New ROTOR installed, few questions

Skull,i just realized your from Down Under Mate. I didn't think it got cold there!. Good info.
In Canada ,probably around late 70,s all cars and probably bikes ect had to have daytime running lights
and all the manufacturers implemented this in there products. I think 77 may have been a change over year
and Yamaha (in canada) made the 77 with the on/off switch but wired it so it would come on regardless when u started the bike.
I think its a great idea to be seen easier during the day but with the poor electrical and starting system on this bike it certainly
didn't help matters when having enough to get that bike to fire.
 
Looking at the windings of XS650D's broken rotor pics.
I think I see a thick, white plastic winding bobbin.
And, looks like finer wire than what Jim is using.

Thinkin' out loud here,

That bobbin would take up precious space, requiring smaller gauge wire, and possibly fewer windings, to meet the 5 ohm spec. Resulting in less magnetism, requiring more current, and lower tolerance of heat.
 
Thinkin' out loud here,

That bobbin would take up precious space, requiring smaller gauge wire, and possibly fewer windings, to meet the 5 ohm spec. Resulting in less magnetism, requiring more current, and lower tolerance of heat.
Agreed. With 22ga wire (the size Yamaha used), I can barely squeeze in the required windings to get to 5 ohms. Wouldn't surprise me if they were using 24ga. wire. I'm thinking that would make it less vibration tolerant also.
 
Skull,i just realized your from Down Under Mate. I didn't think it got cold there!. Good info.
In Canada ,probably around late 70,s all cars and probably bikes ect had to have daytime running lights
and all the manufacturers implemented this in there products. I think 77 may have been a change over year
and Yamaha (in canada) made the 77 with the on/off switch but wired it so it would come on regardless when u started the bike.
I think its a great idea to be seen easier during the day but with the poor electrical and starting system on this bike it certainly
didn't help matters when having enough to get that bike to fire.

Where i am now, no it doesn't get cold........yes it does i'm acclimatized...........I am referring to when i was in NZ. Bought it in 1990, Still have it and it's still going for when i go back.
 
His bike is a 77.... pre TCI. My rotor works for his bike. The aftermarkets all come with the TCI magnet so they'll work for all years.... it's just not needed for his 77D
Hey Jim, wish I had read this post first, mine went a couple of days ago! Ordered one from mikes,glad I stayed away from ricks now! Can you give me any feedback on the one for mikes! And do you make ones for tci, I have a 81 special,and how do I go about ordering one from you? Thanks for the great info on rotors!
 
Two Many, that white plastic or probably EPOXY weld had literally broken away from the
rotor probably caused from either vibration and or heat BUTmost likely its just poor quality Epoxy and or job
of applying it. My pics not very clear .The first unit I couldn't see anything wrong that jumped out at me so
the wire may have broken internally not sure.I am somewhat concerned that ive had this much bad luck with these
and my original that im curious if something else is causing them to break prematurely.Before installing a 4th unit from Jim.
Is there anything I should test to ensure success. Im not electrical savvy so if u could be specific as to the wires and voltages ect.
I usually just test the rotor before (see how may ohms) then install and check bike runnin on battery to see if its charging and at
what voltage usually looking for 14.3 to 14.5 nothing higher.My battery has been tested good.I have an updated Reg vr115 and Mikes xs


Rec. I will check them for loose connections,install new brushes ect.Could the Rec not working properly cause issues to a Rotor.I realize
its job is to change current from AC TO DC I believe and the Reg regulates the current to keep it at a set voltage to charge but not over or under charge.I think these are the only pieces of the puzzle I should be looking at.None of my lights have burnt out or are acting weird.
My ground wire is like new ,clean and tight to battery. I guess im shell shocked from the 3 in a row! What about the Stator,its original!
Can a bad Stator damage a Rotor?

FYI,there is apparently 2 Ricks out there selling these, not sure if same product.Mine were Ricks Motorsports.Ive heard nightmares on Mikes xs stuff.Im not out to hang anyone just stating my personal experience with the products.They may have had a bad batch or run.
 
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Hey Jim, wish I had read this post first, mine went a couple of days ago! Ordered one from mikes,glad I stayed away from ricks now! Can you give me any feedback on the one for mikes! And do you make ones for tci, I have a 81 special,and how do I go about ordering one from you? Thanks for the great info on rotors!
I have no experience with Mikes rotor... however, I suspect they all come off the same factory floor in China. One problem I'm aware of with them is the classic "weak TCI magnet syndrome." But... the problem isn't really a weak magnet. The copper slip rings are too thin to block the rotors magnetism and it screws up the TCI operation. Maybe @delagem can chime in here. He fixed his TCI problem with one of my rewinds.
If you want to order one, read the info in my ad.... then PM me.
EDIT: Oops... forgot the link. It's there now. :whistle:
 
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Two Many, that white plastic or probably EPOXY weld had literally broken away from the
rotor probably caused from either vibration and or heat BUTmost likely its just poor quality Epoxy and or job
of applying it. My pics not very clear .The first unit I couldn't see anything wrong that jumped out at me so
the wire may have broken internally not sure.I am somewhat concerned that ive had this much bad luck with these
and my original that im curious if something else is causing them to break prematurely.Before installing a 4th unit from Jim.
Is there anything I should test to ensure success. Im not electrical savvy so if u could be specific as to the wires and voltages ect.
I usually just test the rotor before (see how may ohms) then install and check bike runnin on battery to see if its charging and at
what voltage usually looking for 14.3 to 14.5 nothing higher.My battery has been tested good.I have an updated Reg vr115 and Mikes xs


Rec. I will check them for loose connections,install new brushes ect.Could the Rec not working properly cause issues to a Rotor.I realize
its job is to change current from AC TO DC I believe and the Reg regulates the current to keep it at a set voltage to charge but not over or under charge.I think these are the only pieces of the puzzle I should be looking at.None of my lights have burnt out or are acting weird.
My ground wire is like new ,clean and tight to battery. I guess im shell shocked from the 3 in a row! What about the Stator,its original!
Can a bad Stator damage a Rotor?

FYI,there is apparently 2 Ricks out there selling these, not sure if same product.Mine were Ricks Motorsports.Ive heard nightmares on Mikes xs stuff.Im not out to hang anyone just stating my personal experience with the products.They may have had a bad batch or run.

Dunno if my recent experience would help you any, but might be worth a look. I was getting quite a key-on, motor-off voltage drop between fully charged battery and brown wire brush terminal at rotor, over 1 1/2 VDC. I pulled the connector for the key switch apart and found all three blades (red, brown and blue) all crapped up. Removed all three blades from the male half, cleaned them thoroughly to bright brass, put on a little contact grease and re-connected - reduced the previously measured voltage loss by over 1 volt. Dunno how I missed cleaning that connector over the years I've had the bike; it's a pretty important one to maximize voltage on the brown circuit and thus minimize charging demand.
 
I just read an old post from Pamcopete stating the if Rectifier not working correctly it can damage the Rotor!
I think I will have a go at testing all the wires to and from it. Question I have is I currently dont have a rotor that
works, (I have my defective original) do I need to have a rotor working or not in the bike to test the Rectifier properly.
The bike will start just no charge. I think some of the Rec tests state the motor to be running. The 3 white wires coming from the
Stator ect,yellow wire? Thx for any guidance with this.

Thx Aldo.my key switch is brand new last season plus I sanded all the contacts were it connects at that time but anythings possible I guess
 
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XS650D, Your right on the rectifier just changes AC to DC.
Not exactly right on the Regulator. The regulator reads the voltage on the brown wire. It then controls the current flow through the rotor by turning the current flow on and off. \When you first turn the bike on the brown wire voltage is around 12 to 13 volts. The reg reads this and sends full current through the rotor. Once you start the engine and the alternator starts making electricity, At idle the alternator doesn't make much power. Your brown wire voltage won't be much more than before you started the engine. As you rev the engine the alternator out put rises. Around 2000 to 2500 RPM's the brown wires reaches the regs preset voltage of about 14.5 volts. At this point the reg turns off the current flow through the rotor. The voltage drops to below the pr4eset 14.5 volts and the reg turns on the power flow. This on/off repeats as needed to maintain the brown wire at the 14.5 volts.
The old mechanical regulator are limited in how fast they cycle. Maybe hundreds of time per second. The solid state regulators have almost no limit to speed and can cycle thousands of time per second.
When the voltage is low, the on part of the cycle is longer than the off part of the cycle. Once the battery is fully charged the on time is less and the off time more. This helps keep the rotor from over heating.
A weak battery that needs more charging keeps the on part of the cycle on longer. if weak enough it can keep the rotor running at max all the time. This overheats the rotor.
Poor connections from the battery to the regulator can do the same thing by keeping the regulator reading low voltage even if the battery is fully charged. This is why having very low voltage drops at the connections is important.
In the charging guide there are methods to bypass the regulator to check if your no charge issue is I the regulator or rotor/stator.
When bypassed you should gets a significant increase in the voltage. It can go to well above 15 volts. If your bypass test shows this the regulator is not functioning. This can be from several issues. one is a bad regulator. another is bad ground on the regulator.
When checking anything electrical you should always check the grounds.
Leo
 
Thx XSLeo, no mention of the Rec causing issues ? Could that be a potential issue also?
Also this brown wire u state to check, were exactly is this brown wire, at the stator or brushes
or at the Regulator?
 
On the rotor and stator OHM checks you don't need the engine running. The running checks are for AC voltage coming out of the stator.
Do the OHM checks first. The rotor is from slip ring to slip rung and should read 4.5 to 5 ohms. Check from slip rings to ground. Should read infinity. This checks for shorts to ground.
The stator is from white wire to white wire. and should read about .9 to 1 ohm. I do this where the stator plugs into the harness. Think in your head and number the white a wires 1, 2 and 3. Check 1-2, 1-3, 2-3. The readings should be all the same.
These white wires hook into three sets of windings with a central connection point. These white wires check two sets of these windings at a time.
You can also check the ohm's on the yellow wire. This yellow wire hooks to the central connection point mentioned above.
To check ohm's this way check from the yellow wire to each white wire. This checks just one sets of windings at a time. So the ohm's will be about half what you get with the white to white checks. About .45 to.5 ohm's.
You also need the check from the wires to the body of the stator. It should read infinity. This checks for shorts to ground.
In the manuals they list the .9 spec on the earlier bikes then around 80 or so, don't recall just when, they started listing a .45 ohm. I think this was because they changed the way they tested, not that the stator changed.
Once you get the OHM checks, and the wiring checks done and have it running. You can check the AC voltage on the white wires. With every thing hooked up back probe the white wires at the plug. Again the 1,2,3 thing. Should gets at least 10 volts AC on all threes sets. If you do a reg bypass when checking the AC you can get a reading in excess of 15 volts AC. The yellow wire should get a voltage of above 4.5 volts. Your meter may read it as AC but is more of a pulsing DC. Try both AC and DC on the meter. The safety/headlight relay trips at about 4.5 volts.
I wouldn't worry to much about this test if all your ohm checks tested good and your reg bypass says your rotor/stator are working.
On most everything electrical on these bikes the readings can vary from spec by around 10%.
Leo
 
no mention of the Rec causing issues ? Could that be a potential issue also?
Absolutely. The rectifier takes the 3 phases of A/C from the stator and runs it through a 6 diode bridge network.... allowing only the positive half of the A/C voltage through. If one of those diode opens, your gonna lose half of that phase. If it shorts, you'll lose the whole phase or... 1/3 of the alternators output. If it's an old wore out one, with high resistance on some of the connections, you'll lose power across it too. Any loss of power across the rec. will result in the regulator trying to make up the difference by working the rotor harder (on for longer duration's). Remember... heat is the killer.
 
Let me rephrase that statement above....

Any loss of power/voltage across the rec. just about anywhere in the charging system will result in the regulator trying to make up the difference by working the rotor harder (on for longer duration's). Remember... heat is the killer.

Rotor's on the way. I'll PM you the tracking...
 
Let's start at the battery. A red wire goes to the main fuse, then to the key switch. The switch sends out power on the blue or blue/black wire to light the tail light and on some bikes the dash lights.
It also sends power out on a brown wire to the fuses. Between the switch and fuses the brown wire tee's off to send power to the regulator. You need to check voltage drops at every connection along this pathway.
On the later bikes that uses the combo reg/rec the brown wire also feeds the rotor. So on these bikes check for drops along that wire too.
If you cleaned your key switch then you got the worst of problem doing that. This one is the worst offender because it is always making and breaking connections. The rest of the connections remain connected most of the time but stuff from outside the connection can get in to contaminate and corrode the connection. This is why they need to be cleaned and a bit of dielectric grease applied. This grease help keep crud out and prevents the contacts points from corrosion.
Starting at one end of the bike and working to the other cleaning, tightening and greasing every connection on the bike helps prevent a lot of electrical issues before they become issues is time well spent.
Leo
 
Thx Guys,lots to check!
Will wait till I get the new rotor to test everything hooked up ,so I can run the bike for some of the tests.
Thx Greatly
Warren
 
XSLeo, want to confirm some of your advise if I understand correctly , The white connector plug under the tank were the 3 white wires
and 1 yellow wire are located. Test there for ohms .9 to 1 ohm (not running) on the 3 sets of white wires. Then retest same wires (engine running) for Minimum AC Voltage of 10 Volts ,have I got that correct ? That white plastic plug connector stays connected for all Ohm and AC tests?
 
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Jim,will one of the test procedures XSLeo gave alert me to a bad Rectifier or is there a special way to test
the Rec. I have the one from Mikes xs Thx. Ps: I installed it few years ago and no issues for 10,000 miles BUT!
 
Jim,will one of the test procedures XSLeo gave alert me to a bad Rectifier or is there a special way to test
the Rec. I have the one from Mikes xs Thx. Ps: I installed it few years ago and no issues for 10,000 miles BUT!
I believe Leo was having you test the stator. The best way to test a rectifier is by using a meter with the diode test function. You want to see about a half a volt or less voltage drop across each diode in one direction (fwd bias). Reverse the leads and you shouldn't see any voltage. Your manual should have a table for the test.

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