Battery drain while bike is on.

[Normk]

Just a general observation:

I have had the most relable results in testing diodes by using a test light and 12 volt power source rather than a meter diode tester. Not criticising others' solutions but try doing a few hundred high capacity diodes and let me know if you agree.

HIH

Norm

[Smellii]

I'm all about it if it's cheaper and more reliable.

[tom203]

I'm all about it if it's cheaper and more reliable.

Well then, I hope your replacement had the Shindengen label on it, cuz there's no cheaper/reliable R/R.

[tom203]

Just a general observation:

I have had the most relable results in testing diodes by using a test light and 12 volt power source rather than a meter diode tester. Not criticising others' solutions but try doing a few hundred high capacity diodes and let me know if you agree.

HIH

Norm

I feel the current crop of bargain digital multimeters is ideal for testing the small size diodes we have. I've tested my cheapos with the Schotsky (spelling ?) diodes which have a much lower forward voltage drop than conventional diodes and been surprised- see for yourself!

[Normk]

Unless you are showing over 14 volts, the battery will not charge at any useful rate. Rather than some drain which is only present when engine is operating, it may be better to consider that the alternator output is not exceeding the load.

Does voltage rise with headlight fuse removed or headlight switch off?

Norm

[Normk]

I'm not sure that I understand your point Tom203, could you re-phrase?

Are you aware of the use of Schottky diodes in alternator rectification circuits? It was my understanding that they are a low power diode with high reverse current leakage so understood that they aren't used in rectifier circuits like for our bikes. The trick thing seems to be a controlled MOSFET although there may be an advantage to use of a Schottky diode for controlling the MOSFET but this is going out of my depth.

If you are stating that even the low cost meters are reliable for testing Schottky diodes then I accept the point as have no experience in that regards.

My point was with reference to power rectification for vehicle alternator applications which I think are exclusively silicone diodes if a straight diode system is used. This is the case in all the automotive alternators and controlled stator field circuit motorcycle alternators which I have encountered. Any separate bike regulators seem also to be silicone diodes, IME.

There is nothing so reliable as the testing by actual operation so placing a reasonable load through the diode has always shown to be reliable although meters are not universally so.

Again, not offering to dispute others' techniques.

If testing a stator, rotor or motor/generator field winding for grounds, a multimeter is a waste of time, IMO. We used 120 Volts AC as do all the professional re-builders, IME.

Schottky diodes are an interesting concept in terms of rectification as it would be ideal to reduce the forward bias by over one volt in each diode of a rectification pair. The power loss and heat are significant.

HIH

Norm

[Smellii]

Norm,
Have to take a break today to get caught up on chemistry and statistics. I'll perform the headlight test probably tomorrow.

[Smellii]

If the R/R is removed and stator wires detached I can still ride the bike in the mean time for short jaunts right? As I understand it the electricals will be running strictly off of the battery until it runs out of charge, correct?

[koolaid_kid]

If you want to ride it, reinstall the R/R first.

[Smellii]

Ok really confused once again. I go to install my old R/R just so I don't have to drive my buick around town today and realized if I install it the way I think it needs to be installed then I have two wires in the wiring harness without a mate. Here's what I've got:

Three black stator output wires plug directly into the three R/R input wires.


Next the red output R/R wire plugs into this red wire from the wiring harness. (Ground from R/R to be properly grounded of course) and that takes care of all the wires from the stator and R/R but see the green/white and the orange/white wires in the harness? They have no place to go??? I know there were connected to something when I started but can't figure it out. Sorry for the trouble guys.

[Steve]

That's actually a red/white wire (not orange) and you can ignore them.

They origiinally went to the headlight switch so that part of the stator would be disabled when you turned off the headlight, but, since you can't turn off the headlight, they were re-routed to just come back down. You are better off by connecting directly from the stator to the R/R inputs.

.

[Smellii]

got it! thanks.

[tom203]

I'm not sure that I understand your point Tom203, could you re-phrase?

Are you aware of the use of Schottky diodes in alternator rectification circuits? It was my understanding that they are a low power diode with high reverse current leakage so understood that they aren't used in rectifier circuits like for our bikes. The trick thing seems to be a controlled MOSFET although there may be an advantage to use of a Schottky diode for controlling the MOSFET but this is going out of my depth.

If you are stating that even the low cost meters are reliable for testing Schottky diodes then I accept the point as have no experience in that regards.


Norm

I know little of Schottky diodes- my point was that the cheapo meters are a useful tool that won't intimidate a novice mechanic. Having a quick method to check a R/R rectifing circuit is handy. I have two R/R's that fail this simple test, so the meter has earned its $10 pricetag!

[Normk]

Hope I'm not creating the wrong impression as am simply interested and not intending to appear argumentative or nit-picking.

Your point regarding the low priced meters available today is well stated. I do see problems from time to time when people use diode test functions and especially when they use an ohmmeter to test diodes. That's why I mentioned the use of a 12 volt source and light. Your point that some of the low cost meters are less likely to intimidate a novice is well stated.

Too often people acquire instruments which are excessively complex which adds to the difficulty in learning to use.

I know little of Schottky diodes either excepting what I stated. It is my understanding that they have very low forward bias voltage drop in small current applications although the ones I spec'd out through Mouser and other sources seem to indicate a full load drop which is as high as that of silicone diodes. I was hoping to have someone clear up the subject as one never knows who is reading these threads.

I like the idea of a lower forward bias as I want to believe that a smaller voltage drop will translate into more alternator output, despite that theory shows it won't. Just one thing I won't be happy about until I try it and fail.

The best physics explanation I have heard was in response to a question which starter out something like, "This is off topic and someone would have to be a rocket scientist to understand this but...."

Back came a long but wonderfully crafted explanation which a 4th Grader could follow right up and beyond my college physics and into the realms of high learning. They fellow started out with something like, "Well, I do work for NASA in research & designing space so, loosely stated, I guess I'm a rocket scientist...."

One never knows..... It certainly never hurts to ask and often hurts if one gets onto a high horse. Short people such as I have a long fall.

I know little of Schottky diodes- my point was that the cheapo meters are a useful tool that won't intimidate a novice mechanic. Having a quick method to check a R/R rectifing circuit is handy. I have two R/R's that fail this simple test, so the meter has earned its $10 pricetag!

[Smellii]

Received the R/R in the mail (Woot! Thank you, Good Sir) Hooked it up without crimping connectors to the wires (cuz I don't know if they are crimp-type) and got a 13.5V reading at the battery terminals. Seems to work great now. So freggin excited! Thanks for your help, Fellas. Just need to find out exactly how to properly connect the connectors to the wires and I'm good to go.