Voltage Regulator/Rectifier Replacement

VMAX  Forum

Help Support VMAX Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
man, I hate wiring.. I see your pic but I don’t really know what’s what. So bridge my hot wire to the R/R hot wire like it was & the key switch wire? Which wire is key switch wire? Any how-to videos on this? What is that relay or whatever you’re holding in your hand?
 
Last edited:
That’s true, your stator and connections should be good based on your previous voltsge reading. So try jumping and check your grounding. If that gets your voltage up, Repair main fuse including the crimp mentioned. That crimp is in between battery and splits off to r/r and key switch.
Btw- it does have ground wire going from bolt of R/R directly to negative post on the battery. So grounding should be good.
 
Look at the pics, that's why I included them. Remove the wire loom tape to expose it. A quick solder session and you should pick-up > 1 volt to the harness.
man, I hate wiring.. I see your pic but I don’t really know what’s what. So bridge my hot wire to the R/R hot wire like it was & the key switch wire? Which wire is key switch wire? Any how-to videos on this? What is that relay or whatever you’re holding in your hand?
Also, will this wire bridge divert the 30 amp main fuse or still be protected by it?
 
Last edited:
I see your pic but I don’t really know what’s what. So bridge my hot wire to the R/R hot wire like it was & the key switch wire? Which wire is key switch wire? Any how-to videos on this? What is that relay or whatever you’re holding in your hand?
Also, will this wire bridge divert the 30 amp main fuse or still be protected by it?

First step to understanding this would be to get a wiring diagram so you can see which wire goes where.
In the circuit we are discussing none of the wires are switched; it goes from the battery to the main fuse then splits (a.k.a. 'The Splice') to the r/r and to the ignition switch.
With that set-up any short circuit will be protected by the fuse. Taking a wire from the r/r to the battery +ve without a fuse (a.k.a. a bad idea) would result in significant damage in the event of a short circuit.
You could include a fuse to give protection but all that wouldn't achieve anything that the OE wiring is doing assuming it is in good condition.

I don't know of any video's but the attached may throw some light on what you need to do.
 

Attachments

  • Splice Fix.pdf
    260.2 KB
Here's another link: Lvlhead's Vmax - The Splice

The fuse block he's holding is the main fuse (sub fuse). There's a grommet around the main fuse box and you should see that mounted on a tang that's part of the coil bracket. It's near upper left of battery. The blue wire is bypassing that and the splice. On the main fuse, one wire goes to the battery and other goes to splice. Disconnect the R/R red wire connector and hook your voltmeter up to the R/R side. Start bike and measure the voltage coming out at idle. That is your potential charging voltage. Measuring again at the battery with the R/R connected again shows how much voltage you're losing between the R/R, crimp, main fuse, to battery.
 
First step to understanding this would be to get a wiring diagram so you can see which wire goes where.
In the circuit we are discussing none of the wires are switched; it goes from the battery to the main fuse then splits (a.k.a. 'The Splice') to the r/r and to the ignition switch.
With that set-up any short circuit will be protected by the fuse. Taking a wire from the r/r to the battery +ve without a fuse (a.k.a. a bad idea) would result in significant damage in the event of a short circuit.
You could include a fuse to give protection but all that wouldn't achieve anything that the OE wiring is doing assuming it is in good condition.

I don't know of any video's but the attached may throw some light on what you need to do.
Thx. That should be sufficient. I had the previous wiring diagram listed above in the main thread but I didn’t see the ignition switch lead listed in that diagram.
 
Here's another link: Lvlhead's Vmax - The Splice

The fuse block he's holding is the main fuse (sub fuse). There's a grommet around the main fuse box and you should see that mounted on a tang that's part of the coil bracket. It's near upper left of battery. The blue wire is bypassing that and the splice. On the main fuse, one wire goes to the battery and other goes to splice. Disconnect the R/R red wire connector and hook your voltmeter up to the R/R side. Start bike and measure the voltage coming out at idle. That is your potential charging voltage. Measuring again at the battery with the R/R connected again shows how much voltage you're losing between the R/R, crimp, main fuse, to battery.
Thanks, I know where it is now. Thanks 🙏 for all the help guys!
 
Last edited:
Here's another link: Lvlhead's Vmax - The Splice

The fuse block he's holding is the main fuse (sub fuse). There's a grommet around the main fuse box and you should see that mounted on a tang that's part of the coil bracket. It's near upper left of battery. The blue wire is bypassing that and the splice. On the main fuse, one wire goes to the battery and other goes to splice. Disconnect the R/R red wire connector and hook your voltmeter up to the R/R side. Start bike and measure the voltage coming out at idle. That is your potential charging voltage. Measuring again at the battery with the R/R connected again shows how much voltage you're losing between the R/R, crimp, main fuse, to battery.
Can I just splice the blue wire to that main fuse Culprit red wire, since that goes to the crimp connection? (W/o having to undo the wiring harness to get down to the crimp.) Wouldn’t that do the same thing?

Or better yet, if I just install a heavy fused wire from the battery to the R/R? Wouldn’t that do the same thing?
 
Last edited:
Can I just splice the blue wire to that main fuse Culprit red wire, since that goes to the crimp connection? (W/o having to undo the wiring harness to get down to the crimp.) Wouldn’t that do the same thing?

Or better yet, if I just install a heavy fused wire from the battery to the R/R? Wouldn’t that do the same thing?
You can do the first assuming the main fuse block isn’t causing the charging issue.

Second option would fix your charging. But crimp may still be an issue and cause voltage drop to rest of electrics….system, lights, ignition, etc.
 
I have posted here about the benefits of changing from the stock "shunt" units to a modern SERIES type regulators. I have one in my '85, and charge at 14+volts at any engine speed over an idle.
 
I have posted here about the benefits of changing from the stock "shunt" units to a modern SERIES type regulators. I have one in my '85, and charge at 14+volts at any engine speed over an idle.
..hello...please "part name" or manufacture...sorry,maybe I have to look in a "post of regulator"?.."charging system"..thank you in advance Bill...
 
Last edited:
Check out this supplier: R/R Connectors

And a manufacturer: Regulators/Rectifiers | Motorcycle Products | SHINDENGEN ELECTRIC MFG.CO.,LTD

Not about a VMax, but it shows a motorcycle installation and common problems being solved conscientiously. MOSFET voltage regulator upgrade

From one of our former members: How to: Fix your Vmax's low voltage or charging problems Very helpful, lots of discussion. He still checks in from time to time.
🍻thank you Fire-medic...as usual very helpfull
 
Watch those cheap regulators from EBay or Amazon.. 100% fakes, and prone to fail. Be certain its a genuine Shindengen. Also, spend a few extra bucks and get a Series type unit. It is a better design than the MOSFET type.
 
I did the Shindengen R/R upgrade on a 2007 Speed Triple. The speedies were known to blow alternators because the stock regulator would run the alternator at 100% all the time and shunt the unneeded power off as heat thru the cooling fins. The Shindengen unit only runs the alternator as hard as it needs to to supply the load so the alternator remains cool. The Shindengen is a MOSFET regulator. They apparently charge better as well. If you want more info Google Shindengen and Triumph Speed Triple and there is a very complete article. Triumph corrected this in the next generation of Speedies.
 
Last edited:
My apologies - the Shindengen is a MOSFET type regulator and the stock regulator is apparently an SCR - series type. I don’t want to get into a discussion as to the merits of either type, but the Shindengen is what Triumph used as a warranty replacement for the stock unit and as an upgrade in the next generation.
 
Last edited:
I bought Virago with "bad charging system", it turned out, one wire lost insulation and was touching cover. 2" of electrical tape increased bike value about 4x. It was 920, very popular for modders, buyer didn't even start engine! I fixed wire for nothing!!!:mad:
 
Bill how does the Series type get rid of the extra voltage?
Opening the circuits from the stator phases. Don't know exactly how it is done electrically, but it does not shunt to ground. In effect, shunting to ground is like a dead short. Makes lots of heat..
 

Latest posts

Back
Top