'08 Mastiff intermittant break up

[chopperchris]

Hey all, I am attempting to help a friend with his '08 Mastiff, 117 S&S. I have serviced the bike and it starts and runs mint other than this one issue. The bike will intermittantly break up when running above 4500 rpm's. In order to get the bike to do this I am riding in second gear and bring it up around 5k rpm's (it breaks up) and then shift into 3rd, open that gear up til around 5k and it will break up again. It won't do it every single time. From what I have researched, I think this stock ECH is crappy and there is an upgrade of some sort. Thanks for the help.

 

[francoblay1]

Don´t blame the EHC..... right HERE :up:

 

[Iman]

Do an intro chris - and there will be plenty of help coming your way - Welcome from Coastal SC

 

[KaptinAmerika]

The EHC has nothing to do with the Ignition
The bike likely has an electrical leak in the Ignition wire harness being caused by the high vibration
The only way to find that is troubleshooting the electrical

 

[chopperchris]

The EHC has nothing to do with the Ignition
The bike likely has an electrical leak in the Ignition wire harness being caused by the high vibration
The only way to find that is troubleshooting the electrical

Thanks for the help, I will trace all the wires now to make sure there are no breaks.

 

[BWG56]

Try another set of plug wires, spark might be coming through insulation at high RPM's.

 

[Brew]

Sounds like you might be spiking and hitting the lower limit of the rev limiter. Be sure you're not spiking past 5K and aproaching 6K. My 08 Mastif would do the same until I put this new thunderheart programable ignition on, now it screams. Just saying, keep your eye on that RPM closely and be sure...

 

[BigDogBro1]

Make sure the voltage regulator is bolted tight to the frame it needs a GOOD ground. It caused a 4000 RPM cutout on Bigdogbro2 EFI bike.