rectifier issues. There has to be a better way.

[cpmaynard1980]

This is about my 850 but I think this applies to the 1100 also.

So my 850 left me stranded on the side of the road with a dead battery. The battery is a month old sealed glass mat battery and its fried. Wont take a charge at all. Im looking through the bike and all appears to be normal with the exception of the rectifier plug that has a melted area on one of the connections at the plug and corrosion on the connections. i checked both of my other 750 and they have the same issue with the plug. I checked the 1100 and it has corrosion and it looks like it started to get hot.

Looking at the 1100 and these bikes are very close to each other and Im thinking to myself that there has to be a more effective way of fixing this issue that appears to be very common among these bikes.

what are other options that you guys have seen. Im not sure if this plug is the cause of my problem but its something I noticed. How could I take a reading on the rectifier to see if its still good? Same with the stator.

[CaptonZap]

In the 1980 second edition of the Clymer manual, on page 164 and 165, you will find the method that Yamaha advises to check the rectifier.

Or go here,

http://www.ringler.us/family/mybike.html,

and read the electrical section, wherein will be explained all sorts of tests for various electrical components.
I would imagine that the same components would be used across a wide range of Yamaha bikes.
YMMV
CZ

[motoman]

A common AND most neglected problem with all older bikes. Imagine bad connector causing resistance and then overcharging rate which AGM's do NOT tolerate at all. Surprised if regulater is not toast also.

[skids]

At those connectors behind the fuse panel, this is the maximum voltage that can occur. Higher voltages means arcing and heat if the VR is bad or the connections are bad. The only way to improve this is to ensure that the VR/rectifier is working properly AND to ensure that the connections are good. Bad connections trick the VR/rectifier to making more charging, causing arcing and melting plastic.

I am not an expert in these matters, but I have resolved the same issues.

[GLoweVA]

I just looked it up and the 750's, 850's and the 1100's all share the same rectifier, so IF your 850's is fried, then finding a replacement should be easy.
(Heck I might even have one in my stash, I'll look this weekend)

As to your failure, I guess during our ride, the alternator output wasn't getting back to the battery and that's what drained/killed you battery.
I can't remember if your tach works or not. If it does, then that may be a good sign that your alternator is working, but best to put a meter on it to be sure.
The manual has a good write up on how to check the alt and rect.
Do you have a hard copy of the 1100 manual? If not I can probably print one out and bring it by and show you the steps/pages where the tests are located.
I helped John replace his regulator early in his build. (thinking about it, the extra one I'm thinking I have may be his bad one, I'll double check)

[GLoweVA]

I had a brain fart. Your 850's tach doesn't come off the alt, it's cable driven. OOPS!

[cpmaynard1980]

No i don't have one for the 1100 but i think i have a one for the other bikes. now that my connector is messed up would it be better to mount thermal blocks or something back there so i could clip off the old terminals and put on new ones? I was given an extra rectifier that looked like new but when i went to remove the connectors fRom the plug for cleaning the first one broke with the slightest pull after poking the little tab down. The fuse area is also a hot mess.

[GLoweVA]

Alright Charles, I'll print out an XS11 manual for you and swing it by your house.
As for the replacement plug.... I'm outta ideas.
Maybe someone here has done a connector replacement with something off the shelf that will work without melting.

It's got to be able to hold up to the slightly higer AC voltage (like 16VAC) and probably a good 35-40Amps (divided by 3 for each phase, so about 12-15Amps per conductor/connector) (obviously we're talking about the 3 stator white wires and not the Tan and Dark Green for the field)

[cpmaynard1980]

Well i got bike running again. Replaced the rectifier and had no spark so i pulled the ignition Box off of the parts 750 and it fired right up. But i think there's contact on the coil and that piece that rotates under the stature cover. Lower end also sounds ruff at low idle. Going to change oil and filter and hope it helps. :-)

[GLoweVA]

You may want to take a look under that alternator cover.
The melted plug at the rectifier, may just be a sympton of something else that went wrong.
If you remember during our ride, you heard something about mid afternoon that sounded amiss. That might have been the rotor rubbing on the stator or something like that and thus causing the alt output to ramp up and melting the connector (and maybe the TCI too)
Have you checked the stator and rotor for ohms? and resistance to ground?
You may have spark now due to a good battery, (and TCI) but is your alternator putting out the right voltage?
I think it's about 14V at 3Krpm.

I'll swing by later this afternoon after work and drop off the 11 manual.

[cpmaynard1980]

Ok thanks.

[DiverRay]

Replacement connectors can be had from http://oregonmotorcycleparts.com/ The owner is a member here, and he also builds VERY GOOD replacement reg/rectifiers for Japanese bikes.
I would say treat the 850 like an 1100, replace fuse block, clean and check ALL connections, and maybe spend the $140 or a new reg/rec. Do a search and I think most of the threads are still here.

[crazy steve]

As for the replacement plug.... I'm outta ideas.
Maybe someone here has done a connector replacement with something off the shelf that will work without melting.

It's got to be able to hold up to the slightly higer AC voltage (like 16VAC) and probably a good 35-40Amps (divided by 3 for each phase, so about 12-15Amps per conductor/connector) (obviously we're talking about the 3 stator white wires and not the Tan and Dark Green for the field)

The AC output voltage is more than 16 volts..... probably closer to 30. But that's not an issue. You do need a connector rated for at least 20 amps, more would be good. That's one reason these fail, is the stock ones are good for about 20 amps max and bad connections can easily reduce that to less than what the alternator puts out....

The ones Geezer sells (see post above) are good for 20 (but no more), so make sure they're installed right.