Charging problem

[Smunroe134]

Looking for some help as I am stuck with this thing. In regards to the charging system, bike will not charge. Everything seems to be wired correctly. If I ground out the green wire for one of the brushes the “slap test” is very good but the bike will not rev up (sounds like it hits a rev limiter anything past an idle). When I disconnect the ground for the green wire the “slap test” is bad (no ground to one of the brushes) but the bike revs up just fine. I cannot for the life of me figure out what is causing this or why the bike will not charge. I’ve tried swapping the stators as well as the rotor. Ive also tried both of the regulators I have. Any help is appreciated. Bike is an 81 with electronic ignition.

 

[jpdevol]

Welcome!

Are all the parts you mention above OEM or are some aftermarket parts involved and is the wiring config stock?
Do you have a multimeter available for testing?

 

[Smunroe134]

Thanks for the quick response. Wiring harness is chopped down to bare minimum due to this being a bobber build. Rotor is from mikesxs (slip rings continuity reads 5.3ohms off bike). Stator is also from mikesxs (phase wires read 1.0 ohms between all 3 white wires). One regulator is a mikesxs and one seems to be stock (no change between either one).

 

[jpdevol]

I thought from the description something unusual. Can you post a diagram of your wiring scheme? If not, perhaps one of the schematics from this post will sub. https://www.xs650.com/threads/some-wiring-diagrams.61/

My current theory is the grounds aren't right (guessing).

Is the ignition a Mike's e-advance perchance?

 

[Jim]

Have a read here.

Recommend you read it all, but you can skip forward to the resolution here.

 

[jpdevol]

Jim's post raises a question: is the other rotor you referred to a stock rotor with 5+Ohms between rings?
Next question: I looked over Mike's offerings and can't find a regulator compatible with a post '79 XS (other than a PMA thingy), so to keep from banging our collective heads, perhaps some pics (or p/n verification) of parts in question too, please?

 

[Smunroe134]

Jpdevol, just went thru all the wiring from one of the diagrams you attached. Double checked everything. Started the bike and it revs up like it should. With the bike running the battery sits at about 11.46v. After reading many forums I’ve learned that the rectifier/regulator will switch on the rotor depending on when it senses more charging is needed. My question to you is, at idle to half throttle is 11.46v normal? I’m a heavy equipment mechanic and I’m use to seeing a 12v charging system charge at 13 ish volts.

Jim, I read your attached article and it totally makes sense to me now. Before this issue the bike had a (what I believe to be) OEM rotor. That rotor only reads 1.3 ohms across the rings (on a bench) so I know that is an issue and could be the reason the bike stopped charging and left me on tje side of the road. If I have any more issues with this mikes xs rotor I’d be very interested in buying a re-wound rotor from you (if that is still something you do).

 

[jpdevol]

So we also need to address the regulator the points style cuts ground, the TCI cuts 12V - You might need the latter

Answer: No, you should be 14+ @3500, ~break even @ idle

Mike's offers 2 stock replacement stators; one for points style, one for TCI style

 

[Smunroe134]

After looking back I found that the regulator must have come with the bike as I did not purchase one from mikes. I do have a new regulator on order from tcbros part number 108-0007 which states it’s for an electronic ignition bike. Is 11.46v not a good reading? Should I be getting something closer to 13v?

 

[jpdevol]

The correct regulator from TC Bros for a TCI system (they call it CDI) is:
https://www.tcbroschoppers.com/coll...or-rectifier-yamaha-xs650-cdi-ignition-models

So I edited in voltage readings above. The TCBros regulator should work if you have the correct Mike's stator

 

[jpdevol]

I checked the book charge spec is actually 14.5 +-.5 @2000 rpm

 

[650Skull]

Using the correct terminology helps to make sure the people your talking to know exactly what you are working with...........

A 70 -79 US XS650 running a points ignition, (factory), and any Points, XS650, bike sold from the factory to other countries in the world up to and including 83 with factory points ignition has a Separate regulator and separate rectifier..................an aftermarket seperate SS regulator for points models can be bought, also an aftermarket SS combined Reg/Rect for points models can be bought

All XS650's from the factory that has a factory Electronic ignition, (TCI), has a Solid State combined Regulator/rectifier............and aftermarket SS combined Reg/Rect for a TCI model can be bought

just taking about a regulator on an 81 could make for confusion if some one wanted to enter the conversation

 

[jpdevol]

Perhaps I wasn't specific enough; the aftermarket sellers often just refer to year of application, so....

 

[650Skull]

Perhaps I wasn't specific enough; the aftermarket sellers often just refer to year of application, so....

Sorry, i was referring to the op............Post #1,3 just refer to a "regulator" or "both regulators".

yes the year of application, (from sellers), is also a issue when taking into account different ignitions were used on different bikes, (years/models), going to different countries/continents

 

[Smunroe134]

I will have to wait until the tcbros regulator comes in and go from there. Thank you for all the help!

 

[jpdevol]

Good deal; if questions arise, post back please