Exactly what I posted back in 2007 .....teazer wrote:A bigger issue with a ZD is that it basically dissipates electrical energy as heat and these bikes don't exactly have surplus power to throw away.
Say What? Too much charging?
Last edited by e3steve on Wed Jun 23, 2010 2:46 am, edited 1 time in total.
Brent, where are you measuring the 17V? At the battery terminals? Rectifier? And on the DC side or into the rec on the AC side (which would be pretty much normal)? Check the voltage at the headlight (with the light on); it needs to be on to dissipate the load, thus reducing the voltage to its design level. I've posted many words on my improvements and findings during experimental (and now 'stock' on my CB) stages; made some misjudged assumptions (see later in this post) in the early period, too!
Well, Brent, that 17V seems high for a 'terminal voltage', so no wonder you're bike is popping lamps. I ran mine to 6000rpm or so yesterday, with my DMM connected again; terminal voltage is circa 13.4, increasing to 14.5 with the lighting switch ON but no headlight selected (I have an LED taillight and no front parking light [different headlight ass'y]). Also I've 'saved' attenuation in using a Schottky-diode (less loss than a silicone-diode) rec. Aside from the LED taillight I'm using a Philips Motovision 35/35 H4 headlight bulb. I'm in the same profession, Gunner. I agree with your obs that, for a show bike, the RetroBikes' device would be a perfect choice. I used the space previously occupied by the bloody great finned thing to accommodate my horn & flasher relays, as my 25A rec & heatsink combo is half the size of the original; and I'm not too concerned with originality under the seat. Incidentally....
Well, Brent, that 17V seems high for a 'terminal voltage', so no wonder you're bike is popping lamps. Have you checked calibration of your DMM by referencing its DC measurement on a known voltage source (another range of batteries: say a 1.5V, a 9V and a 12V, your car, por ejemplo)? A car battery should settle, quiescent (off charge/off load), at around 12.8V. I ran mine to 6000rpm or so yesterday, with my DMM connected again; terminal voltage is circa 13.4, increasing to 14.5 with the lighting switch ON but no headlight selected (I have an LED taillight and no front parking light [different headlight ass'y]). Also I've 'saved' attenuation in using a Schottky-diode (less loss than a silicone-diode) rec. Aside from the LED taillight I'm using a Philips Motovision 35/35 H4 headlight bulb. I'm in the same profession, Gunner. I agree with your obs that, for a show bike, the RetroBikes' device would be a perfect choice. I used the space previously occupied by the bloody great finned thing to accommodate my horn & flasher relays, as my 25A rec & heatsink combo is half the size of the original; and I'm not too concerned with originality under the seat. Incidentally.... I took some voltage measurements on my bike a couple of days ago:
13.05 v @ 2000 rpm 13.8 v @ 3000 14.05 v @ 4000 14.6 v @ 5000 I used the electric starter, briefly, allowed a few minutes of warm-up, then measured at the battery terminals with the headlight OFF and no load other than the ignition circuit and neutral lamp. I have a silicon bridge rectifier and a pretty new battery. The bike has LED winkers and LED brake/tail lamp. I might have to hook up my oscilloscope to confirm the voltages and look at the waveform. Wilf
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