How to: Fix your Vmax's low voltage or charging problems

VMAX  Forum

Help Support VMAX Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Why buy a fake new one when you can get a real used one for less than half the price? I think I paid $20 shipped for one off a ZX-14. What bike it came off is pretty much irrelevant.
 
Guys,

mine charges 12.5 at 1000 rpm.
13.2-4 at like 1500-2000 rpm
And drops down to 12.2-4 at 3000 rpm or higher.

strange right?
Any ideas?
 
What is the raw AC voltage to each of the three white wires. Your max DC voltage will not exceed that number when converted from the regulator (the most common part to go bad).
 
A 2007 should have the updated R/R part. Which isn't to say it's not the issue, but it's a bit less likely.

If it's the original battery, that's a likely culprit. These motors take a lot of amps to crank over, especially when hot. The stock battery is just barely up to the job anyway, so any loss of cranking amps shows up.

If you go back, bring a multimeter and check the voltage as detailed in the first post...that'll tell you if there's an issue with the charging system. If the voltage is anything less than peachy, use that to barter the price down a bit.
Torco Oil with 1200 parts per million Molydium and the other 8th Air Corp chemistry to fight Luftwaffa 109s makes a difference when the battery is weak. You could lose all the coolant and make back from anywhere trust me It's been done.
 
I would grab more pictures, though I sold my Vmax late in 2012.

I have taken a few calls from members about this thread since it was posted, if there's something you're still not clear about you can contact me via PM or phone and I'll do my best to explain it in better detail.
Can you help me please?
 
I replaced my AGM battery with a lithium battery. Everything works better and no need to keep the bike on a trickle charger. The lithium battery is guaranteed for 3 years. I ran into a fellow VMaxer at a fuel stop in Albuquerque and he saw me waiting for the bike to cool in order for it to start. He recommended the lithium battery and uses them in a Gen1 and Gen2. Expensive, but worth it.
 
I can't see the pictures for his zx14 R/R so which side is ground and which one is postive to battery?
 
I can't see the pictures for his zx14 R/R so which side is ground and which one is postive to battery?
If you’re waiting for a cool down to start, I suggest checking out your starter condition if you already have a good battery, they will lose the ability to ground after years of use and will hate hot starts, search for threads on this have done it before and makes a big difference. Cheers to you.
 
I did a version of MaxMidnights attachment for the hot start fix. I took the starter apart and cleaned everything and made a stud and mounted it to the brush holder that went thru the back cover (drilled hole) and nutted it from both sides. Have not had any issue with starter since.
 
If you have to wait for a cooldown before the engine will turn properly to start then it means your battery is either on it's last legs or isn't charging. The reason you have to let it cool is if you turn on the ignition of a hot engine then the radiator fan will start straight away and so draining a few amps from the battery before you even hit the start switch. I'm talking from experience.
 
I thought I fixed my charging problem years ago with new stator and reg/rec. I just had to jump start it even though it was on a battery tender so my battery might be bad also. Wouldn't crank so I checked voltage, 12.68v. Jumped started it and at high idle it read 12.2v. At regular idle, 13.2v. Rev'd it up to 2500-3000rpm, 11.3v. Any ideas? Also, what lithium batteries are you all using? Even with a battery tender I can't get over 3 years from a battery.
 
I had a similar problem this spring. Checking the R/R I found a bad diode-replaced R/R and still had issue. Checked stator and had .42 ohms leg to leg. (Fluke 189 meter). I got .1 ohms when going from 1 leg to ground on each. I had 50-60 volts reving engine with stator disconnected. as soon as I plugged in the stator the voltages dropped to 12.2, 10.9, and 9.2 volts when reving engine. It ended up being a shorted stator. Replaced stator and now it runs at 14.2 at idle.
 
Excellent write up for this issue. This post is going to be long winded so please bear with me. My ‘02 V-Max died at a stoplight after taking it in for inspection, it had been sitting for a few years with only the occasional startup and ride around the block to keep things lubricated. My daughter caught the motorcycle bug at the age of 21 and wanted to ride together so I dusted off the old beast and began refreshing things. New plugs, filters, all the fluid changes, and a new lithium battery. After my Max died and getting it towed home I began testing the electrical system and found the stator was dead, I’d been running off the new battery until it was sucked dry of go-juice. I also replaced the regulator/rectifier out of caution since I didn’t want to do it later, the bike has over 40k miles. Now the questions for those masters of the beast. Please reference the two photos.

1. In the first photo of my cover and the new stator in place (without the retaining ring on the stator yet, just a trial fit) there is a tab under the screw labeled ‘1’. In my Clymer V-Max service manual it’s not listed in any parts diagram or shown in any photos, nor is it anywhere in the factory manual I downloaded. I’m 99% sure that’s where it came from (because of moving my two daughters back to college it sat for a couple weeks after disassembly.) What is the tab for and do I have it installed correctly?

2. Same first photo, there are two unused screw holes labeled ’2’ and there wasn’t anything there when I took it apart. However, in the second photo, of my Clymer manual for the stator, it only shows one bracket in the top parts diagram (photo cut off at the top) but has a second pickup bracket in the manual photo at the red arrow at the bottom of the page. Should I have a second pickup?

Any information that can clear this up is is greatly appreciated, this forum is the ultimate source for our legendary beast!
 

Attachments

  • IMG_1696.jpeg
    IMG_1696.jpeg
    1.1 MB
  • IMG_0145.jpeg
    IMG_0145.jpeg
    1 MB
'85-'89 bikes used two pick-up coils. The 1990-'07 bikes used one.

The '85-'89 bikes have five wires from the two pick-up coils. The 1990-'07 bikes take two wires. The cdi box is different, and the wire harness too, The rotor is different for the electrical stator/rotor assembly.

1725331471067.png

1725331813458.png
 
Last edited:
Back
Top