Testing a rectifier.

From what you just said, you hooked it up wrong.
Lets start with the right things you did.
3 whites to 3 yellows
Red to red, battery positive.
The blue to switched power.
Every thing else is wrong.
On your 78 You don't send power to the right brush. On the 78 it's grounded,
You don't use the nylon screws. This prevents grounding.
On the rest of the wiring the green from the new reg/rec is ground. The orange from the reg/rec hooks to the green wire to the brushes.
It seems you didn't follow the directions Mike's gave you.
You can try another from Mike's and try following the directions. That's another $99.
On any bike you can't use generic aftermarket parts and keep it original.
Leo
 
Ok I get it... Wish I'd asked you guys before toasting up a benjamin $100 . Going redo the the wires and ground both brushes and then get on line and buy the vr 115 . Because we all know if theres smoke its too late thanks to you both stanh
 
Hello Mr Retiredgentleman, Hope you all had a Merry Christmas. I have the 78 model with the charging problem. After torching the $100 all in one reg rect,I finally listened to you and bought the vr 115, and Rad shack 276-1185 rectifiers. So I don't do something "else" stupid, I was clear on everything, heat sink, and such, except the stator brushes with this set up. I see you say the green from the reg. goes to the left outer brush. Does it bond to the stator " or ground" to the stator. I have the new stator from mikes. Also was not clear on the other inside " right brush". So, other than the brushes all the drawing and your instructions are clear to me. I just would like to 100% sure before I screw up again. Thank you very much, Slow to listen stan
 
On the 70-79 bikes the left/outer brush is not grounded. It has a green wire that goes to the regulator. The right/inner brush is grounded to the stator by three of the mount screws. It also has a black wire that runs up into the wiring harness ground.
Mike's stator has different colored wires on it so you need to look closely and see what color wires hook to which brush.
A quick run down on how the reg works.
When the battery voltage is low, below 14.5 volts, the reg sends full battery voltage out on the green wire to the brush. This voltage goes through the rotor and out on the other brush. This brush is grounded. This voltage flowing through the rotor creates a strong magnetic field in the alternator. This magnetic field is what excites the stator into producing electricity.
No power flow through the rotor = no charging.
Leo
 
Hello Mr. xs Leo and or Mr. Retiredgentleman, I have the 78 mod and vr 115 and rad shack rects. I hooked up the rects " seemed pretty clear to me". I hooked the vr 115 regs orange and the yellow to the brown wire from the key switch. I have the black from the vr115 hooked to a good negative. The green from the vr 115 is going to the left brush on the stator. My understanding is that the vr 115 reads below 14 volts and it sends full voltage on that left "ungrounded" brush. I didn't get any voltage {out } of the vr 115 green wire. Sure was thinking I'd see 12v coming out on the green from the reg. What does this mean? Thanks you both for all the help in the past. Finally getting around to this project after months of just looking at her. stan
 
Mr. Retiredgenleman, this is Stan with the 78 mod and the guy who burned up the 100 dollar rect reg all in one. I have done as you suggested and got the 2 radio shack rects and the vr 115 regulator. I hooked up vr 115 I thought as you informed me. I have hooked the regs orange and yellow with the switched brown from the key. The black to a good neg ground. I took the green out of the reg to left outside "ungrounded" brush on the Mikes xs stator I bought. The other inside brush is grounded to motor and to a good neg. I ran the motor and did not get any voltage "out" from reg on the green. I should get 12 v. out on green right? Have road 15 miles in 5 month all from this one problem. If you could help again I'd sure appreciate it. I owe you all very much and hope that I will be able to help somebody in the future. Thanks no charge stan
 
When you turn on the key, you should see a voltage of about 11 to 13 volts appear across the 2 brushes on the alternator. That same voltage would give a strong magnetic field, and a feeler gauge or other metal object should be attracted to the rotor.

Maybe start at the basics: Remove the brushes. Does the rotor resistance measure around 5 to 6 ohms from slip ring to slip ring? What is the resistance from either slip ring to the alternator steel frame...............its should be very high.

You seem to have it wired correctly, so why you don't see 12 volts on the regulator green wire (same as the outer left brush) is a mystery to me. Are you sure all connections are good? Are you sure the regulator's black wire, and the right inner brush are both grounded to the frame....................use an ohmmeter to confirm zero resistance measured from both those points to the battery negative terminal.
 
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Mr. Retiredgentleman The rotor is new one from Mikes xs that measure out between 5 and 6 ohms. I will double check my connections. I'll check the black ground wires resistance also. I appreciate you "hanging in there " with me through this "ongoing" no charging situation. Springs coming and with it the strong urge to ride. If I don't get voltage on the green after checking connections I will just get another vr 115. At least they aren't a 100 dollars like the all in one rect reg. Thanks again and have a great day, stan
 
Mr. Retired Gentleman, I bought another vr 115 and installed it. It has 12 volts coming out on the green to the left outside ungrounded brush. I started the bike and checked the battery voltage. At 4k rpm it went all the way up to 16 volts. Is that too high? Or is that how it should be? Thanks stan
 
Mr. Retired Gentleman, I bought another vr 115 and installed it. It has 12 volts coming out on the green to the left outside ungrounded brush. I started the bike and checked the battery voltage. At 4k rpm it went all the way up to 16 volts. Is that too high? Or is that how it should be? Thanks stan

Stan, if it wasn't for bad luck, you wouldn't have any luck at all:)

Yes, 16 volts is to high. 14.1 is the desired voltage, but 14.5 is still acceptable.

Do you have the orange and yellow wires from the VR115 connected to the load side of the ignition switch? When running the engine, what voltage do you measure at the load side of the ignition switch? If that voltage is to low (voltage drop across the ignition switch), the regulator will increase voltage to the rotor and cause the high 16 volts.

Its important to have some load for the alternator. Do you have the tail light and headlight on when measuring the 16 volts?

The 12 volts to the outside brush is normal when the engine is at 1200 rpm. However, as you rev the engine to 3 or 4 k rpm, that voltage should reduce to 5.5 to 7 volts. Connect your VOM to both brushes and read the voltage as you rev the engine to 3 or 4 k rpm.
 
Mr. Retiredgentleman, I made a bad mistake... I bought a battery from Wal mart and it only will charge to 11.8 v. With the taillight on its even lower at the brushes. The reg. is probably over compensating for the " lack of voltage" on the brown switched wire. So if it sounds like that may be the case, what kind, and where do I buy a good battery? Whats your recommendation? Thanks again stan
 
Yes, Walmart is likely a poor choice to buy a battery. I'm not familiar with your automotive/bike suppliers in the USA. Usually you get what you pay for, so best to keep away from the lowest cost batteries.

The charging system will only work properly if the battery is doing its job. Always charge a new battery on the bench until its fully charged.

I like to use a lead acid battery of 14 amp/hr. When a lead acid battery is fully charged, it should read about 12.5 volts.

The battery I have now in my bike, is from Canadian Tire, which is an automotive/hardware store, located everywhere across Canada. Its 7 years old and works great. I use electric start and it always gives instant start on my bike.
 
I've gotten Yuasa batteries from Advanced Auto, TSC, Tractor Supply Company, In case you didn't know what TSC meant.
Most any place that sells batteries sells one that will fit.
The important thing is that 14L-A2, there may be other letters and numbers before and after, but besure it has those in there.
If you take your Wal Mart battery with you, look at the differences between it and a better battery. You can see how much better the new battery is.
After replacing my battery in the 75, I can't reccomend the Ballistic Battery, The 8 cell is smaller, lighter and more powerfull than any lead acid battery. It cost more, but I think it was worth it.
One thing, on any new battery you need to follow the instructions on filling and charging to the letter. If not you get a battery that won't fully charge or have it's full power.
Upgrading from a regular battery to a sealed battery is worth it. No messing with keeping it full of water.
The AGM, or Absorbed Glass Mat uses fiberglass mats between the plates. This holds the liquid and helps support the plates. These types of batteries hold up better than flooded batteries. They with stand being discharged and recharged better.
I might suggest googling batteries and doing a bit of research on the different types and the pros and cons of each.
Leo
 
Mr. xsLeo , thanks for the info. I am looking for the AGM batt as you suggest. Hopefully this will fix the charging problem I have had for many months now. thanks stan
 
I looked around my town and could not find that battery. I see one on Mikesxs site part no. 61-2020 AGM that say it replaces the yb14L-A2. Will that one suffice? Only $65. thanks stan
 
I looked around my town and could not find that battery. I see one on Mikesxs site part no. 61-2020 AGM that say it replaces the yb14L-A2. Will that one suffice? Only $65. thanks stan

I have never owned an AGM battery. so I can't comment on it. However, a friend of mine had bought an AGM for his 1976 XS650, from Mikesxs, and it crapped out in less than a year.

I use a 14 amp/hr lead/acid battery, because it has always worked for me over the last 7 years.
 
I went online and after viewing a dozen sites, I went to Batterymart.com and found a AGMatt battery with 220 cca and the 14 amphour rating. $72 and free shipping. Strongest AGM I could find in that size. Free shipping. Maybe this can send me on the right path with my charging issues. At least I'll know its not the battery making it over charge voltage wise. Thanks to you all, stan
 
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