Voltage Drop
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Road Master
Joined: May 2007
Posts: 1,034
Likes: 3
From: Open Road, USA
Voltage Drop
I noticed some time back that when I applied the front brake, the voltage gauge would drop to 12-12.5 volts(estimate)and would return to 14+when I released the lever. Didn't really worry to much about it, but not it does it when I apply the back brake. This only happens when sitting at a light,etc. If I rev the motor it will increase back to normal as long as the rpm's are around 1100 or so.
I see three possible causes: 1. The turnsignal/brakelight module has an internal short. 2. The brakelight has a short. 3. Brake light switches going bad.
Anyone had this problem and found the culprit that causes it. It's just one of those things that aggravate me, and I really don't want to pay my indy to track it down...
Joe
I see three possible causes: 1. The turnsignal/brakelight module has an internal short. 2. The brakelight has a short. 3. Brake light switches going bad.
Anyone had this problem and found the culprit that causes it. It's just one of those things that aggravate me, and I really don't want to pay my indy to track it down...
Joe
Tourer
Joined: Aug 2008
Posts: 330
Likes: 1
From: Arkansas
Usually I'd think the battery was beginning to weaken or maybe it hasn't completly charged. I think you said you put a new battery on it in another thread. Brake lights putting a drain on the battery and when you rev it up the alternator applies extra amperage. The alternator doesn't actually start charging till 2000 rpms.
Seasoned HDF Member
Joined: Mar 2010
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From: Honah Lee
I think what Blue says. Charge your battery good, remove it and carry it to autozone and have them do a free reserve amp load test. Bet its weak. Usually when it gets this way you will get an occasionly grunt before it starts spinning from a cold start up. My FI idles at 1000-1100 so I may not notice it however. I know it take 2000 rpm to get full charging volts of 14.8 or so. I get the chance I will clip my meter to the charger wires and pull the idle down with the clutch and notice volts. What's your idle speed
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Road Master
Joined: May 2007
Posts: 1,034
Likes: 3
From: Open Road, USA
My idle speed is 900-1000 rpm...I just replaced the battery, but it still does it. Am going to experiment and unhook the brake light/turnsignal module..It didn't start doing this until this summer when it was so damn hot...Replaced the stator last summer..
Joe
Joe
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6th Gear
Joined: Apr 2009
Posts: 11
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From: Texas
Hey Joe, I've been having the same problem as you every since I got my old glide a few years ago. There were work receipts for what had been done by previous owner, and a stator and regulator had just been replaced also. I put a new Odyssey battery in last year at the recommendation of a riding friend, so like you, I know it's not the battery. I went over all my grounds as a possible reason, but they all tested good with an ohm meter.
Although I do have a suspicion about the stator/reg work, as the shop that did it proved to be idiots in other areas of their reported repairs. That's a whole other story, but I wouldn't be surprised if they pulled a fast one somehow. I am tempted to get a 3 phase stator setup, but if it's something the monkeys did wrong, I may be satisfied if I can find the problem.
Although I do have a suspicion about the stator/reg work, as the shop that did it proved to be idiots in other areas of their reported repairs. That's a whole other story, but I wouldn't be surprised if they pulled a fast one somehow. I am tempted to get a 3 phase stator setup, but if it's something the monkeys did wrong, I may be satisfied if I can find the problem.
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Seasoned HDF Member
Joined: Mar 2010
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From: Honah Lee
Just my opinion and maybe be reading what you say wrong but my bike is same as yours. I also have a new ventilation hole in back of my shed from a Harley front wheel. (just kidding)
Just read you idle speed after getting back from a 5 mile run. Went out and checked mine at the battery charger terminals. My battery is stock, old but checked at beginning of summer for reserve amps at AutoZone and it was OK.
12.55V key off
12.01V key on bright lights not running.
I learned something. Thanks
11.7V above and signal light ( a wow 11.1V with flashers going)
8.9V starting (little border line but my battery is 4 years old)
13.67V at 1000rpm
14.2V at 2000 rpm
(actually stayed at 14.2V or so when I dropped it back to 1000rpm.
12.4V 850rpm using clutch to drag motor down while holding front brake. (note that is battery voltage and shows little charge at this low speed.)
Thanks, learned something.
Just read you idle speed after getting back from a 5 mile run. Went out and checked mine at the battery charger terminals. My battery is stock, old but checked at beginning of summer for reserve amps at AutoZone and it was OK.
12.55V key off
12.01V key on bright lights not running.
I learned something. Thanks
11.7V above and signal light ( a wow 11.1V with flashers going)
8.9V starting (little border line but my battery is 4 years old)
13.67V at 1000rpm
14.2V at 2000 rpm
(actually stayed at 14.2V or so when I dropped it back to 1000rpm.
12.4V 850rpm using clutch to drag motor down while holding front brake. (note that is battery voltage and shows little charge at this low speed.)
Thanks, learned something.
Last edited by Jackie Paper; Sep 10, 2011 at 01:37 PM.
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