Just purchased a 2003 custom soft tail chopper that turns over just fine but no fire at plugs. the bike wasnt running the day i purchased it but did the day before. The guy i got it from had drug the bottom of the bike on something and in process some wiring was caught,didnt cut them into but did cause them to short out. Blew head lites out,possibly the ECM,i removed it,an aftermarket Dyna power programer that has adjustments for timing and rev limiter,and put it on my 2003 Dyna which runs until i put the ECM from the bike in question on it so i assume the ECM is bad. next i took the ECM from the running Dyna,put it on the non running bike,same thing,no fire but turns over.I havent found any fuses or relays any where on the bike where my Dyna has several of both. The bike in question is a complete hand built one off custom soft tail chopper built by Donnie Smith custom cycles in Blaine MN. therefore has a custom wiring harness thats nothing like the harness on my Dyna.sorry for such long post. I'm at a loss as what to try next to get it running. the wires which were damaged come from left front of engine,2 wires then large connector then 2 wires run to right side of bike then under bike under oil pan then back to left side and appear to go into back side of the primary,i think this is what its called,contains a large belt. what all could be damaged from these 2 wires getting damaged? there are not a lot of electronics on the bike,there is a map sensor,coils and ECM and not much more that i can tell so far but then im no bike mechanic but im not afraid to tackle my own repairs on about anything with a motor. I hope someone here can point me in right direction im bout crazy messing with this bike but refuse to give up.thank you for any support any of you might offer.

 

3 things a motor needs to fire - Air, Spark, Fuel
* Did you confirm Air and fuel. Was spark confirmed not to be there..
* Theres a difference between failure and damage. Failure, find the part and replace it. Damage which is what this sounds like - there can be multiple points of fixing. It sounds like lots of patience and a good multi-meter. Check point 1 first. fix and repeat.

 

Since there is no wiring diagram you will have to make one. Good for you that there aren't that many electrical features on this bike. I would start at the ECM and work your way forward/back.

Once you identify all wiring it will be easy to identify the cables that are hot and the ground wires.

I caution you from putting a good ECM on damaged wiring. If the wiring damaged the old ECM which you say it did since the bike was running, then the same wires WILL damage the new (good) ECM if the wiring has not been repaired.

 

you said there are only TWO wires going into the Primary not three? Sounds like you might be running a magneto, and if those two wires got shorted when it was in operation, it could have burnt the mag internally. the good news is you can tell with a multimeter.

 

That's a long post so I didn't read it all, Do you have an alarm? Will you get a spark with a battery booster? I know I've had similar issues so I'm now looking for a battery with 400 cca power...

 

The wiring that goes between the rectifier in the voltage regulator was damaged it wasn't cutting too but apparently it was damaged enough to short out I didn't see the wires when they were damaged as the shipping company had already taped them up.with a short in these wires because that mission module to get damaged in the crank position sensor and map sensor, even both headlights were blown. How is this possible without damaging the battery minder standing is the voltage regulator just regulates the voltage to the battery I am so confused on this I'm about to pull my hair out .
I ordered a new crank position sensor and map sensor I pick them up tomorrow I'm going to try replacing both of these and put a good ignition module from my other bike on it to see what happens at already tried to get ignition module on there with no results the bike still just turned over but no fire I've tested the coils and it seems they're fine.
The company that built the spike mounted the voltage regulator inside the backside of the primary and to my understanding this would not be a good idea as the voltage regulator despite so much heat along with the heat from the primary so my solution to this is to just bypass that voltage regulator and I had a new one and put it in the stock location As I am unable to get the cover off the primary to check out the voltage regulator because of the kind of Loctite they used I'm afraid I'm going to end up stripping the bolts out trying to get the cover off . Therefore my solution is to bypass this and just leave it where it's at what do you all think about this. I spent $210 on a crank position sensor and map sensor and I'm sure I'm going to have to replace the ignition module which is probably I'm guessing around $300 more as well as the voltage regulator which I'm not sure the cost on it probably $100 which is easily gonna put me on the eight or $900 range. I'm just assuming that the voltage regulator is probably out being that the wiring was shorted out.

 

That's a decent plan for the electrical, although have you verified the stator is not internally shorted already? The external short, could have caused an internal one as well, and I would hate to see you possibly damage new electronics during troubleshooting. As far as the locktite on the primary bolts, it is time consuming but hit them one at a time with a heat gun, at least the short ones, and an impact driver should pull them out then. The long ones might not come out as well like that, but worst case you can drill the heads off, and get them out with heat and vice grips after the primaries are off.

 

Can anyone tell me what all could possibly be damaged when the wiring from the rectifier to the voltage regulator was damaged it wasn't cutting too but I'm sure that it probably got shorted out . I tried replacing the ignition module that didn't give me any results the engine still turns over but there's no fire to the coils,the coils are good,tested those,the fire, The engine turns over fine I just don't get any spark at the plugs I took a working ignition module off of a bike with the same engine and I got the same results no spark, also on the wiring was damaged it even blew the headlights out . I guess I'm going to start with the crank position sensor in the mess airflow sensor and I plan on bypass in the voltage regulator that's mounted in the primary and adding one in the stock location as I'm not able to get the primary cover off to check the voltage regulator of this bike was custom-built and they installed the voltage regulator inside the primary to keep a clean look on the bike which seems to me would cause the regulator to overheat anyway.if the rectifier got damaged or the voltage regulator got damaged would either of those cause I know spark issue at the coil even if the battery was hot the battery wasn't damaged