Well after a short ride, went to visit a friend who wasn't home, turned right around to leave and the bike would not start. It is an '04 FXDLI. I tried pushing it but couldn't get enough speed up. Luckily a neighbor had a charger andI was able to jump it from that. I am on my second battery which is I think just about a year old. I have been riding fairly steady the past several weeks so I was a bit surprised. I did have a similar problem a couple months ago, got up into the mountains, stopped for a short break and it wouldn't start. But that was an easy fix I just coasted downhill a bit and dumped the clutch while in gear and she fired right up. At the time I kinda blew it off as an anomoly. But now I know I definitely have some issues. The battery is currently on a charger, trickle at 2 amps. Is there a way to check this battery before I just laydown the cash for a new one. Seems a year is not very long, considering I got almost 3 out of the original. BTW I just ordered a HD battery tender from Chicago Harley but I'm sure it won't restore this battey if it is already gone. I sure will use it on future ones though. Thanks for any input.

 

I also wonder why the MOCO doesn't put a cutout on the headlamp when the starter is engaged? This seems to me to be a big drain on the battery during startup.
Does anyone know of an aftermarket kit to do this?

 

the amps your starter pulls in relation to the headlight makes the H/L look like an LED, lol

as for your batt, have you checked your charging sys?? when the batt is fully charged, hook a multimeter to it in the bike and rev up the bike, you should hit at least 14.5 VDC, if you don't your charging sys may be weakining or going out on you.

also, when you start the bike, the batt VDC should not drop much below 11.0, as the ign needs 10 volts to fire. if it does, your batt is toast.

 

Battery seemed to hold a trickle charge. Twenty four hours later it is holding at 12.8-12.9 volts. I re-installed it andchecked it with the engine reving and at idle it is the same 14.25-14.3 volts. Couldn't get to 14.5 and that was reving at 3000.
So what do I need to look for in the charging system.

I think part of the problem is simply keeping a good tight connection at the terminals. The damn screws just don't stay tight. I even put blue locktite on them last time and still you could move the contact with only moderate effort.
Oh. also, I hooked up the pigtail so when I get the tender I will be good to go, I'll keep it on trickle all the time. The other nice thing about the pigtail is I can now check voltage without removing the seat.

 

try to make sure the weight of the cables isn't pulling them loose. it's clockwise to tighten so the weight of the cables should be to the right of the fasteners to hold them tight.

 

Huff huff,
That is a good point. The cables are barely long enough to reach the terminals, I actually have to set the battery in the box and tilt it out slightly to attach the leads. You'de a thunk they could have made the cables an inch or two longer, as it would make installation and removal that much easier. I will definitely try and rotate the leads as you suggest.

Any input on the charging system? Does less than 14.5 volts on the meter at 3,000 RPM mean there is a problem in the charging system?

Thanks,

 

I don't recall the exact specs but I think 13.5-14.5A is the acceptable range. Heat will take it down fast, the regulator heats up and creates more resistance, hence the cooling fins. Your readings are well in the acceptable range. 14.5 is the maximum possible with perfect conditions all around.

 

at the risk of repeating myself, have a read of this which I wrote for some friends with similar issues.

All corrections gratefully received, I am no expert.

http://www.harley-davidson-hangout.com/forum/hdrcgb-tech-tips/42341-troubleshooting-your-charging-system.html

BTW, if you rev the bike but can't get it past 14.5 volts, that is a GOOD THING. the regulator is regulating the amount of voltage to the battery. But on the down side, it may be, for instance, leaking battery voltage to earth.

Do some tests. The first one I would do is the 'poor man's load test'...... battery may be showing 12.8 volts all week, but turn ignition ON and what does it show? if it drops to 12 volts or less, the battery is toast. It cannot hold a load. Then you gotta find out WHY it got damaged.....

I have been down the route of replacing batterys and nothing else. It's like putting a Band-Aid on a broken leg! Live and learn!







(hey DeJavu, you are not kidding with that sign-off message!!!!!!!)

 

 

In addition to Kiwidave2's great tips, If your headlight blows out the first thing you should check is the regulator. Bulbs can only take 16v before the fry. Blew 2 in succession before I found that out.