15.2V /1500 RPM. Is it too high?

I installed generator from 81 KZ1000, it is bigger than original.

So I regardless of size, it should be maintaining the same peak charge voltage as your old charging system. Larger alternators have increased current (Amperage) capacity not higher voltage. Based on a 12 VDC battery system, your charge voltage should be in the neighborhood of 13.5-14.5 VDC range. Your's being 15.2, I am not sure the accuracy of your measurements, but if the voltage regulator is faulty or has poor connectivity on the feedback within in the regulation circuit, it will drive the voltage regulator wide open like you are seeing now. I would start by ensuring you are using a fully charged battery and both the positive and negative cables are tight and corrosion free. I am assuming the parts you are using are used? I would begin by checking your charging system and its components per the factory service manual going over winding resistances, etc to ensure your system is functioning normally. Unless you are operating on a very low or faulty battery, that constant wide open charge voltage is not right and maybe the reason you changed parts in the first place. Maintaining the high output all the time will just create heat and is hard on both the battery, but also the stator and voltage regulator.

Cory

Yes, 15.2V at 1500 rpm is too high. Your voltage regulator isn't regulating.

A wiring check is in order and if that checks out, a new R/R. The SH775 is the best unit going these days since it helps protect your stator from cooking. And speaking of cooking, that high output "generator" you installed will result in the stator running hotter than normal, and these units don't need any more heat than they already see. Basically, all excess current produced by the generator that isn't consumed by the bike is shunted back to the stator where it can cause damage. The SH775 is a series R/R so it stops the shunting process and subsequent stator stress.

+1 on Ed's advice...it works.

Maybe that's why the coil cracked.
Steve

Nessism wrote: Yes, 15.2V at 1500 rpm is too high. Your voltage regulator isn't regulating.

A wiring check is in order and if that checks out, a new R/R. The SH775 is the best unit going these days since it helps protect your stator from cooking. And speaking of cooking, that high output "generator" you installed will result in the stator running hotter than normal, and these units don't need any more heat than they already see. Basically, all excess current produced by the generator that isn't consumed by the bike is shunted back to the stator where it can cause damage. The SH775 is a series R/R so it stops the shunting process and subsequent stator stress.

Ugh... mine is doing that now too... about 400-500 miles into three or four rides and my battery water is below low level, and boil out. With my Fluke DVMM is exactly 15.4vdc at 2200 rpm.

Bad ground?
Steve

It's a shunt regulator system. If you put on an alternator with a lot more output current, it's POSSIBLE that the shunt reg can't handle the extra current. The reg could be smoked, but I would want to use the reg assembly that was designed to work with that alternator.

SH775, Polaris part number 4012941
Triumph wire harness - T2500676

If money is tight you can get a used SH775 from ebay for about $45. They are extremely robust units so no worry with used. Search out Polaris Ranger or RZR Regulator. Just be sure to make sure you see SH775 printed on the unit in the photos. These SH775's are getting popular so there are some clone ripoff units on the market now that look the same but aren't. You can also use regular spade terminals to connect to the unit. After install fill the cavity on the R/R with silicone.

IF the reg has a sense line (brown wire), you should check the voltage on that first. IF the voltage on the brown wire matches the voltage on the battery, then it's likely the regulator. If the brown wire is lower than 14.3, but the battery is still above 15, then you have to locate the source of the voltage drop.

loudhvx wrote: IF the reg has a sense line (brown wire), you should check the voltage on that first. IF the voltage on the brown wire matches the voltage on the battery, then it's likely the regulator. If the brown wire is lower than 14.3, but the battery is still above 15, then you have to locate the source of the voltage drop.

^This.....

Cory