I have a 04 RK Classic and have a problem that I cannot figure out. My bike misfires while riding and sputters. It is at random times and it is hard to diagnose. Sometimes it happens after a long ride and other times it happens as soon as I start riding. I have changed the plugs and wires, cleaned the throttle body and cleaned all the grounds. We tried to test the coil but really couldn't get a reading so I am not sure. I think the next step is to change the coil. Can anyone recommend a high performance coil? It seems Harley doesn't make the screamin eagle coil anymore.

If anyone has any other recommendations I would appreciate it.

Thanks in advance for your help

 

not sure on the high performance coil, but definitely does sound like symptoms of a coil going bad. Good luck, hope you get it working!

 

be aware that cranking the motor with the plugs/wires etc not connected can blow your coil.

so you can start tying to find one problem, cause another ( blowing the coil), then find the initial problem still exists.


stock coils are good- the idea of a "performance coil" had more to do with points ignition systems- now that we have electronic ignitions just about any coil out-performs, outlasts the old "performance coil".

Crane cams makes good coils, I had them on my '95 ( when converted to dual fire), so you could check there.

you've been through you grounds, check as many connections as you can. also check you battery cables, I have seen the insulation wear partly through and the + cable short out on bumps.

you have already ruled out a hot/cold sensor situation, can you influence the problem by shaking or bouncing the bike

mike

 

I was curious what this problem was, my 04 Heritage is doing the same thing. Let me know if you can. Thanks, Joe.

 

One suspect would be the TPS (throttle position sensor). Mine had random misfire issues as well as high-idle for a year, getting worse the last month or so. I changed the IAC, fuel-pressure regulator and all internal hoses, plug wires, and finally the TPS. It's been trouble-free now for a year. Voila!

Is your ECM throwing any codes?