21’ low rider s that gets an intermittent starting issue on a cold start. I’ll try and start the bike and it won’t crank over on the first try, I start it again and it starts up rough and will give a p1608h (intermittent loss of power) cel code. This happened a month ago and I tightened all battery connections and hasn’t happened again until this morning, the bike was not on a battery tender and wasn’t started for about 5 days. Last time it happened the bike went into limp mode but eventually got it started and got it home. I know these Milwaukee 8 motors are electrically sensitive and any drop in power can generate a code. Anyone have this issue? I’m thinking my battery might be going bad. The clock also resets every time this happens.

 

I have a 2007 Fat Boy and a 2017 Heritage Classic. Both were bought used. The 2017 still had its original battery this spring, making it 5+ years old. The 2007 coincidentally had a battery dated 5 years ago. Both bikes started having an issue this year if they were left off of the maintainer for 3 or 4 days. I'd hit the starter, it would crank one revolution, lock, then spin-up and fire. The 2007 failed me on the road one time and I had to jump it. Both bikes would reset the clock when this happened. I did the usual connection checks at the battery and ground wires and both bikes were fine. I charged the 2017, pulled it, and had it load tested. It passed on the first load, failed on the second. I replaced the 2017 battery and the problem was solved. I then replaced the battery in the 2007. In the future I will consider it an early warning that when the clock starts resetting, it's time to think about a new battery. No one should have to buy 2 batteries in one season, but both being over 5 years old - I can't complain.

 

If you have a multi-meter, you can do a load test on your battery before removing it...

Make sure it's been off any battery maintainer for a couple hours. Then measure the standing voltage between the neg and pos battery posts. You should have 12.6+ voltage for a fully charged battery.

If you can't one-hand it, use clips, but now measure the battery voltage as you start the engine. With the key on, the voltage will drop a little.

When it first cranks over, it will drop quickly, and then partially recover. If it drops to below 9.5v during the starting process, your battery is getting tired, and you should consider replacement... There are videos on youtube showing how to do this...

It's always easier to replace a battery in your garage than it is to replace a battery on the road...

 

thanks for the reply, your situation sounds familiar. Did your bike throw any codes with the weak start up? I started mine this morning without any issue and no codes. I bought the bike used and came with mini apes on it so handlebar work was done which concerned me at first because the first incident a month ago I got like 6-7 codes relating to the throttle sensor and such but after researching it said if battery voltage is low it will throw of codes due to safety with the fly by throttle and regulating proper voltage for proper air and fuel mixture which made sense. I’ll just keep it on the tender and see if it still triggers a CEL.

 

Thank you, good advice, I will try it. I do have a couple fluke meters, I’m sure one has a low/max button to record the lowest voltage measured…might just be for amps though.

 

If you just watch the meter, you will see it dip with your eyes, it's not that fast...

Keep us posted...

 

Neither of my bikes threw any codes. Both are EFI. One is TBW, the other has throttle cables.