Starter Issue? Display goes dead.

[Donal]

I have demonstrated this so many times on vehicles... blah, blah, blah...Now crank it and see what happens. The cranking will be slower, the amp draw goes up...I know it doesn't make sense unless you see it for yourself and it defies ohm's law...

Watts up with that? Err, it's about the watts. Even though you are playing games to force voltage and current to change the load resistance remains essentially the same so the delivered watts remain the same until the battery starts to deplete. The voltage/current ratio will proportionally go down and the watts will reduce by the same percentage.

Not sure I completely agree with that. It's really about total impedance, which consists of a (algebraic) combination of resistance, inductive reactance & capacitive rectance. Inductive reactance in this case is provided by back EMF from the starter motor. The faster it spins the higher the EMF which limits the current. The slower it spins the lower the EMF which allows the current to rise.

 

[JR'SFJR]

Had to do it!!! Took about 10 mins. to test my FJR with a clamp on DC ammeter. 105 amps normal cranking amps. cold with a screwdriver jammed between the relay bolts. Disconnected the neg. cable and installed a one foot smaller dia. jumper lead for resistance-voltage drop. Starter draw went up to 125-130 amps and cranked much slower. Please try it.

 

[yamafitter]

^^^^^^^

To quote someone else on this forum.

Thanks

It was one of my Physics professors at University of Waterloo that once said if experimental observations don't match the theory you don't change the observations, you change the theory.

Also in my 35 years of power industry electrical / instrumentation maintenance experience trumps theory every time.

However it is some pretty basic motor theory that exactly explains why the current is rising when the starter doesn't crank at it's proper RPM as Donal stated. Then again the English think electricity flows in the other direction and by code they mount their light switches upside down. I think it has to do with the electrons driving on the wrong side of the road.

Actually it is a matter of comparing inrush current to running current at full voltage compared to reduced voltage that tells the tale. The experiment that JR'SFJR performed for us proves the point.

All that being said in this case it is still probable that the starter is worn out and needs an overhaul. The only reason I mentioned this was, as JR'SFJR stated, the off chance that if there was a relay issue it would be an easy check to make before going through all the hassle of pulling the starter.

 

[rbentnail]

Not sure I completely agree with that. It's really about total impedance, which consists of a (algebraic) combination of resistance, inductive reactance & capacitive rectance. Inductive reactance in this case is provided by back EMF from the starter motor. The faster it spins the higher the EMF which limits the current. The slower it spins the lower the EMF which allows the current to rise.

No way, you didn't just do that! "Impedance" and "reactance" are terms reserved for AC circuits.

 

[frankenfeejeer]

I had this exact same problem with my '04 when I bought it.

Did the battery thing as recommended by the good folks in this forum. Finally replaced the battery and the problem seemed a bit better. But the dragging still persisted.

Tested the battery, stator, connections, etc.

Finally found a used starter on EBay and replaced the starter. Checked the valves and replaced the valve cover gaskets at the same time.

Now it starts perfectly every time. Just like it should. Seems the bearings/bushings were going out in the starter. It really wanted to start the bike, and would use all possible power available to do so (including the power to the gauges), but just couldn't compensate for the additional drag.

Good luck!!

 

[mcatrophy]

...Then again the English think electricity flows in the other direction and by code they mount their light switches upside down. I think it has to do with the electrons driving on the wrong side of the road....

Which is why we run our mains electricity at 240 volts. 110 would never cope with the up-hill switches.

 

[yamafitter]

...Then again the English think electricity flows in the other direction and by code they mount their light switches upside down. I think it has to do with the electrons driving on the wrong side of the road....

Which is why we run our mains electricity at 240 volts. 110 would never cope with the up-hill switches.

But your electricity runs at a very lackadaisical 50 Hz rather than the more hyper 60 Hz we have on this side of the pond. That means your utility company has to push the electrons a lot harder into the end of the wire at their end of the cable to get any work out of the electrons.

I know this stuff because I worked for the provincial power utility for 35 years. My neighbours think I get my electricity for free. I tell them we were allowed to bring electrons home by the bucketful and my basement is completely stocked up with electricity.

 

[Donal]

Not sure I completely agree with that. It's really about total impedance, which consists of a (algebraic) combination of resistance, inductive reactance & capacitive rectance. Inductive reactance in this case is provided by back EMF from the starter motor. The faster it spins the higher the EMF which limits the current. The slower it spins the lower the EMF which allows the current to rise.

No way, you didn't just do that! "Impedance" and "reactance" are terms reserved for AC circuits.

if we were talking about a simple battery/bulb type circuit I would tend to agree with you (although there will be capacitance between cables if they are run close together & by definition capacitive reactance). However when we are talking about windings rotating in a magnetic field then there will definitely be induction with consequent inductive reactance more commonly referred to as back EMF.

 

[Fred W]

OK, I see how this is happening. Yes, the feed to the motor is direct current but after switching that current through the motor's commutator and brushes, for all intents it is pulses of DC that are being applied to the motor's inductive windings. As the motor speed is reduced for any reason the switching effectively slows down, resulting in a lower applied frequency of those pulses into the same inductance coils.

As the frequency decreases so too does the inductive reactance of the coils (the counter EMF if you will). In other words the load resistance of the motor will decrease with a reduction in motor speed resulting in the increased current. Seems simple now that I've thought it through.

 

[yamafitter]

OK, I see how this is happening. Yes, the feed to the motor is direct current but after switching that current through the motor's commutator and brushes, for all intents it is pulses of DC that are being applied to the motor's inductive windings. As the motor speed is reduced for any reason the switching effectively slows down, resulting in a lower applied frequency of those pulses into the same inductance coils. As the frequency decreases so too does the inductive reactance of the coils (the counter EMF if you will). In other words the load resistance of the motor will decrease with a reduction in motor speed resulting in the increased current. Seems simple now that I've thought it through.
I was wrong.

Fixed it for you Fred.

 

[Donal]

OK, I see how this is happening. Yes, the feed to the motor is direct current but after switching that current through the motor's commutator and brushes, for all intents it is pulses of DC that are being applied to the motor's inductive windings. As the motor speed is reduced for any reason the switching effectively slows down, resulting in a lower applied frequency of those pulses into the same inductance coils. As the frequency decreases so too does the inductive reactance of the coils (the counter EMF if you will). In other words the load resistance of the motor will decrease with a reduction in motor speed resulting in the increased current. Seems simple now that I've thought it through.

That's pretty much how I see it. My problem with explaining things is I tend to be very economical with words

 

[mcatrophy]

...Then again the English think electricity flows in the other direction and by code they mount their light switches upside down. I think it has to do with the electrons driving on the wrong side of the road....

Which is why we run our mains electricity at 240 volts. 110 would never cope with the up-hill switches.

But your electricity runs at a very lackadaisical 50 Hz rather than the more hyper 60 Hz we have on this side of the pond. That means your utility company has to push the electrons a lot harder into the end of the wire at their end of the cable to get any work out of the electrons.

I know this stuff because I worked for the provincial power utility for 35 years. My neighbours think I get my electricity for free. I tell them we were allowed to bring electrons home by the bucketful and my basement is completely stocked up with electricity.

You are, of course, absolutely correct. I worked in the aero-space industry all my working life, we are used to the 400Hz used on aircraft supplies, and they go even faster than your utility trucks.
Which might explain the hyper-speeds I tend to reach on my FJR.

And I've seen some very strange explanations of electric motor behaviour, some of those here ought to be posted on the first day of April. I'm keeping out of it.

 

[yamafitter]

And I've seen some very strange explanations of electric motor behaviour, some of those here ought to be posted on the first day of April. I'm keeping out of it.

We could have had a lot of fun with that being that it is dog-pile Friday.

 

[RaYzerman19]

The technical stuff is all good after you identify the problem........ follow the money...... try these steps.

Assumptions - Ignition switch, kill switch and cable connection at starter motor are OK (for the moment), and all battery/starter relay connections are clean and snug.

Also assuming you know how to handle jumper cables safely, proper polarity, and securely without letting a lot of smoke and sparks out of stuff.

Get known good battery with jumper cables, hook up and attempt start. Use your car. Any significant difference from your fully charged bike battery?

Remove trigger wire from starter relay and apply 12V from known battery to starter relay connection. Eliminates ignition switch/kill switch as the issue if problem is still the same.

They make switches for this...... Take positive jumper cable and put hard on starter side of starter relay (sparky hazard, similar to the screwdriver method). Slow spin problem fixed? Get new starter relay (you likely need a new one anyway).

Or take a known good one off your lawn tractor as a temporary test slave, or if you have one off an old Ford......... wire it up temporarily on the bike for a test. Problem fixed? Get new starter relay.

Or opt out and get a new starter relay anyway.

Not fixed, check clean and snug battery cable connection at starter motor and retest with all known good stuff aforementioned.

Not fixed? Have a cold beer and swear a lot. Major surgery to remove starter motor............

 

[Sparky.88]

Wow... Lots of good discussion. Some of the techie stuff made my head hurt. I think I just need more coffee.

So far I've simply removed the battery and had it load tested. It tested out fine. I checked out connections at the battery and relay; no apparent issues there either. So I guess I'm moving on to the relay / starter switch next.

My biggest problem in troubleshooting further is that the issue is sporadic. It may happen once every couple of weeks. So running through further troubleshooting steps may yield nothing significant unless I happen to hit it at the right moment.

BTW - RaYzerman19, very nice troubleshooting procedure you outlined above. Thanks!

Given the age / mileage of the bike (2004 with about 30K miles) I may end up replacing the relay as preventive maintenance even if it seems to be OK. Given the sporadic nature of the issue, and after working my way through everything else, I'll probably give it some time prior to attacking the starter. Maybe a bad connection / component somewhere along the way is still the culprit even if not readily apparent.

Thanks again for all the advice. Much appreciated.

 

[Donal]

Wow... Lots of good discussion. Some of the techie stuff made my head hurt. I think I just need more coffee.
So far I've simply removed the battery and had it load tested. It tested out fine. I checked out connections at the battery and relay; no apparent issues there either. So I guess I'm moving on to the relay / starter switch next.

My biggest problem in troubleshooting further is that the issue is sporadic. It may happen once every couple of weeks. So running through further troubleshooting steps may yield nothing significant unless I happen to hit it at the right moment.

BTW - RaYzerman19, very nice troubleshooting procedure you outlined above. Thanks!

Given the age / mileage of the bike (2004 with about 30K miles) I may end up replacing the relay as preventive maintenance even if it seems to be OK. Given the sporadic nature of the issue, and after working my way through everything else, I'll probably give it some time prior to attacking the starter. Maybe a bad connection / component somewhere along the way is still the culprit even if not readily apparent.

Thanks again for all the advice. Much appreciated.

That doesn't sound too good to me............ The sporadic nature of the fault kind of points to a starter motor problem. If you have a commutator (mechanical switch) problem or a faulty winding then depending on where the motor happens to stop turning, you could have a problem if it stopped at the faulty area or no problem if stopped elsewhere (think of a roulette wheel). The odds are in favour of no problem.......................

If I were you I would keep an eye on E-bay for a replacement just in case. Or even better there was one available on here for $130 +shipping.

 

[bramfrank]

I went through the same issues a few months ago and it turned out to be the battery (actually 3 bad batteries in a row) - but not before I bought a low mileage replacement / used starter on line. So it sits in my garage, looking for a a bike to move in with.

It CANNOT be the relay. The relay cannot cause excessive drain, it can only reduce the current flowing to the starter motor, so while it might not crank with a bad solenoid, the dash would not reset.

If you want my starter motor you are welcome to buy it for the price I paid ($130) plus the actual cost to ship from 12901 (or from Montreal, if you happen to be in Canada).

Edit: Just noticed the promo from Donal AFTER clicking the submit button. Thanks

 

[Fred W]

I agree with bram. If you are going to shotgun parts at this intermittent issue, get yourself a good quality new battery. The load test is nice, but the FJR has been known to have issues with batteries that tested OK.

The reason it would only show up intermittently is that the load on the battery is higher on a warm / hot engine for some unknown reason.

 

[FJRay]

I agree with bram. If you are going to shotgun parts at this intermittent issue, get yourself a good quality new battery. The load test is nice, but the FJR has been known to have issues with batteries that tested OK.
The reason it would only show up intermittently is that the load on the battery is higher on a warm / hot engine for some unknown reason.

That is exactly the way mine lacted years ago. Battery was the cause then. Eight years later it was the starter but I changed the battery first to be sure and eight years on the battery was enough. The old one still works good in my mower.

 

[Sparky.88]

Donal - You're probably right. Wishful thinking, I suppose, that it's something simpler. Thanks very much for the lead on bramfrank's used starter.

Bramfrank - I just replied to your earlier post about your starter (before I saw your reply here). I may be in need of it. I'm also running a Motobatt for the first time; it's only a few months old. But based on your repeated bad experiences with that brand, I'm wondering if I can't really rule out the battery yet as the culprit.