Washed Bike -- Now Won't Start

[davidh]

So I washed my 2013 C650GT other day (nothing crazy, just a regular wash). When I finished I started it up, pulled into the garage, and went about my way. Next morning, I go to start and it won't turn over. I check the obvious things -- kill switch, side stand switch, brake lever switch -- all seem good.

I pulled the front-right off earlier today and checked both 30A fuses and all the little fuses. All in good shape. Battery voltage is 13.5+ V, connections are clean, all other electronics (lights, horn, windscreen, etc.) operate perfectly.

So here's what happens. Turn key, depress brake lever, hit starter, two seconds later I hear a single click. The click seems to be coming from the key-ignition module (below the handle bars). I pulled that cover off looking for anything obvious but no dice.

I've looked through the RSD manual looking for something else (another fuse, fusible link, something) that may have blown sometime after the wash but no luck so far. Any thoughts as to what I might be missing?

 

[Kim F]

Can't help too much but last time I washed the bike, it too was hard to start but it did eventually turn over. Makes me think it is sign from somewhere that it doesn't like a wash !

 

[davidh]

Can't help too much but last time I washed the bike, it too was hard to start but it did eventually turn over. Makes me think it is sign from somewhere that it doesn't like a wash !

Thanks! The dealer recommended I leave it in the sun for a few days so we'll see. I'm thinking my next step is to check the starter relay but it appears I have to remove ALOT of plastics to expose it. I have a 700-mile ride in a couple weeks (and, of course, the dealer can't get to it for three weeks) so i'm hoping I can at least eliminate some possible culprits.

 

[davidh]

OK, good progress! I checked all three relays next to the battery box and all three tested OK. I then started thinking maybe a connection problem. I sanded down the battery terminals and connections (the negative side was a bit corroded but nothing crazy). No change.

I then started verifying the ground connection between the battery and various places on the bike. No continuity anywhere -- weird, I say. I pulled off the left-side panels to get access to the engine ground connection and check between it and the negative battery cable. Pretty much nothing -- on the right track!

So I then connect a jumper cable between the negative post on the battery and a random bolt on the engine. Starts right up!

While it's running, I remove the cable and it stays running. I then remove the cable and it again starts up (several times in a row).

Then I notice something odd -- arcing at the ground connection on the engine. Something just a small spark but a few times it's as if I was doing some welding! Here's a link to the video.

So here's the question -- would a wonky negative cable (perhaps with a lot of resistance) manifest itself this way. My uneducated guess is that because of the resistance, it's drawing so much current that it's causing the arcing. And, if so, is the answer to replace the negative battery cable?

 

[davidh]

Me again. So I went ahead and installed a second connection between the battery/negative terminal and the engine. Used #6 conductor and lugs (conductor compressed into lug and solder-filled). No more arcing and I think the bike starts better now than ever.

For years I've noticed a little arcing but never paid attention to it -- the only time it was visible was with the center plastics off (which I typically only do when changing the belt). Maybe a design defect or something I've had going on for years! In any case, back in business and I can happily tell my dealer "no thanks" to the $225 "diagnostics" charge. I can only imagine what this would've cost me had they gotten their hands on it. Would probably want to replace the entire wiring harness since I couldn't find a single part number for the negative cable at MAX BMW.

Here's the pic of the finished product.

 

[Ceesie76]

Congrats, good work!

 

[Thom Davis]

Good detective work, Sherlock.

SO, bottom line, it didn't really have anything to do with washing the bike, right? Now I feel safe washing my bike again.

 

[jorgebri60]

Thanks for posting all your progress and subsequent success. Good Tech article. Question: did you try with just the new cable installed by completely taking the stock cable off? Just wondering if it us just a bad ground cable (obviously it is, you've proved that). If it works, why not just leave the new one in place and remove the old one altogether?

 

[davidh]

Thanks for posting all your progress and subsequent success. Good Tech article. Question: did you try with just the new cable installed by completely taking the stock cable off? Just wondering if it us just a bad ground cable (obviously it is, you've proved that). If it works, why not just leave the new one in place and remove the old one altogether?

Excellent question and no I didn't try it with just the new cable. My rationale for leaving the old one in place was:

1. Completely removing the original one would require a lot of work including removing all front end plastics, the seat, fuel tank, etc. to get good access to bolt attaching it to the engine.
2. I'm not certain what gauge the OEM one is. I used #6 conductor but it possible the original one is #4. I didn't install #4 since it's harder to fish through the frame.
3. I wasn't sure what might stop working if I removed the original cable. It's obviously good enough for all the low-current stuff but not for the starter, at least not consistently.

 

[davidh]

Good detective work, Sherlock.

SO, bottom line, it didn't really have anything to do with washing the bike, right? Now I feel safe washing my bike again.

Yeah, I can't figure that out either! Maybe just enough extra humidity to keep the cable from passing the necessary current. That arcing has been going on for years but everything worked and I didn't want to dig in to figure out what was going on.

 

[Skutorr]

The ground cable can corrode inside the crimped-on ends...

 

[davidh]

The ground cable can corrode inside the crimped-on ends...

Thank you -- that's exactly what it looked like. Never seen that happen nor sure why but the second cable seems to be working great.