if the starter has an issue I will get a new one if this one can't be repaired at a decent price.

Thanks again!!!!!!
Tom

[jdgretz]

Interesting that the Odyssey website does not show a battery for the Harley Street Bob.

The CCA for the PC545 is listed as 150.

Motobatt shows a MBTX30U as being the correct battery with 385 CCA.

YUASA shows their YIX30L-BS with 400 CCA.

Even Harley recommends a battery with at least 315 CCA (their own brand)

I'd be worried that the battery is undersized for the bike.  While I know it seems to work in some folks bikes, I'd be suspicious of the low CCA if it is reporting slow or hard starting.

jdg

[Muzz]

Does anyone else think 450 amps is a tad high?

A 2lit car draws 160-300 amps more or less.  The Harley has big pots of course; may just be a very large starter fitted to it.

[Murray]

Does anyone else think 450 amps is a tad high?

A 2lit car draws 160-300 amps more or less.  The Harley has big pots of course; may just be a very large starter fitted to it.

A smidge but its trying to compress a larger swept in one hit rather than have it broken up into four smaller parts. Surely out there in the world of HD there is a resitance reading for the windings of the starter, as it is drawing plenty of current it doesn't suggest there is a dirty or poor connection that would reduce the current flow.

12.7 volts for a battery not under charge would be what I expect, if your charging system was showing that at rpm then yes there is an issue.

[twodogs]

Sounds like a issue I had years ago and it turned out to be the starter drive gear, replaced it and all was good again.

[s1120]

Thanks for the new info.

I think I need to bring this up again. This bike has always had a starting/cranking issue that has been since new from what I understand. It has had at least 3 Harley batteries from the Harley dealer and all had the same issue. Also it has not been used much, about 16K miles.

I missed that it always had this issue. Could it be a mechanical issue?  Just a thought... its always hard when you have a issue its always had.. it kicks out a lot of things that wear/go bad, and opens up the door to ANYTHING. And you could be on the right track that its just a bad starter, and its always been baid since day one...  it does happan.

[Tom H]

Twodogs...Do you mean the entire starter or just a part inside it?

Murray...the bikes charging system charges at 14.something. Idle is mid to upper 13 I think.

A friend brought up an interesting thought when I said that the engine is so big that it takes more to crank it over. His reply was that within reason, if the compression ratio was the same  and the number of cylinders the same, it should take about the same to crank it. Don't know if that's true or not.

Today I'll pull the starter and see what it takes to turn it on the bench. The book has a spec for this as well as rpm. Don't have a way to measure rpm.

Thanks again so far!!!
Tom

[twodogs]

It was inside the starter, I pulled the starter and replaced the starter drive gear, it has been a few years but that's what I recall. I had a big motor and I went to the biggest battery I could get and still nothing so before I bought a high end starter a friend told me to try the gear and it worked, I had the bike for 8 more years after that and never had another issue with it. Not sure if that is your issue but something to look at 

[twowheeladdict]

Twodogs...Do you mean the entire starter or just a part inside it?

Murray...the bikes charging system charges at 14.something. Idle is mid to upper 13 I think.

A friend brought up an interesting thought when I said that the engine is so big that it takes more to crank it over. His reply was that within reason, if the compression ratio was the same  and the number of cylinders the same, it should take about the same to crank it. Don't know if that's true or not.

Today I'll pull the starter and see what it takes to turn it on the bench. The book has a spec for this as well as rpm. Don't have a way to measure rpm.

Thanks again so far!!!
Tom

Does the Harley have some type of compression release to help with starting so that the starter isn't trying to pump those big jugs?  I know my Vulcan Voyager 1700cc would hold the exhaust valves open slightly when starting.

[Tom H]

TWA... as far as I know, no.

Took the starter apart today. Looks great inside. Never seen aluminum look so shiny! All bench tests that I could do while it was apart were fine.

I plan to take the armature to a electrical shop and see if they can do the growler test. That's the last thing to check.

Thanks again!!
Tom

[Tom H]

I took the armature to the shop today. Their growler hasen't worked for the last 5 years, they never use it anymore. Go figure. Tried the Harley dealer service dept., they can't do it either, The starter shop looked at it and said that if all the other readings are fine, it looks good to him where he would see an issue the growler would point out. So I installed it.

Bench test showed 90-95 amps with it at 90 mainly. I think it had a very short start up spike of 110 or the like This is free spinning clamped in my vice. This is in spec. with the book.

As a side note I checked how much it takes to activate the solenoid, 4 amps, think it spiked a 5.

Another note. The starter shop confirmed to me that a low battery will show a high amp output compared to a fully charged like new condition battery. This boggles my mind, he kinda agreed with that. Strange but true

Now I'll stuff it back in the bike and try the HD's PC545 again as a test, then I'll grab a PC925 out of my Ambo and see what happens.

Again, thanks all so far!
Tom

[fotoguzzi]

Now I'll stuff it back in the bike and try the HD's PC545 again as a test, then I'll grab a PC925 out of my Ambo and see what happens.

Again, thanks all so far!
Tom