New 80/100 headlight?

Discussion in 'Electrical' started by Bodeen, Feb 21, 2010.

  1. Bodeen

    Bodeen Well-Known Member Staff Member Moderator Contributor

    4,317
    73
    130
    My wife and I were on are way home last night from a 350 mile ride. I noticed at the traffic lights that my headlight goes pretty dim at idle. I do have the new 80/100 headlight that is suggested in the self help section.
    I haven't noticed the starter dragging at start up or anything. It brightens right up as soon as I just run up the rpm a bit. 2003 FLHR no clue as to the batteries age. Is this something I should be concerned with?
    Maybe my idle rpm is too low, which brings up my next question. How do I check idle rpm on a bike with no tach installed?

    thanks in advance,

    Bodeen
     
  2. Mattman4403

    Mattman4403 Junior Member

    602
    26
    1
    You will be pulling more juice at idle than with the lower wattage bulb. Not sure if your bike is injected or not. On the FI bikes the idle is set around 1000 RPM. If you are a lot below that, you may want to bump it up a bit.
     
  3. Davidw2415

    Davidw2415 Senior Member

    1,456
    46
    0
    Well if this issue was in my truck or my wife's suv I would suspect the battery and/or alternator but I'm not sure it would be the same diagnoses for a bike. I'm sure one of our experts will be along soon.
     
  4. glider

    glider Veteran Member

    25,464
    108
    44
    Two things it could be is first a weak battery, have it load tested after a full charge and second as mentioned the idle speed. If you don't have a tach on the bike, you would have to rely on the dealer to check/set it for you. It should be in the 950-1050 range for everything to work right. My money is on a weak battery being a 2003.
     
  5. Bodeen

    Bodeen Well-Known Member Staff Member Moderator Contributor

    4,317
    73
    130
    Update: It was indeed the battery. Pulled the old battery and the date punches were never torn out so I didnt have a clue how old it was. I bought the bike in July with the battery in it. The starter has seemed a little slower than normal lately. I just bought a new one for peace of mind. Light stays bright at idle now, no problem.
    Sheriff slowed in traffic the other evening while my wife and I were out for a ride. We pulled to a stop light and he asked why I dont turn my high beams off. I told him because they weren't on! He said that light is way to bright! I asked him if he was going to give me a ticket he said no and we went on our way. That 80/100 is in fact bright! I did check the adjustment and it was really close to what the book says to have. He was just bored I guess.

    Thanks again Glider, good to see you around here again.

    Bodeen
     
  6. NEWHD74FAN

    NEWHD74FAN Experienced Member Retired Moderators

    8,176
    98
    16
    Bodeen, glad you got it sorted, when I first read your post, the minute you said that the headlight brightens up when you rev the motor a bit, I knew you had a bad battery as the age of your bike is about right...even mine which was well cared for needed replacement. Using the headlight as a rough guide for battery condition is how I troubleshoot, if an abnormal condition occurs when starting.

    I also use the 80/100W bulb and it is indeed quite bright (intended for Off Road use) but just make sure you check the aim of the bulb, level bike shining on the a flat wall and level 25 feet away (owners manual shows beam aiming check method). Enjoy the ride!
     
    Last edited: Feb 27, 2010
  7. glider

    glider Veteran Member

    25,464
    108
    44
    Glad you like the bulb. I run them in every bike I had.

    Thanks