Dong Fang DF 250 RTB Bobber Information

**barnone** · 05-19-2011, 11:07 AM

You have 15 volts at the battery when the engine rpm is raised but only 10 volts at the headlight? Sounds like to me that the charging system is working properly.

That is strange and needs some more though before parts are swapped out.

The owner's manual has a wiring diagram that needs to be studied.

What is causing the voltage drop of 5 volts?

**reporon** · 05-19-2011, 11:22 AM

Barnone, I thought possibly a bad ground. so I ran a jumper to a good ground and found no difference. I have been looking at the wiring diagram. I am stumped.

**barnone** · 05-19-2011, 11:25 AM

Where did you measure the voltage at the headlight? Was the voltage the same on low and high beam? Try a different bulb?

**The Other One** · 05-19-2011, 11:27 AM

I would see what happens when you run wires from the battery directly to the light. If you still have an issue then the problem is the light and you don't have to go through all the wiring. (I doubt thats it though).

Different bulb is a good idea to try too. Try all the easiest stuff first. If you can just use a more powerful bulb, then you may not even need to worry about it unless you later on find out that there is a short draining your battery. Even then, you can install one of those battery cut off switches so the battery doesn't drain when the bike sits for a few days. I put one of those on my plow truck because one of the previous owners screwed up the wiring so much that it would be a nightmare to find what is causing a slow drain on the battery.

**reporon** · 05-19-2011, 11:30 AM

I took it right at the bulb. did not check the diff. from the hi to low beam. I could try a diff. bulb. I wonder if I could pull power directly from the battery (with an inline fuse) just to check if this makes a diff.

**barnone** · 05-19-2011, 11:59 AM

Originally Posted by reporon

anyone run the df at night? my headlight is real dim. when I apply the brake it brightens up a little bit. at idle it seems ok but when I rev it up some it starts to dim.thanks

reporon,
The above is still true? "when I rev it up some it starts to dim"
Good problem. So when the voltage increases (15V) then the headlight dims? In order for the headlight to dim then the resistance somewhere in the circuit has to increase. Have you observed the tail light dimming?

**reporon** · 05-19-2011, 12:49 PM

yes, when I bring up the rpm's the headlight still dims. I have not noticed if the taillight dims. I will check that. I did notice that when I apply the brake the headlight brightens up a bit.