20 Most Recent 2001 Yamaha DT 125 R Questions & Answers


Hi, Adam before testing any electrical component in the Starting Circuit it is "IMPERATIVE" that you have a fully charged battery of 12.5 volts or more and be able to pass a proper "LOAD" test if necessary, you may have a preliminary reading of 12.5 volts or more but little or zero amperage, the battery is faulty and must be replaced. AGM type batteries fall into this scenario more so than lead-acid batteries.
1. Ignition Switch not in the "ON" position.
2. Engine Run Switch in the "OFF" position.
3. Engine Run Switch is "FAULTY" or corroded.
4. Check the battery terminals for damage or corrosion check the battery cables at "BOTH" ends for loose, corroded, or broken connectors, "INSIDE" and outside the cable harness, perform connector wiggle test and check cables with an ohmmeter.
5. Bank angle sensor needs a reset or is faulty.
6. FOB battery low or dead.
7. Faulty ignition switch.
8. Faulty starter button.
9. Faulty kickstand, clutch, neutral safety switch.
10. Security alarm needs a reset.
11. Starter relay, solenoid, starter motor or circuit wiring faulty.
12. Starter armature or field coils have failed.
13. Main fuse or circuit breaker may be blown or faulty.
14. Faulty ignition relay.
15. The electric starter is working but starter clutch has failed.
16. Check for engine trouble codes.
For more information about your issue and valuable "FREE" downloads that you will need for viewing or printing please click on the blue links below. Good luck and have a wonderful day.
Weird Electrical Fault Yamaha SR 125 Motorbike
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http://service.tanga-moteurs.ro/data/Yamaha%20SR%20125%20'97%20-%20Service%20Manual.pdf
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2001 Yamaha DT... | Answered on Feb 25, 2018


Hi, Samellis before testing any electrical component in the Charging System it is "IMPERATIVE" that you have a fully charged battery of 12.5 volts or more and be able to pass a proper "LOAD" test if necessary, you may have a preliminary reading of 12.5 volts or more but little or zero amperage, the battery is faulty and must be replaced. AGM type batteries fall into this scenario more so than lead acid batteries.
1. Battery Test:
The battery needs to be a fully charged and load tested to ensure proper readings, connections need to be clean and tight. If you are not working with a fully charged and functional battery, all other voltage tests will be incorrect. Standing battery Voltage should be 12.5-13.2 DCV.
2. Charging System Voltage Test:
Start motorcycle, measure DC volts across the battery terminals you should have a reading of approximately 13.2-15 DC Volts.
3. Connections and wires:
Inspect the regulator stator plug, and check the battery terminals for connection corrosion. If everything seems to be in order, move on to number 4 below to determine if there's a failed component.
4. Stator Checks/Rotor Check: Each of the following tests isolates the Stator & Rotor. If AC output and resistance test fail and stator test passes then the rotor is at fault (Pull Primary covers and inspect rotor for damage).
5. AC Output Check:
Unplug the regulator plug from the stator start motorcycle and change Voltmeter to AC volts. Probe both stator wires with your meter lead. The motorcycle should be putting out approximately 18-20 ACV per 1,000 rpm. Reading will vary depending on system, check service manual specification
Generic Specs:
22 amp system produces about 19-26 VAC per 1,000 rpm
32 amp system produces about 16-20 VAC per 1,000 rpm
45 amp system produces about 19-26 VAC per 1,000 rpm
Stator Resistance Check:
Switch your multimeter to Ohm x 1 scale. Probe each stator wires with meter leads and check resistance on the meter.
Resistance should be in the range of 0.1-0.5 Ohms. Reading will vary depending on the system, check the service manual for specifications.
Generic Specs:
22 amp system produces about 0.2 to 0.4 ohms
32 amp system produces about 0.1 to 0.2 ohms
45 amp system produces about 0.1 to 0.2 ohms
Stator ground Check:
Switch your multimeter to Ohm x 1 scale.
Probe each stator wire with your positive lead on the multimeter and the negative to ground.
There should be no continuity to ground on either wire.
If there is continuity your stator is shorted to ground and must be replaced.
5. Regulator Test:
Each of the following tests isolates the regulator only, so if any of these tests fail, the regulator is at fault.
Identifying Wires:
Battery Charge Lead- Wire going from regulator to battery positive.
AC output leads- Wires coming from the Stator to the regulator.
Ground- Wire from Regulator to ground or regulator may be grounded via the physical bolting to chassis.
Regulator Ground Test: Ensure the regulator body is grounded or grounding wire is fastened tightly to a good ground (you should verify this by checking continuity from regulator body to chassis ground).
Fwd/Reverse Bias Test/Diode Test:
This check is testing the Diode function to ensure it is regulating the AC current for the stator into DC Current.
Switch multimeter to Diode Scale.
Place your Multimeter positive lead on each AC output wire.
Place your multimeter negative lead on the battery Charge wire.
The meter should read voltage typically around .5 volts.
Next, switch your multimeter leads putting the negative lead on the AC output wires and the Positive lead on the Battery Charge Wire. The reading should be Infinite. With your meter on the same setting, place your multimeter positive lead on the regulator ground wire or to the regulator directly, and then place your meter negative lead on the AC output leads.
The meter should read voltage typically around .5 volts.
Next, switch your multimeter leads putting the negative lead on the regulator ground and the Positive lead on the AC output wires. The reading should be Infinite.
Note: Below is a table to show the readings:
Positive Lead Negative Lead Reading
AC output 1 Battery charge lead Voltage
AC output 2 Battery Charge Lead Voltage
Battery charge lead AC output 1 ?
Battery charge lead AC output 2 ?
Ground AC output 1 Voltage
Ground AC output 2 Voltage
AC output 1 Ground ?
AC output 2 Ground ?
For more information about your issue and valuable "FREE" downloads that you will need please click on the blue links below. Good luck and have a wonderful day.
DT125R Lighting Charging
http://racetechelectric.com/files/pdf/rte_troubleshooting_flow_chart.pdf
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OEM parts for Yamaha
YAMAHA DT125R Owner Manual

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2001 Yamaha DT... | Answered on Jun 17, 2017


Hi, Anonymous sorry you can't find the first and best tool you ever bought for your Yamaha despair, not for a mere $0 you can download another one. For more information about your issue and valuable "FREE" downloads that you will need please visit the websites below. Good luck and have a nice day.
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2001 Yamaha DT... | Answered on Apr 08, 2016


Hi, Weedman01604 motorcycle engine repair isn't rocket science or nuclear physics find a shop that knows what they are doing and has an excellent reputation for more information about your question and valuable "FREE" downloads that you will need please visit the websites below. Good luck and have a nice day.
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2001 Yamaha DT... | Answered on Mar 12, 2016


Hi, Max_hobbs for more information about your question and valuable "FREE" downloads that you will need please visit the websites below. Good luck and have a nice day.
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2001 Yamaha DT... | Answered on Mar 11, 2016


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2001 Yamaha DT... | Answered on Mar 11, 2016


Hi, Anonymous sorry you can't find the first and best tool you ever bought for your Yamaha despair, not for a mere $0 you can download another one. For more information about your issue and valuable "FREE" downloads that you will need please visit the websites below. Good luck and have a nice day.
http://www.motogelnar.cz/manual/YAMAHA/DT125X_RE-05-Service_Manual.pdf
OEM parts for Yamaha
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2001 Yamaha DT... | Answered on Mar 10, 2016


Hello,

If you have not done so, please check the fuel filter for good fuel flow. Also, pull the output hose off the fuel pump to see if it has good fuel flow. One more thing... pull the fuel line from the carburetor to make sure that there is a steady flow of fuel.

If all the above components are working correctly, then you might try this; fill the tank with premium fuel (NO Ethanol additives) and add 1/4 to 1/2 ounce of carburetor cleaner (B-12) and add Sta-bil (the recommended amount) to the fuel tank. The B-12 will clean the fuel path and the Sta-bil will stabilize the fuel. Start the bike as you normally would. It will take a bit to get the bike running so be patient. Once you have it running correctly, buy a can of Sea Foam (only if your fuel contains Ethanol additives) and add the recommended amount every other tank for about 4 tanks.

If you are still having issues after doing all the above, please reply with more information so that I may help you further.

Hope this helps. If you find this information useful, please vote on this post. Thank you.

Regards,

Oz

2001 Yamaha DT... | Answered on Jan 18, 2011


i had the same issue. it's gonna be a blockage in one of the vent tubes to the carb. check the line to the left of the carb that runs next to the gas tank. if thats fine then check the gas cap line. then if thats all good then check the line that runs below the carb. these are all vent tubes and allow the carb. to refill with fuel

2001 Yamaha DT... | Answered on Aug 07, 2010


check for blockages in your exhaust.

2001 Yamaha DT... | Answered on Jun 29, 2009


In the center of the under side of the motor/oil pan, you will see a diamond shaped plate held on by two screws/bolts and having a single wire coming out of it.

Yamaha DT 125 R... | Answered on Apr 04, 2019


Hi, Anonymous for this scenario you will need your service manual that has all fastener torque specs and a wiring diagram on the back pages, parts fiche, and owners manual if you can't find the best tool you ever bought for your Yamaha, despair not, for a mere zero $0 you can download another one.
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Yamaha DT 125 R... | Answered on Apr 06, 2018


Hi, Tim for this scenario you will need your service manual that has all fastener torque specs and a wiring diagram on the back pages, parts fiche, and owners manual if you can't find the best tool you ever bought for your Yamaha, despair not, for a mere zero $0 you can download another one.
For more information about your issue and valuable "FREE" downloads that you will need for viewing or printing please click on the blue links below. Good luck and have a wonderful day.
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Yamaha DT 125 R... | Answered on Mar 27, 2018


Hi, Gregorycnort for this scenario you will need your service/owners manual if you can't find the best tool you ever bought for your Yamaha, despair not, for a mere zero $0 you can download another one. For more information about your issue and valuable "FREE" downloads that you will need please click on the blue links below. Good luck and have a wonderful day.
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Yamaha DT 125 R... | Answered on Jun 12, 2017


Hi, Anonymous and the usual suspects are:
1. Fuel tank empty.
2. Fuel supply valve/petcock turned off.
3. Fouled spark plugs.
4. Engine flooded as a result of overuse of the enricher.
5. Vacuum hose to the fuel supply valve/petcock disconnected, broken, cracked, or pinched.
6. Fuel valve/petcock or filter clogged.
7. Fuel line to the carburetor or throttle body pinched or kinked.
8. Carburetor float stuck.
9. Fuel injectors clogged.
10. Severely discharged or damaged battery you need 12.5 volts or better and be able to pass a load test if necessary.
11. Check battery terminals for damage or corrosion, check the battery cables at "BOTH" ends for loose, corroded, or broken connectors, "INSIDE" and outside the cable harness, perform connector wiggle test and check cables with an ohmmeter if necessary.
12. Loose or corroded wire connection at the coil, battery or plug between ignition sensor and CDI box.
Spark plug cables in bad condition and shorting check for leakage in the dark, cable connections loose, or connected to the wrong cylinders.
13. Ignition timing incorrect due to a faulty MAP, CKP, O2, TPS, sensors.
14. Faulty neutral, clutch lever, or kickstand safety switch.
15. Faulty fuel pump or fuse or relay.
16. Faulty CDI box.
17. A stuck bent or burnt valve.
18. Tip over sensor needs a reset.
19. Check for engine trouble codes.
For more information about your issue and valuable "FREE" downloads that you will need please click on the links below. Good luck and have a nice day.
http://www.thumpertalk.com/topic/824422-dt175-will-not-start
https://yamahaclub.com/forums/topic/27070-79-dt175-mistery-wont-run
Yamaha DT100A 1974 Service Manual
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http://mybikemanuals.com/yamaha/yamaha-dt

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Yamaha DT 125 R... | Answered on Feb 01, 2017


Hi, Anonymous for this scenario you will need your service/owners manual if you can't find the first and best tool you ever bought for your Yamaha, despair not, for a mere zero $ you can download another one. For more information about your issue and valuable "FREE" downloads that you will need please click on the links below. Good luck and have a nice day.
https://yamahaclub.com/forums/topic/28097-yamaha-dt-125-sm-2007-starter-motor
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Yamaha DT 125 R... | Answered on Jan 16, 2017


Hi, Anonymous what you need is a wiring diagram that you can find in the back of your service/owners manual if you can not find the first and best tool you ever bought for your bike, despair not, I have found one for you that costs $15 dollars. For more information about your issue and valuable "FREE" downloads that you will need please click on the links below. Good luck and have a nice day.
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Yamaha DT 125 R... | Answered on Dec 19, 2016


Hi, Dennis it should be noted that in order to "PROPERLY" diagnosis any electric starter issue it is "IMPERATIVE" that you begin with a fully charged battery 12.5 volts or better and be able to pass a proper load test, and the usual suspects are:
1. Battery terminals have loose or corroded connections.
2. Battery cables faulty due corroded or broken internal wiring at the cable connector especially the "NEGATIVE" cable which needs to be checked at "BOTH" ends.
3. Battery voltage, must be 12.5 volts or better, voltage from the battery to the main circuit breaker to the ignition switch to the security/ignition fuse to the TSM/TSSM module to the engine stop/run switch to the starter button to the starter relay to the green wire that connects to the starter solenoid can not drop more than 1/2 volt of battery voltage.
4. With a voltmeter connected to the battery, the ignition switch in the on position, the kill switch in the run position, the starter button depressed, starter engagement should not bring voltage below 8-9 volts.
If a lower voltage is produced a proper battery load test should be performed with a load tester to validate battery integrity or battery replacement.
5. Faulty starter relay, check continuity.
6. Faulty starter solenoid, check contact plate and shoes for excessive electrical erosion/etching, refurbish as necessary or invert contact plate and use the virgin backside. Check contact shoes for being loose. Replace solenoid if the negative function is still a final outcome.
7. Faulty starter, bench test starter with a 12-volt battery if negative function check, decontaminate and undercut armature commutator segments as necessary, check segments with an ohmmeter probe each one and the segment next to it for shorts. Have the armature tested with a growler and field coils, and brush plate with an ohm-meter for opens, shorts or grounds. Replace brushes if less than .438" It is generally cheaper to overhaul/refurbish a starter motor than buy a new one.
For more information about your issue and valuable "FREE" downloads that you will need please click on the links below. Good luck and have a nice day.
https://yamahaclub.com/forums/topic/24325-dt125x-sm-solenoid-clicks-and-no-turns-over
http://www.motogelnar.cz/manual/YAMAHA/DT125X_RE-05-Service_Manual.pdf
OEM parts for Yamaha
http://www.dt125.cz/download/Owners_Manual-DT125R.pdf

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/gregg_c0ec1df182c7330e

Yamaha DT 125 R... | Answered on Oct 18, 2016

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