K9 Electrical: Was the stock electrical good to go by 07 or still should be rewired?

Energy One

No H2O

Active Member
I *may* be closing in on a deal on an 07 K9 with the stock electrical wiring.
I'm reading that for 05-06 the stock wiring was problematic and should be replaced.
What about for 07? If it was/wasn't rock solid by then I'll have to take that into consideration price-wise.
And if it should be replaced, any recommendations on which wiring kit I should replace it with?
 

awg

Guru
I've been told that after 05 the EHC was better made and quality control was better also. Don't know about the wiring though.
 

woodbutcher

Mr. Old Fart member #145
Staff member
I've got an '07 and so far it is good to go. it has it's problems but not as bad as the earlier bikes. it's not really the wiring that is the problem, but there are some portions of it that might need addressed. for instance, originally, there is/was a plastic plug in the headlight which should be replaced with a ceramic plug and that should be taken all the way back to the undersized JST fitting under the tank. that fitting was put there for ease of assembly, just cut it out solder it and use shrink wrap on the joint. from all that I have read, Curtis has the replacement EHC that is the easiest and most reliable replacement produced by member "Axel". just happens to be the least expensive and best warrantied unit also. and the right hand control board does cause problems, but that is typical with most other '05 and up. all in all, I am happy with my '07. just takes a little while to finesse the kinks out of them, no matter what year you choose.
 

Brandon Downey

Active Member
I also have an 07 Mastiff with stock wiring and have had zero problems in just over a year of ownership. Prior to buying I spoke with a Big Dog mechanic that used to work at the dealership when they were still in business and he said by 2007 the wiring/electrical issues were pretty well sorted out. So far he has been 100% correct.
 

MossBerg590

Active Member
If you get it and want to replace the ehc as a precaution and currently have no problems, then I would go with Axles unit from Curtis like mentioned above. Just unplug and plug new one basically. Then keep your old ehc as a back up or sell it.
 
There is nothing wrong with the BD electrical system in general. A good portion of the electrical failures are directly linked to the crap charging system, namely the voltage regulator, that BD was putting in the bikes. Get into a good CompUFire charging system and you won't have majority of the issues they're known for. A rewire is never necessary.
 

SKOGDOG

One of the old ones.
The idea that every EHC in an older BDM needs replaced is nonsense. They do have an unacceptable failure rate, but no one will ever know what that really is bcs so many have been changed unnecessarily. Ask Mr. Wright about how many ech’s are replaced when the fault lies elsewhere.
Blacktopper has an ‘07 K9 with 85,000 miles on it and had never had a single electrical issue—ever. My 08 had 75,000 with the original ECH still going strong
If the bike shows a prior and current clean bill of health for electrics, buy it and ride it.
 
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