Question about Triumph Bonneville Motorcycles

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Coils are hot to the touch

Mild resporation on t120 bonneville. thought I had it when A. it wont start, and B the coils are hot to the touvh.... Appears to be wired correctly/per mannual....

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Hi and welcome to FixYa,

Offhand, am not familiar with a T120 Bonneville. However to my knowledge, there would only be 2 possible reasons why the ignition coil would heat up as you described:

  • the - terminal of the coil is wired to the ground; or
  • the CDI/igniter is shorted or in older designs, the contact point/condenser is shorted to the ground. On the contact point, it is also possible that the gap is erroneously set that it would appear to be shorted to the ground.
Good luck and Thank you for using FixYa. Happy Holidays.

Posted on Dec 21, 2008

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2007 bonnevelle america..runs for 15 minutes ignition cuts out wont start then 2 hours later starts.Changed coils and wires.Same problem .Where to look next?

Hi, Randy sounds like shades of Lucas Electrics the undisputed Prince of Darkness I would remove the tank again and meticulously scan all electrical connections and pay particular attention to signs of corrosion loose pins inside connectors etc. otherwise the usual suspects are:
1. Severely discharged or a damaged battery, should have 12.5 volts or better and be able to pass a load test if necessary.
2. Failed alternator/generator and or voltage regulator.
3. Loose or corroded battery terminals and or cables especially the "NEGATIVE" cable, look for loose, corroded, or broken connectors inside the cable harness at "BOTH" ends.
4. Failed main circuit breaker or ignition switch, check for loose connections and continuity.
5. Failed system and or ignition relay, check for continuity.
6. Failed ignition coil, ignition/electronic module.
7. Failed CKP, CPS, CMP, MAP, TPS, or BAS sensor, corroded, loose or broken wire connector pins/sockets.
8. Throttle cables and or idle speed improperly adjusted hot idle speed should be 950 RPM to 1000 RPM.
9. Air/fuel mixture screw improperly adjusted.
10. Accelerator pump damaged or not working.
11. Water or dirt in the fuel system, carburetor or filter.
12. Restricted, blocked or kinked fuel line.
13. Fuel tank empty.
14. The gas cap is not venting properly or fuel tank venting system blocked.
15. A failed fuel pump, pressure regulator and or fuel injectors.
16. Vacuum line from intake manifold to petcock broken, cracked, or not attached, carburetor vent line plugged.
17. Needle and seat stuck closed in the float bowl.
For more information about your issue and valuable "FREE" downloads that you need please click on the links below. Good luck and have a nice day.
Triumph Bonneville Ignition Control Unit CDI Limiter Failure
2005 bonneville t100 wont start no spark dies
Triumph Quit Ignoring Your Ignition Problems
Triumph America Handbook

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