Voltage?

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Eugene Brad

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Hey every one I know I could have looked around a little more than I did and answered my question. But i figured a quick question would yield a quick answer. What voltage should my battery have not started? And at idle? Happy cinco de mayo!

Don't worry I'm not riding tonight
aef367aa6b2e038dff4388144d9cc2eb.jpg


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12.8 V I believe, and if it drops much below 11 V starting, I believe that's a weak battery indicator.
 
So I was riding my 85 for the first time as actual transportation and not joy riding. Topped it off at the gas station. Zeroed the trip odometer and set out for a friend's house where we play music on Wednesday's.
After about 18 miles of speeds between 55-85 at the first stop light bike had a low and iregular idle with an intermitten pop at the exhaust. So I kept a little throttle to it to be sure it didn't die at the five or six lights I had to get through to get to where I was going. At 20 miles into the trip I pulled into a market to grab some beverages. As I pulled the clutch in to stop at the market the bike died.
Started right up for me on first try to leave the market but wouldn't idle and died. And after that battery went flat and would not turn bike over enough to start.
Luckily friends house wasn't far and he came by and jumped me.
So, temp outside was hotter than I'd ever riden bike in at about 80. And I did end up spitting some coolant from overflow.
So...I guess my question is can the temp effect a batteries ability to hold a charge? The battery was new last year by the P.O.
I checked it last night it had 11.3 volts but would start the bike cold. It's been on the tender all night and now holding 12.6.
Can someone point me toward a thread or sticky that describes the testing and sequences I should go through to find my problem.
Fyi I'm no mechanic but I can follow directions.
Thanks in advance.
And thanks to Sean for taking my phone call Wednesday night to give a little confidence that I could probably ride bike and be fine to get home.

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So I was riding my 85 for the first time as actual transportation and not joy riding. Topped it off at the gas station. Zeroed the trip odometer and set out for a friend's house where we play music on Wednesday's.
After about 18 miles of speeds between 55-85 at the first stop light bike had a low and iregular idle with an intermitten pop at the exhaust. So I kept a little throttle to it to be sure it didn't die at the five or six lights I had to get through to get to where I was going. At 20 miles into the trip I pulled into a market to grab some beverages. As I pulled the clutch in to stop at the market the bike died.
Started right up for me on first try to leave the market but wouldn't idle and died. And after that battery went flat and would not turn bike over enough to start.
Luckily friends house wasn't far and he came by and jumped me.
So, temp outside was hotter than I'd ever riden bike in at about 80. And I did end up spitting some coolant from overflow.
So...I guess my question is can the temp effect a batteries ability to hold a charge? The battery was new last year by the P.O.
I checked it last night it had 11.3 volts but would start the bike cold. It's been on the tender all night and now holding 12.6.
Can someone point me toward a thread or sticky that describes the testing and sequences I should go through to find my problem.
Fyi I'm no mechanic but I can follow directions.
Thanks in advance.
And thanks to Sean for taking my phone call Wednesday night to give a little confidence that I could probably ride bike and be fine to get home.

Sent from my SM-G360V using Tapatalk
Sounds like a r/r.
http://vmaxforum.net/showthread.php?t=994
 
Thanks Jan bee. I'm elbows deep in yard work so I hope to get time to read up soon.

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So I began reading the chart to pin point my issue havn't gotten to actually checking anything yet. If it is my RR what can I expect to spend. A quick Google search got me a very wide range of price. Are used RR's an option? Itgoes, a member on the forum will sell me his but him and I don't know what it is worth and I don't know if it's smart to buy used. As always you alls help and knowledge is much appriciated.

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So I began reading the chart to pin point my issue havn't gotten to actually checking anything yet. If it is my RR what can I expect to spend. A quick Google search got me a very wide range of price. Are used RR's an option? Itgoes, a member on the forum will sell me his but him and I don't know what it is worth and I don't know if it's smart to buy used. As always you alls help and knowledge is much appriciated.

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Early Vmax regulators aren't very good. Easy to ID, They have no cooling fins. I'd use a later type or something else.
 
Check the 3 white wires from the stator going to the R/R. There is a white plug where the connection is made. It's not uncommon for that to be discolored brown or blackened, from a poor connection. If you see that, you will at least need to burnish the connectors and re-attach them. You may need to replace the plug, if any of the connectors are destroyed. Don't worry about this, easy to do, and it will eliminate a known problem.

You should also remove the R/R from behind the left rear footpeg mount and thoroughly clean to bright metal the connection, as this is another trouble-spot. The ground is made through this mounting point instead of a ground wire, which came later. Use some dielectric grease here upon reassembly.

Many people solder the white stator wires to the regulator/rectifier wires, eliminating the connector. The only time you need to access this connector is when your components are bad. Don't worry about the question of, "which white wire goes to which R/R wire?" as all three white stator wires can attach to any of the designated R/R wires. If you have to solder the new connector in place, you should consider just soldering the wires directly, and eliminate the connector. If you want to keep a connector, I suggest you solder the connectors to the wires, it makes a much more secure and corrosion-resistant electrical pathway. I suggest you use a male/female insulated 'bullet' type connector for each pair of wires. Whatever you do, ensure that the stator wires do NOT have any worn insulation along the path to the connection, and that you insulate them once you make the connection. If you solder the stator wires and R/R wires directly, eliminating the male/female plug, use heat shrink tubing for each soldered connection, and then wrap the heat-shrinked wires with a couple layers of electrical tape.

The MOSFET type regulator/rectifiers run much more cool than your early design unit, and provide better regulation of voltage.

A thread: http://www.vmaxforum.net/archive/index.php/t-31345.html

A supplier: http://www.electrosport.com/street-bikes/yamaha/vmx1200-v-max-98-07/yamaha-regulatorrectifier.html cost is $80, not bad.
esr280_1.jpg


Some reading: http://www.electrosport.com/technic...articles/how-motorcycle-charging-system-works

One for $70 from a known supplier: http://www.motorcycle-superstore.com/9169/i/ricks-motorsport-electrics-regulator---rectifier

0000-Ricks-Motorsport-Electrics-Regulator---Rectifier----MCSS.jpg


More reading: http://vmaxforum.net/showthread.php?t=2463

http://vmaxforum.net/showthread.php?t=19108
 
Good advice, but if you were going to spring for the upgrade to the MOSFET type regulator ( which I highly advise you do...), I would go one step farther and source a series type unit. They are a direct plug in to the FH012 or FH020 Shindengen units. I bought two used ones from Powesports nation for $40.00 each. Polaris ATVs use them, about $80.00 at a dealer. You'll need the proper Furukawa connectors. They're available online for around $10.00 EBay or Amazon. If you're not handy with soldering, you can get prewired ones from Eastern Beaver. Simple install, and they don't get hot. You can put them under the seat! I've got COPS, and the unit fits where the rear coils used to live. There are numerous clone knock off regulators on EBay, for as little as $15.00... People have had serious overcharging problems with these. The series unit is a Shindengen SH775. Roadster Cycles sells complete kits, either MOSFET or Series, with the connectors. I cut the connector to the stator right off and use Posi Lock connectors to the regulator. The output goes direct to battery. (through a good fuse).
 
Thanks a lot everyone. I hope to get time soon to do more than just read about my potential problem and actually fix it. Very helpful though.

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I can't help but ask the question, since you did state that the bike was hot (hot enough to spit coolant). Did you happen to notice the irregularity once the bike got hot? If so,, Did you notice if all felt good again, once the bike cooled?? Reason for asking.. When my coil pickup started showing signs of failing, the bike would start fine when cool. Then, once it warmed up, it started stumbling and acting erratic, then die out. It would not start again until I let it cool down. It would have these symptoms for a while, until the coil pickup finally died out, and the bike would not start under any circumstance.
 
I can't help but ask the question, since you did state that the bike was hot (hot enough to spit coolant). Did you happen to notice the irregularity once the bike got hot? If so,, Did you notice if all felt good again, once the bike cooled?? Reason for asking.. When my coil pickup started showing signs of failing, the bike would start fine when cool. Then, once it warmed up, it started stumbling and acting erratic, then die out. It would not start again until I let it cool down. It would have these symptoms for a while, until the coil pickup finally died out, and the bike would not start under any circumstance.
That is primarily how it went down, yes. I havn't replicated the issue yet. But yeah it started even with a low voltage at the battery(11.4 or so) once it cooled down the next day. I didn't ride though. Basically while hot it just couldn't quite turn the starter.


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That is primarily how it went down, yes. I havn't replicated the issue yet. But yeah it started even with a low voltage at the battery(11.4 or so) once it cooled down the next day. I didn't ride though. Basically while hot it just couldn't quite turn the starter.


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Was this on the 85? They do suffer from a hot start issue, so that might not be the underlying problem....but it sure wont help.
 

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