C
I would take you up on that. ive got a multimeter but nut the fancy ones with the clamps on the top.
Lead Acid or Lithium Snow bike Battery?
- Thread starter RmK8oo
- Start date
I would take you up on that. ive got a multimeter but nut the fancy ones with the clamps on the top.
Ok, the voltage drop is the best way for checking resistance in those circuits and can be accomplished with your meter. You want the meter set on a low dc volt scale 0-20 dc volt scale, meters differ it can 0-10, 0-15, 0-20, 0-40. You are going to be testing for tenths of a dc volt, hopefully. What your going to do is make the meter an alternate path for the current to get to the load which is the starter. You don't disconnect any of the bikes wires for this test. What you do is hook the red wire/clamp of the meter on the positive battery terminal. Then hook the black wire/clamp from the meter to the terminal on the starter where the positive battery cable attaches, not to the body of the starter, but to the insulated positive terminal. So now the meter is in parallel with the bike's positive circuit (wire) that provides current to the starter. It originates at the battery and terminates at the starter just like the circuit you are testing. Now when you engage the starter and start to draw current the current has two paths to take to the load (starter motor). Hopefully all the current goes thru the bikes circuit and nothing thru the meter and the meter shows no voltage, but there is always some resistance in that circuit so you will see some voltage on your meter. Not being familiar with all your connections and wire size I would be happy with a few tenths of voltage showing on your meter. What this tells you is how easy it is for the current to flow to the load. If there is a problem, high resistance, bad connection, bad contacts in starter relay it will show up as voltage on your meter. If when you engage the starter and crank the engine 1 volt or more you have a resistance issue that is limiting current to your starter. The more voltage drop (higher the meter reads) the higher the resistance in that circuit. Ideally the meter shows a tenth or two. You should do the same test on the negative or ground side of the circuit. For that test hook the red wire/clamp from the meter to the grounded body of the starter. That connection can be one of the starter bolts. Then the black wire/clamp of the meter is hooked up to the battery negative terminal. Now the meter is in parallel with the bikes negative/ground/return circuit and provides an alternate path for current. If the bike's circuit has resistance that impedes current flow it will show as voltage on the meter when the engine is cranking. Again, less is better. If you find a couple tenths of a voltage on your meter it tells you the circuit is ok.
You can also check for a draw on the battery with that meter. If you disconnect the positive cable from the battery and put the meter in series, the meter is now the only path for current to flow. To do that, disconnect the positive cable from the battery, then hook the red meter wire to the battery positive terminal and the black meter wire to the cable that you disconnected from the battery. Don't allow that cable end to touch the battery terminal during the test. Do not attempt to start the bike or turn anything on while the meter is hooked up this way. Depending on what scale your on could burn fuse or damage meter. Hooked up this way you will probably see A few volts as I believe the ecu draws mila amps even with all switches off, mine does. That test would be with the meter in a low dc volt scale. If you see battery voltage 12-13 volts, with everything turned off you have a draw. My ktm showed 6 volts when I tested last year. I attribute that to the ecu and it has not caused a discharged battery on my bike. If the meter shows no voltage you do not have a draw. If the meter shows voltage try a current/amp test. With the meter still hooked up you can check for how much current is flowing if you have a dc ampere scale that reads low current. Flip the meter to the lowest dc amp scale on the meter. The ecu might draw a few milla amps, but ideally the draw of the ecu is so little that your meter shows nothing/0. Even high milla amps or fractions of an amp draw will reduce battery output in a few days.
It is easier than it sounds with all these words. Just go step/sentence at a time and should be good. Record your results so you can compare to ktm spec if they are available. Good luck. Questions are welcome.
C
awesome, thank you so much for taking the time to write that up and explain step by step process.. just what I needed. I will tinker with that later this week and report back all my findings. thanks again, I owe you a beer for that one!!!!
why am I only seeing 13.0 volts at my max, ever. when boosting and when running it hard and the stator is working its hardest, it never goes above 13.0. its a rewound stator from Baja Designs too thats like triple the output.
why am I only seeing 13.0 volts at my max, ever. when boosting and when running it hard and the stator is working its hardest, it never goes above 13.0. its a rewound stator from Baja Designs too thats like triple the output.
Cory, while the engine is running with a charged battery and all loads turned off you should have 14 to 15 volts at the battery. Generally, that voltage amount is controlled by the voltage regulator. The regulator controls stator output by limiting output voltage. When current (amperage) output of the stator exceeds the load, voltage will climb in the system. When voltage gets to the set point of the regulator, the regulator will bleed off the extra output to ground. This limits the output to acceptable voltage levels. So, if you only have 13 volts in that scenario, ( engine running battery charged, no load ) then most likely the regulator is at fault. Another scenario explaining the lower voltage would be if the stator output was not adequate to meet the load, or stator output was being bled off by an output wire from the stator to the regulator that was contacting/shorting to ground. Also, if those connections (from stator to regulator) have resistance that will limit stator output. If those wires and connections have no resistance and are not grounding out then the regulator is defective and limiting stator output by the lower voltage limit. It takes more than 13 volts to charge a battery efficiently and the stator produces more current at the higher voltage.
I'm not certain from your question, do you only have 13 volts with the charger attached to the battery?
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I just want to say dooman, you are very knowledgable and I also thank you for all this information! I also have starting issues on my bike and I am going to do these tests.
Cory, I think we might have a similar bike. I have a 2014 sxf with a 520 kit and Pr2.
Cory, I think we might have a similar bike. I have a 2014 sxf with a 520 kit and Pr2.
What was the temperature when you started it?
And how are you measuring voltage? With a meter directly on the battery posts or relying on the voltage reported by a trailtech gauge or similar?
Yeah, good question. I assume your directing it to Cory. Yes, voltage at the trail tech could be different than at the battery depending on how it, the trail tech, is connected. Best to check the charging voltage at the battery.
Allhatnocattle, thanks. If I can help, happy to do so. It has been nearly 40 yrs since I was in a classroom instructing and at the top of my game but, I recall some of it. Btw, knowing the current draw of the starter can be very helpful in solving the puzzle.
What are your symptoms of your starting issues?
Yes, was directed at cory and was in addition to "needpower's" question about starting temps.
Cory, I've experienced gauges, with long runs of small gauge wire, showing a reduced voltage due to voltage drop. Usually not severe enough to drop an entire volt or more, but if one is making the effort of a thorough troubleshooting, you want good data. Measuring voltage, of the running bike, directly at the battery will give you the most accurate data.
I believe you mentioned you've had ongoing issues with many different batteries so I have a hunch dooman is onto your problem of a voltage regulator issue which would never get your battery topped off. Or your aftermarket stator has a problem. Both would present themselves as a bad battery as you are never replenishing it fully so your state of charge is low. The faulty/worn out starter also presents as a weak battery and if your engine-on voltage is adequate and eliminated as an issue, then the recommended starter tests are next.
Keep going with your diagnostics and you'll find the issue. Be sure to share what you find.
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My issue is that it just takes a LOT of turning the bike over to get it going. The colder it is, the worse it gets, but really even when in a warm shop it takes a lot of cranking to get the thing to start. When it is cold I usually kill the battery and have to get a boost. Eventually it starts.
I have already ordered the starter clutch thing Cory linked a video to above. Maybe that will help. I am also going to use your test to see if something is causing a big draw on the starting system.
Is it turning over at full speed when warm in the shop and the summertime? If it takes a lot of full speed cranking, have you done a valve check lately and other tune ups? A bike that needs maintenance and doesn't like to start when its warm out will be a real bear in the cold.
If it's turning over slow when in a warm shop or summertime, then yes, you'll want to check several of the things mentioned here regarding checking starter and voltage drop and battery state of charge, etc.
I would be surprised if that starter clutch made a difference as long as yours is not slipping, and I think you would feel or hear that. That starter clutch is a mechanism that engages and allows the starter to rotate the crank and when the engine starts and turns faster it free wheels and allows the crank to spin without spinning the reduction gears that connect the starter drive to the crank gear. It is also called a one way clutch.
So why does it eventually start? What changed with all the cranking? It probably does not increase in cranking speed, air intake doesn't change, fuel delivery could change, timing stays the same, we create some heat with cranking so that could help. For good starting we need fuel, air, a spark and compression. Which of those is most impacted by cranking? Have you checked the plug to see if it is getting fuel after a few revolutions? Should be able to smell or see fuel on plug. I'm assuming you have changed the plug. If it is getting air, fuel and assume timing is not changing, that leaves compression. I think all the cranking could raise compression and help the starting especially if It had low compression/excessive blowby to begin with. You did not mention but, I bet it starts ok if only shut down for a few minutes. If initially it does not have adequate compression, cranking will raise compression by warming the piston and cylinder slightly, and more likely cranking distributes a bit of oil around in the engine and some off that oil makes it to the cylinder wall and assists in sealing a worn/leaking cylinder raising compression to the point it starts. So a compression or leak down test might show low compression. It would be interesting to squirt a bit of oil in the cylinder, kick or spin engine a few times, plug back in and see if starting improves. That oil will raise compression if piston, rings or cylinder are worn.
Valve adjustment affects starting also, but I assume you have checked those. I believe that engine utilizes a decompression mechanism in the camshaft that holds the exhaust valve slightly off the seat up to a certain rpm. I believe it is designed to relieve a little compression during kick starting. If the starter wasn't cranking at high enough rpm, poor battery, heavy oil, cold, that decompressor could impact compression. If yours is a no kick start engine it may not have that decompressor.
Another thought, the ecu, fuel injection and ignition works best with adequate stable voltage. If you have a marginal battery and high current draw starter the battery voltage can drop enough to effect those electronics. But, I wouldn't think the extra cranking would increase voltage and improve starting, so doesn't fit the symptoms. But, With a volt meter on the battery and the engine cranking, battery voltage should not drop below around 10.5 volts. Higher is better. Good luck.
C
awesome, thanks for all the tips guys, this is turning into a very informative thread. lots of learning going on here im sure!!
I view my battery/charging voltage via the trailtech voyager, confirmed to be the same as a multimeter on the battery posts. it never goes above 13.2 ish volts ever, while running, while boosting, and while on the tender with the tender reading 100%. it could very well be my voltage regulator.... ive done some dumb things to it. I think the big booster we got has a 200 amp "super jump start mode" where it jumps up to 15 volts and 200 amps. makes the motor spin faster than ive ever seen but I dont think my electrical likes that
temp when I started bike was -2C or 25F. and yeah weve got the exact same bike. 13 450sxf with thumper racing 520bb with a pr2 tuner.
how can I test my voltage regulator?
and allhatnocattle: please post back what you find about that one way freewheel clutch in the starter assembly.... I was told mines on its way out and have put 10 engine hours on it since.
I view my battery/charging voltage via the trailtech voyager, confirmed to be the same as a multimeter on the battery posts. it never goes above 13.2 ish volts ever, while running, while boosting, and while on the tender with the tender reading 100%. it could very well be my voltage regulator.... ive done some dumb things to it. I think the big booster we got has a 200 amp "super jump start mode" where it jumps up to 15 volts and 200 amps. makes the motor spin faster than ive ever seen but I dont think my electrical likes that
temp when I started bike was -2C or 25F. and yeah weve got the exact same bike. 13 450sxf with thumper racing 520bb with a pr2 tuner.
how can I test my voltage regulator?
and allhatnocattle: please post back what you find about that one way freewheel clutch in the starter assembly.... I was told mines on its way out and have put 10 engine hours on it since.
Cory, read post 44 again. It contains info on determining if your voltage regulator is bad. Look over the wires from the stator to the regulator before buying one. Do you have one off a buddies bike to test. The regulator must be grounded/mounted to function properly. 13.2 on tender would be ok. Should be above 14 on the bike running. Last couple I checked were around 14.7 volts.
Did you have the issue before the stator change? As mentioned in post 44, a weak/defective stator could explain the low voltage also. You could call the manufacturer of the stator and ask their procedure for testing their stator. If the stator is good and wiring ok it's the regulator.
Did you have the issue before the stator change? As mentioned in post 44, a weak/defective stator could explain the low voltage also. You could call the manufacturer of the stator and ask their procedure for testing their stator. If the stator is good and wiring ok it's the regulator.
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Chadx and dooman92, appreciate you thinking about this issue. To answer your questions about this:
Speed of cranking: Honestly I think it sounds like it is cranking over quickly, but I couldn't say just by listening to it. It certainly doesn't sound very slow, especially when I have a full battery.
Valve conditions: I have checked my valve gaps and ensured they are all within spec. At the end of last year I had a catastrophic failure because of something I did (I wont bother getting into that now) and the valves hit the piston. I have now had the head rebuilt and new piston. The valves are within spec and it still does it
Starter clutch: No I don't have any real reason to believe this is it. I had this off recently and I looked at it (not terribly carefully) and it seemed fine. The only reason I bought a new one is because I am throwing everything at the problem these days
Compression/Leak down: As mentioned I have had two different pistons in the bike since I went 520. I have done a leak down on both and the percentage is a little higher at around 13-14%. With the first piston I checked it and was concerned and called the guy who sold the kit to me and he said that was normal for this big bore kit to have that much blow by. When I replaced everything recently I decided to do a leak down on the fresh motor just to see and it was exactly the same blow by as the first piston. I had the rings professionally filed by a machinist to give me the correct ring end gap.
Honestly Dooman, I am wondering if you are onto something when talking about the compression. It seems like it needs cranking time to get something into the cylinder, whether it is fuel or oil to increase compression I am not sure... but perhaps this is it.
Does it start good once it is warmed up: Yes, actually it starts great. Better than most peoples bikes, as I can often start it in gear. Other guys I ride with say they have to be in neutral to start their bikes.
Cory: The other thing I noticed is I think this all began when I went big bore. I had a PR2 on the bike when it was a 450 and I never had any issues. Once I went 520 I think that is when my starting issues began. I even took my PR2 off and sent it back to them for reprogramming. I wonder if it is the PR2 that is causing this.
The only other idea I had was to just bring ether/quick start for that morning start everytime. I know its not a great idea for the motor, but I was thinking about it. It seems like my bike just needs that first start before its fine. I tried it recently but couldnt get the ether into the intake with the filter in the way. Maybe I would have to take off the intake each time or something like that. You guys think that is a dumb idea?
Speed of cranking: Honestly I think it sounds like it is cranking over quickly, but I couldn't say just by listening to it. It certainly doesn't sound very slow, especially when I have a full battery.
Valve conditions: I have checked my valve gaps and ensured they are all within spec. At the end of last year I had a catastrophic failure because of something I did (I wont bother getting into that now) and the valves hit the piston. I have now had the head rebuilt and new piston. The valves are within spec and it still does it
Starter clutch: No I don't have any real reason to believe this is it. I had this off recently and I looked at it (not terribly carefully) and it seemed fine. The only reason I bought a new one is because I am throwing everything at the problem these days
Compression/Leak down: As mentioned I have had two different pistons in the bike since I went 520. I have done a leak down on both and the percentage is a little higher at around 13-14%. With the first piston I checked it and was concerned and called the guy who sold the kit to me and he said that was normal for this big bore kit to have that much blow by. When I replaced everything recently I decided to do a leak down on the fresh motor just to see and it was exactly the same blow by as the first piston. I had the rings professionally filed by a machinist to give me the correct ring end gap.
Honestly Dooman, I am wondering if you are onto something when talking about the compression. It seems like it needs cranking time to get something into the cylinder, whether it is fuel or oil to increase compression I am not sure... but perhaps this is it.
Does it start good once it is warmed up: Yes, actually it starts great. Better than most peoples bikes, as I can often start it in gear. Other guys I ride with say they have to be in neutral to start their bikes.
Cory: The other thing I noticed is I think this all began when I went big bore. I had a PR2 on the bike when it was a 450 and I never had any issues. Once I went 520 I think that is when my starting issues began. I even took my PR2 off and sent it back to them for reprogramming. I wonder if it is the PR2 that is causing this.
The only other idea I had was to just bring ether/quick start for that morning start everytime. I know its not a great idea for the motor, but I was thinking about it. It seems like my bike just needs that first start before its fine. I tried it recently but couldnt get the ether into the intake with the filter in the way. Maybe I would have to take off the intake each time or something like that. You guys think that is a dumb idea?
C
going to tinker with this today! ive never seen 14.7 volts unless its hooked up to the giant car starter and I got the car starters dial in max mode.
wires from the stator to regulator are fine. I do not have one from a buddies bike. they do seem fairly cheap though.
yes I had the issue before the stator change.. thats one reason I went with the bigger stator. I thought it wasnt charging the battery enough, but I guess it was and it was other problems I had. ive had 3 new batteries, a brand new LI ION tender, a brand new xp-10 booster pack that should start a damn kenworth, I ripped ALLLL the excess wiring off my bike and threw everything out. headlight, heated grips, custom switch panel. all gone.
she still wont start in the mornings. same problem as allhatnocattle. I was wondering about BB increasing compression too. my bike also starts amazing when warm... that 360CCA battery spins it like its red lined and it fires up in one revolution it seems.... but cold, it just spins and chugs sluggishly.
this will be the last big bore kit I ever own thats for sure.
I did call Baja Designs and tested the stator when I got it back from them, it all tested out good.
from Baja Designs: "You can check the power coming out of the stator by setting your multimeter to AC voltage and putting the probes on the yellow leads. It’s hard to say what it’ll be at because it’s constantly fluctuating around the rpms of the engine. But it’s basically going to be increased as the engine runs. 90 watts will be at peak power.
" A healthy stator should be sending out about 13.5 volts to 14 volts when the bike is running "
Allhatnocattle, if I was working on that bike I would do that oil in the cylinder trick. It can be two stroke, 0w20, 5w30 etc. That oil will help seal up worn rings, excessive ring end gap etc. Imo, the larger the piston, with the very short piston skirt, the more likely it will rock in the bore and loose ring seal. Imo, ring end gap is critical to low rpm compression. Ktm oem rings are very thin ( less than a mm thick) for this reason and they maintain seal better than a thicker ring. Any idea what rings are in it and what the end gap is/was? If that thing starts better with a few drops of oil in the cylinder your issue is starting compression. Put enough oil to seal the gap between the top of the piston and the cylinder wall, about a tablespoon/1/2 oz or so, turn the engine over with the plug out a few times to distribute the oil in the cylinder, plug back in and start it. More oil is not better as you have limited volume at tdc and we can't compress oil so something breaks
Btw, not a fan of starting fluid. Starting fluid is sometimes a band aid to low compression.
Btw, not a fan of starting fluid. Starting fluid is sometimes a band aid to low compression.
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Dooman, I am wondering if you can help me a little more. I tried your procedure to test the voltage drop. I set my multimeter up as you described as an alternate path from the positive battery terminal to the positive connection on the starter. Without hitting the start button my MM already was reading 13.25. This made me nervous that I was doing it wrong and so I disconnected it without hitting the button.
My MM is an Innova 3300 and I have it set to "10 megOhm Input Impedence, at the setting of 20. Is that right?
www.canadiantire.ca
My MM is an Innova 3300 and I have it set to "10 megOhm Input Impedence, at the setting of 20. Is that right?
Innova 3300 Digital Multimeter | Canadian Tire
Innova 3300 Digital Multimeter can safely and accurately troubleshoot a variety of automotive and household electrical problems | Canadian Tire
www.canadiantire.ca
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Ok I will try that next. I don't recall exactly what my ring end gap was, but the first piston I put in I did it myself with a dremel. The second one I thought maybe my ring end gap was the cause of my starting issues and took it to a proper machine/engine shop who has a proper ring gap machine. He put it to the "smaller end" of the spec, as per my request.
My leadown test results were the same with the old piston and the new one, so I dont think its ring end gap.
I know ether is a bad solution. All my buddies will bug me, and I will never hear the end of it. To be honest though I don't even care, I just want the bloody thing to start in the morning. I stress about it the night before the ride, all the way there and fret about it when it wont start. When it finally gets going it is a relief, but I am tired of the fight.