Bike doesn't start in cold weather

The good news is no, you never really do.

If it's a cheap digital Harbor Freight (etc.) type voltage meter, it will not be absolutely accurate nor resolve properly down to hundreth's of a volt. So even a small variability (+ or -) can translate into large "ranges" in readings even though the underlying true voltage may be the same. Voltmeters can also exhibit further inaccuracy (beyond their inherent base level of inaccuracy) when the temperature of the device changes significantly, so if you had anywhere near heat (i.e. the engine, hot LA sunlight, etc.) that will also affect the seemingly incomprehensible readings.

On the other hand, something might be screwed up in your electrical system.........

 

Agree 100% with five of a kind your charging system is functioning correctly , before you spend a bunch of money .

 

When you refer to the fuse holder are you referring to the fuse box? I did replace the fuse box with the blade style fuses and that didn't really do anything. I've looked over the article you gave me a couple of times as well.

 

Rode the bike immediately after taking it off the charger. Yes," full charging capacity" meant "maximum charging voltage output" and it read as high as 14.82 but it bounced around a bit. I'm just saying that's the highest it got.

 

It's functioning but I wouldn't say, "correctly".

Josh

 

have you gone through the tests listed in the link I provided above?

post your findings


this thread may help you

https://www.xjbikes.com/forums/threads/battery-charging-problem-alternator-rotor.119858/#post-601814

 

colud be your battery is bad even at 1 year old

How do I know if my battery is good?:
https://www.xjbikes.com/forums/threads/the-ultimate-relay-switch-sensor-and-diodes-guide.27543/
1) with the engine and all electrical accessories off, the battery should read a minimum of 12.8 volts DC. If not, the battery is either not fully charged, or it is bad (it is incapable of holding a full charge). Charge the battery fully and check again; if the reading is less than 12.8 volts, the battery is bad and should be replaced.

 

Charging System Tests:
For all XJ-series models, the maximum available charging output VOLTAGE should be as follows (all values are approximate):

* approximately 500-2000 rpms: 1.8 volts gradually increasing to 14.2 volts
* 2000+ rpms: 14.2 volts up to about 14.8 volts, with a maximum of 14.8 volts (all models except XJ700-X and XJ750-X)

If your charging voltages are too low, suspect the alternator brushes first, then perform the alternator stator and rotor checks as described in the Alternator Section.

your numbers are low .......... time to do more tests

 

Not to beat this issue to a pulp but is it possible that excessive heat can inhibit the functionality of the alternator stator? I guess I never noticed this before but when I first turn on the bike the charging system works great. I'll rev the engine up to 3000rpms and the voltage goes up to 14.5volts no problem. However, after I've been riding for maybe 10 minutes or so the old problems come back and it can barely get past 13volts again even at 4000rpms.

 

It's possible, heat can cause things to expand and compromised coil wires to short/go open. Only way to tell for sure is run through the FSM test procedures cold and once again after you warm it up. The faulty part will read differently for the tests.

 

test spec
* 2000+ rpms: 14.2 volts up to about 14.8 volts, with a maximum of 14.8 volts (all models except XJ700-X and XJ7 l50-X)

heat is caused by current draw you need to make sure ALL your grounds are clean and tight.
motor ground, frame ground from motor ground
frame ground at the ignition coil
and battery connection.

you need to do the same to the positive connections as well.

clean the copper rings with an hard art eraser then spray the crap off with electronic cleaner.
measure the brushes, check the brush holder

then ohm out the charging system if you post your results we can help you better.

are you running any extra electronics on the bike?

 

take two aspirin and call in the morning

 

Where are the grounds located?

 

negitive battery terminal (ground) follow wire to motor bolted to motor (ground) follow small wire up to battery box lower left corner screw is where this ground is attached to frame.
go to ignition coils you will see a black wire with ring terminal attached to the mounting bolt (ground) the4re may be 2 one on each coil.

 

Heat=resistance

 

Ok, I'll look for these. Thanks.

 

My 81 550 Seca won't start on cold weather mornings/evenings. Turns over fine but won't start even with the choke on. This morning in particular was 47 degrees and the battery was fully charged up. No start. The bike starts perfectly every other time. If it doesn't start in the morning I'll try in the afternoon and it starts right up. I thought it might not be getting enogh gas so I put the petcock on PRI and that didn't work. One evening I had a friend help me push start and after about 3 attempts it almost worked and then I just pressed the starter and it fired right up. Anybody have any ideas? It has brand new plugs. I have to admit I don't use the recommended oil. I use 20w-50 and it's suppose to be 20w-40 and I heard oil viscosity can be a factor. Also, the PO had changed the jets from the original stock 112.5 to 115 and I had changed them back to the stock 112.5 during my last carb rebuild. Maybe he was onto something and I should change it back? The bike does pop a little when I slow down and I heard that can be due to a lean condition which could also be the reason for not starting. If it is due to a lean condition would it help to just open the pilot screws a bit and/or change the jets back to the 115's? Thanks

 

http://xjbikes.wikidot.com/carb-specs

pull the headlight fuse to stop headlight from coming on.
the xj550 do not like the colder weather, a shot of starter fluid should do the trick shoot it into the air box. but 47 degrees is not that cold
it may be time to get new ignition coils have you replaced the spark plug caps?

20w 40 oil change to that

the pilot jet is what starts the bike not the main jet. main jet comes into play around 2 to 3k rpm
set the choke do not touch the throttle at all when starting the bike

when the main jets were changed was the Main jet NEEDLE matched to the jet?

did you get the enrichment wells in the carb bowls clear when you cleaned the carbs? how about the tubes that go into the wells?

 

cold blooded at first - then pops warmed up

when the bike starts how does it act?
you go for a ride and the idle stays with in spec? or does the idle end up climbing up?
a vacuum leak will make the bike hard to start is your vacuum hose new and vacuum line?
does 15 minutes out in the sunshine make it start?

do a voltage drop test see what the voltage drops to when pressing starter button

 

Please, please, please stop making a new thread for every problem. That makes it really difficult to give you the best help.

5535606
All about the same bike, and many without responses about what you did after recieving advice.
We covered this problem before. Please get back to us about what you do from this point on in this thread.

 

Sounds like your fuel enrichment circuit is possibly gummed up . Short of pulling carbs and float bowls to clean out jet try this . Give your carb a "HOT SHOT" drain all 4 float bowls, prop tank up and pull fuel line off of petcock . Obtain a large meat baster , fill with a 50/50 of acetone and Berrymans B12 carb cleaner squirt this one the fuel line several times , let this sit for about 30 minutes. Drain all 4 float bowls, put fuel line back on petcock , set to PRI set chock to on see if bike starts better , one other item set to full chock make sure cable is fully pulling up plungers on carbs. It is possible this could be a cause of hard starting .

 

Thnnk

Thanks for the advice but I don't want to have to pull the headlight fuse or spray starter fluid every morning or whenever I'm stranded to start the bike but I agree, 47 degrees is not that cold and it's interesting that you mentioned the coils. I haven't replaced the caps but two of them accidentally came off from me pulling them off the plugs too hard and when I looked inside it was brown and rusty so I'm not sure if I should just replace the wires and caps or the whole coil. As far as the carbs the main jet needle was not matched. I didn't know you had to do that. I'm also not familiar with what enrichment wells are or the tubes that go into the wells I simply opened them up and cleaned the crap out of everything and put it back together. Took me two days.

 

The bike sounds pretty dam good when it starts. Idles nice after when I'm out on a ride. Idle does not continue to climb up. I checked for vacuum leaks a while ago and that hasn't been a problem but I haven't tried starting the bike after 15 minutes in the sun just later in the afternoon and it starts up nice. Could you explain the voltage drop test? Thanks.

 

Sorry about that. I thought that's how this forum works. New problem new thread. I will stay on here for now on.

 

Thanks for the advice.

 

My other problem on my bike which may be related is the weak charging problem. Here's what happens: when I first start the bike and ride it the bike charges up to 14.7 volts just fine. HOWEVER, after riding for maybe 15 minutes the charging starts to get weaker and weaker to the point where it can't charge past 12.5volts at 3000+rpms. After my ride today I measured the charging voltage and at idle it measures around 12.11volts which is fine but it still won't go past 12.5volts when I rev it to 3000+rpms. Keep in mind, however, that there have been instances the bike has NOT been able to start in the cold weather on a fully charged up battery and other times it has started just fine in the afternoon on a basically weak battery. The more I think about it I'm wondering if the coils are to blame. I looked at them today and cleaned the heck out of the ground connections and what not and nothing has changed. This has been the main problem with this bike since I bought it a year ago. I have changed the brushes, regulator, the slip rings on the alternator coil are smooth I've cleaned all the connections, changed to a blade style fuse box and host of other things. Any input would be great. Thanks.

 

Relax your charging system is working, if you rode for 2 hrs and your bike quit and battery went flat then yes it would be a problem . Look if your charging system put out 14 volts constant you end up boiling your battery. The charging system will shed some of this voltage so battery stays around 12 to 13 volts. Your problem of hard to start when temp is low is carb related it is NOT CHARGING PROBLEM....you are shot gunning a problem that does not exist.

 

Could you point me to some literature that explains that? I honestly want to believe you but what's contradictory is that nothing in all the literature I have read says what you're saying. If something literally said, "when you first ride your bike your charging system will be charging at 14.5volts and then after a while will gradually lower down to 12.5volts" then I could relax but all the literature I have read in the manuals and everywhere else simply says that at 3000+rpms you should be reading a charging voltage of 14.5volts, that's it.
As far as the carbs I'm going to try your HOT SHOT technique but keep in mind I don't have a problem with starting MOST of the time. It just seems when it's on the colder side out that it doesn't want to start. I don't have a garage so my bike is outside all the time. All I can do is cover it.
I'm also a bit curious about the whole ignition coil assembly, wires, and plug caps. I didn't know there was a resistor in the plug caps and that those can get old and need replaced. I have noticed that when I first ride my bike it has a lot of zip but after about 15 minutes of riding it starts to become sluggish. This was also one of the reasons I was questioning the charging output. It's not night and day but I do notice a difference. So, I"m questioning the resistors in the plug caps as XJ550H suggested. In the past year (and before my carb rebuild) I had situations where I wasn't getting any spark on a fully charged battery. I also read this today in the XJ parts catalog:

Voltage at coil positive input terminal (the red wire with the white tracer stripe) with the engine running: 12+V This measurement should be taken at the back of the connector shell (stick the volt meter probe in thru the back of the connector) and the battery negative terminal. Compare this reading with the measured battery voltage (voltmeter connected between the battery negative and the battery positive terminals). Any significant difference or lack of voltage indicates corroded or broken connections in-between the fusebox and the ignition coils, and reduced voltage at the coil input will result in reduced coil output (at the spark plugs). Although reduced voltage input (and thus less coil output voltage) may not significantly affect engine performance once the engine is warmed up, it can and will result in "hard start" situations when the engine is cold and/or when the choke system is engaged (since richer fuel mixtures require a much stronger spark to create ignition of the fuel mixture).

In any case, like I said the bike starts 9 out of 10 times and I only notice hard starting in colder weather. Thanks for your help.

 

this link has info on charging system
The Ultimate Relay, Switch, Sensor, and Diodes Guide

good reading
TALKIN' TECH: Various thoughts on various issues

this contains lots of info
The Information Overload Hour


voltage drop test
connect meter to battery read voltage. press starter button to see where the voltage drops to when trying to start bike anything below 10 volts tci will not fire and bike will not start.

 

Again use the KISS principle Keep It Simple Stupid , if bike seems sluggish after it heats up points more to CARBS , more than anything . As to your coils 81 to 83 CB 750 Honda coils will swap in and have replaceable wires , can be bought NEW from Cycle Recycle Part 2 40$ each. Inspect your coils are there any cracks in housing ? If you do try these could desolder lead off of old Coils and crimp me connector leads on . As I stated your charging system is WORKING leave it alone , if it was not after about a hour your bike would shut down , your electrical system would only be running on battery power when it drops below 11 volts TCI will shut down. Once I had a mint 82 CB750 custom with 4500 miles, was riding it home from dealer I bought it from , 2 miles from home bike died. Had to pull battery and charge it for 10 minutes and made it another mile , recharged made it home . The charging system was OUT common on Hondas of the vintage as I found out. Replaced vantage regulator still no joy, was ready to try stator, owner of Cycle Recycle Part 2 said it was the rotor , he was right , charged at 13.5 volts , before read 12vlts which was simply the battery voltage. My point of what happened with my Honda the charging system was INOP . Yours is working from what you describe.

 

Update. I just did a diode check on the ignition coils and I'm getting zero. I pl

Okay, if it's working it's working. What I don't understand though is that if the battery reads 12.8 volts before a ride and then I get back and it reads 12.2volts it seems to me that that is not a working charging system. It seems to me that a correct charging system should always keep the battery fully charged but I am still learning about these early 80's bikes and maybe that was the norm. I don't know anymore.
As far as the coils I just did a diode check and I literally got a 0.00ohm reading. I set the meter to ohms 20k and put the two leads into both primary sides. The reading starts at OL and then when I apply the leads it literally says 0.00. I then tried to do the secondary lead reading and got the same thing. I wanted to make sure the meter worked correctly so I tried the diode check on a spare regulator/rectifier I had sitting around and it works fine. I've had no spark situations in the past with this bike so I'm guessing these coils are duds. By the way, I have never ridden more than an hour on this bike so there's that. I'd like to though.

 

By the way, I noticed that the right coil has this extra wire attached to it but the right one does not? (see pics) I couldn't find any dangling wires. Is this just another ground wire of some sort?

 

diode check? ignition coils are ohms tested

 

that's what I meant. I put the meter to 20k ohms and got 0.00ohms. Sorry

 

Here is the other picture of the other coil with the added wire that the right does not have. Sorry for not including this earlier.

 

That appears to be a main harness ground wire (black) and typically they are attached at the coil mounting bracket, but it has nothing to do with the coil(s) itself. The black wire comes out of the main harness and simply serves as a common ground for a variety of circuits on the bike.

You need an ANALOG (moving needle) volt/ohmmeter to work on these bikes. Some of the ohm measurements are way too small to measure with a digital meter (didn't we discuss this before?) . The ignition coil primary resistance, secondary resistance (without the plug caps on the end of the wires), and the resistance of each plug cap would be measured and compared against specs (P.S. specs are specified as being valid at about 70-F). And while you're at it, you should also check the resistance of the pick-up coils.

However, most of the issues that you describe probably have nothing to do with the ignition coils (there can be rare instance when the coils are breaking down as they heat up, but again.....that is rare). You either have fuel system or charging system issues, or a combo of both.

Checking alternator stators: the resistance across each pair (white1 to white2, white1 to white3, and white2 to white3) of the three white wires (white1, white2, and white3) at the connector should be as follows. These tests should be taken while the components are at a temperature of about 70-F:

0.50 ohms +/- 10% for all XJ550 models.


Checking alternator rotors: the resistance across the two lead wires (usually brown and green) at the connector should be as follows. Note that worn or damaged alternator brushes can affect these readings, as can "dirty" copper commutator rings on the rotor face (where the brushes contact the rotor):

4.5 ohms +/- 10% for all XJ550 models.



Checking pick-up coils:
650 ohms +/- 20% = 520 ohms to 780 ohms acceptable range for all XJ550 models.


Ignition Coils:

Primary side (input from main wiring harness):
2.5 ohms +/- 10% = 2.25 ohms - 2.75 ohms acceptable range for all XJ550 models.

Secondary side (spark plug wires, without their end caps):
11K ohms +/- 20% = 8,800 ohms - 13,200 ohms acceptable range for all XJ550 models.


Spark plug caps:
10K +/- 20% = 8,000 to 12,000 ohms per cap acceptable range for all XJ550 models.

Stock spark plugs:
0 ohms per plug for all XJ550 models.




There are two main types of alternator systems commonly used on motorcycles. Both types depend on a magnetic field, created by magnets in the alternator rotor, to induce an electrical voltage and current flow in a stationary coil of wires-----the alternator stator. If you ever get confused as to which is which, just remember that the rotating component is the "rotating rotor", and the spaghetti-like bundle of wires is the fixed-in-place, "stationary stator"......

The first type is the permanent-magnet rotor system (used on Virago, V-max, and FJR models, among others). In these systems, the fixed-strength magnets in the spinning rotor generate a constant-strength magnetic field, and thus excite the stator coil constantly; thus the alternator puts out 100% current at all times and the voltage regulator merely serves to shunt any excess generated current to ground. The advantage of the permanent-magnet system is a reduced amount of system complexity, but at the cost of increased heat and power losses (since the alternator system is generating power, and thus using up engine horsepower, constantly).

The XJ-series of bikes follows the more common automotive model, which employs variable-strength electro-magnets in the rotor. In these systems, the variable-strength magnets in the spinning rotor, when energized, are used to form the magnetic field which excite the stator. The voltage regulator controls the voltage output by varying the input voltage applied to the rotor's electro-magnets, and thus varies the strength of the magnetic field. If the system voltage drops, the voltage regulator increases the voltage fed into the rotor electro-magnets, thus increasing the strength of the magnetic field that the magnets produce, and therefore increasing the excitation (output) from the stator....and thus the alternator output voltage increases.

In both systems, the stator windings are 3-phase. Each stator wiring bundle (there are 3 of them, and each bundle is called a "leg") kicks out similar voltage, but 120-degrees out of phase with the adjacent leg(s). The resulting AC currents are then rectified (changed) to DC current via a 3-phase bridge rectifier, made up of 6 diodes, such that current in any leg flowing in either direction is directed back into the system as 12-volts DC (actually, around 13.5 to 14.5 volts DC, when everything is working properly).

If you lose a leg, or even a single diode, it is possible to still achieve voltage if the load is minimal, but as current requirements increase, the alternator will not be able to meet the challenge and the battery will have to take up the slack. Of course, as the battery drains, the available voltage is reduced, so the maximum rotor field voltage is reduced, so the current output is reduced, so the battery has to take up more slack, so ....

The end result is the battery discharges and the bike won't start.



There are a number of different tests that can be performed on the regulator and rectifier unit, and it is beyond the scope of this catalog to explain in detail what those tests are, and when and how to perform them. The regulator, in particular, stands "in-between" two of the main electrical components in the entire system----the battery and the alternator----and thus performance of those components must be evaluated before a faulty regulator is suspected. We strongly suggest the purchase of a factory or aftermarket service manual for your bike to be able to properly diagnose and perform electrical system problem solving and repairs!

 

Chacal, it turns out I was using my multimeter incorrectly. I was so excited I went and did a quick test just on the primary connections on the coils. Here are the results:
Left coil - 2.1o ohms
Right coil - 1.9 -2.10 ohms (this one bounced around a bit)

I didn't do the secondary side yet but I believe both of these results are below spec. Like I mentioned before my bike starts MOST of the time but the three times it didn't start this last week have been when the weather was rather chilly around 40 to 45 degrees. It never get's super cold here in LA but my problems seem to be in line with what the catalog on this forum says:

"Although reduced voltage input (and thus less coil output voltage) may not significantly affect engine performance once the engine is warmed up, it can and will result in "hard start" situations when the engine is cold and/or when the choke system is engaged (since richer fuel mixtures require a much stronger spark to create ignition of the fuel mixture)."

What do you think?

 

you should start by checking out your charging system. ohm it out. remove the cover for alternator to check the commuter rings for being clean and brush leangth to be in spec. clean all the connectors in the charging system . at the regulator at the battery make sure the grounds are clean and secure.

your charging system numbers are a little out of spec.
it could just be a bad battery no matter how new your battery is. the 14 volts should always be there at 2000 rpm.

 

I 100% agree. I just measured the stator and it read .2, .3, and .5ohms. It's the stator. It's always been. I just get too hung up about buying something else for this frickin' bike because I already invested way too much. What can you do. Also, the ignition coils read 2.1ohms on the primary side and I couldn't even get a reading on the secondary side. With or without the caps. Screw it. I'm buying new coils and a new stator.

 

I would continue to look at the entire charging system

 

before I buy a new stator could anybody tell me what the ac output should be at the three white wires coming directly out of the stator both at idle and at 3000rpms? I can't seem to find that anywhere. thanks

 

there is no spec in the manual for that.

 

Per Chacal, I bought an analog voltmeter but I got mixed results. It read 0.2 ohms across all 3 sides of the stator which is what my digital multimeter said. However, it also said 0.5 ohms on the primary side of my ignition coils but when I checked again with my digital multimeter it read 2.2ohms. Yes I cleared the analog to zero every time I used it and it still gave me this weird result. Anyway, I checked the coils again on the secondary side but this time I pulled the caps off and they all read above 8000ohms which is in spec so I can conclude that my ignition coils are fine. However, it's my plug caps that were funky. I could barely get a reading on two of them and the other two I couldn't get a reading on them whatsoever. Going to get some new caps.
It will be interesting to get a new stator on this bike. My charging system has been a headache for over a year now.

 

Quick question, I stumbled upon a used stator that reads 0.8 ohms on all three wires. Is that number unusually high? Is that a good stator?

 

specifications should be:

0.50 ohms +/- 10% for all XJ550 models.

 

I understand that but im curious if it consistently reads higher on all three wires is it still good? What does a high ohm reading on a stator mean?

 

it could be your meter, touch the probes together and see if you get a reading. could be you have loose plug ends that go into meter.

another problem with reading a coil of wire is the inductance caused by all that wire.

a good test for your meter would be get a few 1% resistors .5 ohms and read them see what you get.

.8 may be good as they all read the same but is a lot of work to find out.

 

So, I believe my hard starting issue was the fact that there wasn't any gas getting to the cylinders. What solved it was simply putting the petcock on PRI and usually after about 30 seconds the bike starts right up. I'm curious why the bowls aren't staying filled up?
I'm also getting some popping on deacceleration which I understand means I'm getting a lean mixture. I turned all the pilot screws another half a turn out which means all four of them are 3 full turns out now. As a result the bike idled higher which was solved by turning the idle screw down of course but I'm still getting the popping. Should I just keep turning the pilot screws out until the popping stops? Is it that simple?
Finally, I'm getting a slight hesitation when I open the throttle in first gear which causes the bike to sputter for about a second but then it catches on and runs good. I soaked the carbs in Berrymans to see if anything might be gummed up. Also, when I cleaned the carbs about 6 months ago the PO had 115 size jets and I put the stock size, 112.5, back on. I'm curious if I should go back to the 115's.

 

Did you have the entire rack disassembled with all rubber bits removed before you soaked them?