Hi all!
My friend asked for my help with his radio install on road king. Source is iphone, sony head unit, the goes to the RF PBR300x4 driving a pair of kickers 6x9 on saddlebag lid. The installer did a half assed job by using 10 awg power cable and maze like wiring. Now the problem is head unit and amp cutting out when the engine rev to 3500 rpm and above. I have measured batt voltage at 3500 rpm and it was 14.2V so I didn't think it was over voltage or anything, everything also cut out when the volume is cranked beyond 60% even on idle..

Apart from rewiring everything with proper wire, what should I look for to solve the problem? Don't wanna rewire everything and ended up with same problem.

Thanks in advance folks!!

 

What speaker model specifically, and why did the installer use a 4 channel amp while only pushing one pair of speakers?

10 guage wire is enough to power that amp so that isn't the problem. If he's using 2 ohm speakers with a pbr300x4, that could be it.

 

go with what Pioneer74 said on the speakers first before you do anything. That amp is ONLY capable of running a 4 ohm load at each of the 4 channels. Aside from that, here is what I would look at.

the higher you crank that volume, the more current has to flow from the ground to the amp back to the battery. So you have power wires to look at as well.

1. if the installed did such a crappy job on the wiring then I would first take a look at the main power wire and make sure the fuse holder and terminals used are good, appropriate, and not jacked up. Bad connections in electrical wiring make for fun troubleshooting.
2. take a good hard look at the ground location and the ground wire itself. It MUST be the size of the power wire, in your case 10ga.

As I stated above and you might be scratching your head about; Despite what most people think, power does not flow from + to -, but just the opposite.

 

The owner is preparing the extra channels for lower fairing speaker when he got the money for lower fairing and speakers. So yes currently there are 2 channels unused. I read somewhere that RF PBR300x4 also does not do well with channels being unused, can this be the problem?

It is Kuryakin injection molded saddlebag lids with 6x9 Kicker speaker with separated mounted tweeter. Not sure about the ohm, website doesn't say anything about ohm and I didn't check the specs from the actual speaker yesterday, I will look into it. However, if the problem is with speaker resistance then only the amp will cut out right? Not the entire system?

 

I cut the wayyy too long 10GA wire and re terminal both power and ground wire going directly to battery, off course with ground wire being equal size, still ended up with same problem, so it is not problem with wire to the amp. I haven't tackle the other wiring because I was planning to just pull apart everything and rewire it properly with proper wire. I know the importance of proper ground, but this guy's previous installation is a serious spaghetty network, the head unit power is being supplied from running light, cooling fan for the amp and HU tapping power from HU and Amp, head unit's ground wire so damn long I don't know where it ends, a complete mess I would say...but like I said, this is my friend's bike who don't know a thing about technical stuff, so I will be doing everything for him for free, so I want to make sure I do not waste my effort by chasing my own tail.

Thanks a lot!

 

this is probably the smartest thing to do. I hate cleaning up someone else's wiring mess and it usually winds up taking a lot less time taking it all apart and redoing it.

 

LOL! I guess it's inevitable...I better text him my favorite beer...