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Tmax 500 2008- charging voltage ?

16K views 65 replies 2 participants last post by  pellicle 
#1 ·
I have a tmax 500 2008, which is the correct charging voltage?

mine is 13.7v at 1300rpm and 13.9-14 at 3-4000 rpm
if starting the long beam drops to 13.2 and at 4000 13.5 maximum.. is normal?
 
#3 ·
When the fan starts the voltage is very low, and when short trip, the full charge does not hapend, new battery every year

I checked the resistance to the stator, it is in specifications, ok wiring, new relay 2pcs
After a longer journey do not charge only 13.7 with all consumers stopped
If i remov the bulb from the short beam, then charge is 14.2 max
 
#10 ·
Smiley32 said:
Yes without headlight is 14.20v in 1300 rpm
just double checked mine

14.02 by 2500rpm
max reached of 14.05 by 4500 rpm

you've double checked earths are good and that battery is in good order (and its an AGM battery too right)?

and by check I mean physically look at where it bolts onto the chasis, unbolt it, clean it (perhaps wire brush) and replace it with a smear of vasaline over it first.
 
#11 ·
Yes i check the stator connector( white 3 pole)
I check the ground on the wiring installation ( i have 2 ground points, one is for the ABS)
Not check the ground on motor, I need a lot of work to get him
But I think if it were the problem would not turn the starter

Maybe the ABS module consumes some current

Ps: how much charge with the hight beam on?

Battery AGM
 
#12 ·
Smiley32 said:
Maybe the ABS module consumes some current
its possible ... but as I discovered
Ps: how much charge with the hight beam on?
its a brief transient drop then back to exactly the same number. I would expect that the stator is designed to provide more current than is needed (it has accessories for heated grips right?) and so as long as you aren't running a high wattage headlight that it'll be able to cope.

I suspect that (as you've changed the regulator) there may be a coil burn out brewing. Have you tested the OHMs between ground and each of those 3 white wires (or just continuity)? Perhaps with the engine hot? Although I assume you've measured charging voltage both hot and cold right?
 
#13 ·
Smiley32 said:
Maybe the ABS module consumes some current
its possible ... but as I discovered when answering this:

Ps: how much charge with the hight beam on?
its a brief transient drop then back to exactly the same number. I would expect that the stator is designed to provide more current than is needed (it has accessories for heated grips right?) and so as long as you aren't running a high wattage headlight that it'll be able to cope.

I suspect that (as you've changed the regulator) there may be a coil burn out brewing. Have you tested the OHMs between ground and each of those 3 white wires (or just continuity)? Perhaps with the engine hot? Although I assume you've measured charging voltage both hot and cold right?

Have you measured the amount of current drawn from the battery with the ignition ON but motor not running? There will be an initial draw as the fuel pump starts, but with it on centerstand and side stand up it should not be much. You'll need to have a 10A capable multimeter and measure that with the meter in series (bridging) the +ve terminal and the battery (meaning : no meter = no circuit)

Make sure you select 10A and put in plugs correctly AND re configure the meter when you return to Volts (or poof, there goes a fuse in your meter or worse)
 
#14 ·
Thanks for the reply!

The curent is 0.01 A
I have some video with the charging voltage



When i tested the OHMs between ground and each of those 3 fase no read on multimeter
The stator resistance was very close to the specifications in the manual, I do not remember the exact temperature
I check the ouput voltage in all three phases is 26v AC all tree
 
#15 ·
Smiley32 said:
Thanks for the reply!
welcome

The curent is 0.01 A
wow .. really? Man that's efficient (I'd have thought that the compartment light would draw more, but perhaps your battery is in a different spot)

When i tested the OHMs between ground and each of those 3 fase no read on multimeter
interesting ... which because they put out milliamps in measuring that it could be that one of the coils is perhaps close to breaking through but not sufficiently to push across that ...

perplexing

everything else looks right
 
#16 · (Edited by Moderator)
Ok
allow me to describe the test first and the theory second

* get a test lamp / probe that has a small bulb in it.
* connect the clip to the +ve terminal
* touch the probe end to each of the white wires (probably up at the regulator plug will be easiest)

the bulb should stay dark.

But if there was the beginnings of a breakdown in the insulation surrounding the coils in the stator then the multimeter may not pick that up. The insulation around the coil should be sufficient to not allow a break through from ground.

Assuming it passes this test, then one needs to again look very carefully at the ohms readings from each of the stator phases. Its possible that a short exists between two of the three coil phases, shortening their length and reducing the potential voltage.

The stator is wired like this

statorShort.jpg

but has a few more nodes as seen on my stator when I pulled it out:


and so a short circuit as I've indicated in RED may be at work.

How accurately did you measure the AC voltages?

Smiley32 said:
Thanks for the reply!
I check the ouput voltage in all three phases is 26v AC all tree
also the question I was asking about temperature was not a "room temperature" question, but a "was the bike at operating temperature or just started cold and ran for a minute or so" temperature question

let me know if either of my thoughts are on the money

:)
 

Attachments

#18 ·
Smiley32 said:
Why the manual say to put the multimeter on AC 20v to test
I don't know, but I didn't measure my AC voltages in my diagnosis.

(I assume you read my blog post on that in case not:
http://cjeastwd.blogspot.com/2012/09/my ... tator.html
http://cjeastwd.blogspot.com/2012/10/t- ... tails.html )

Linked was this page http://www.jetav8r.com/Vision/Stator/Stator.html

A significant point mentioned in that is:
The stator A.C. output voltage varies with engine RPM. The more RPM the more voltage. So, the stator output must be "Regulated" to provide 12-15 volts into the bike system. The raw A.C. output from each circuit is about 50volts ac at medium RPM

So I suggest that you get an assistant (or clamp probes) and look CAREFULLY at exactly the V at different RPM (you need to take a measurement (arbitrarily calling each red wire A B and C)
*A-B
*A-C
*B-C
to measure all coils in their full length.

(edit) Indeed re-reading that link I gave above it says:
* Output after regulator box should be 14.5 volts DC engine running no load
* Each stator wire should have continuity with the others (0.32 ohms by the book).
* No stator wire should have continuity with ground (short or bad insulation)
* Engine running, each set of stator wires (1-2,2-3,1-3) should produce 50v AC.

If any coils is shorted to another you will see perhaps only a few V difference, so its important to write it down or speak it out during your phone recording AND the RPM ... be structured ... 2000 RPM then 3000, 4000 and then 5000

I still think that the test lamp to check for any insulation bleed between the coils is a good test for any potential leak to ground, however it won't show that up between coils. I would caution putting 12V DC across each of the stator windings (the three white wire phases) because it won't actually help.

Given your charging situation sounds almost identical to mine and mine was a stator in the end I'm leaning towards that being the solution. I did the work myself but the part was about AU$500.

hope to read your results soon

Best Wishes

(and a PS about me. I'm actually an electronics engineer who began in electronics as a technician, so I have some diagnostic abilities even if I spent 90% of my time around micro-processors)
 
#19 ·
Ok, but in that post is the old model-2007 the stator has another part number, the rectifier is another model, even stator resistance is different according to the manual ( 2008- 0,225-0,275 and old -2007 0,220-0,260) I do not know if it is important

I will check all the details when I get to the scooter and post it, all the values ​​exactly!

Thanks!
 
#20 ·
Smiley32 said:
Ok, but in that post is the old model-2007 the stator has another part number, the rectifier is another model, even stator resistance is different according to the manual ( 2008- 0,225-0,275 and old -2007 0,220-0,260) I do not know if it is important
really, those numbers are insignificant in variance ... think about it:
Min .225 or .220
Max .275 or .260

mine says .216 ~ .264

The reistance is only a reflection of the copper wire length (and grade) as not all stators will be made identical (or even in the same factory by the same person) and also those values will vary with temperature (meaning hot engine vs cold engine) because that's one of the properties of conductors.

I will check all the details when I get to the scooter and post it, all the values exactly!
That will be the next step...
 
#22 ·
Smiley32 said:
Hi, new update
ok, so this confirms the charging voltage ... however I was unable to read the tacho (and holding the phone vertically destroys the image quality. Youtube like your TV or the Cinema is not vertical it is horizontal).

what was the tacho RPM?
I don't understand what this means, but is this OHM readings of the phases? (which are 120 degrees apart)

there is no short with light control
this part I think I'm clear on, it means that with the battery +ve terminal at one end of the test lamp there was no light found on any of the phases... yes? That's a good thing for your Stator ... however we still don't have a solution

What is the Watt rating of the main headlight bulb?
 
#24 ·
Smiley32 said:
"What was tevh RPM? " No rpm, is the ohm masured on stator pin 1-2-3 white
in that video there was clearly a voltage being shown, and the bike operating (thus the meter nearly slid off) the bike (bluetac). I could see the scale rise, but not read what the RPM was. Not that it matters much because it should be charging.

Is it possible to read the AC levels across the white wires (a test I mentioned earlier). This will reveal if there is an internal short in a coil which is reducing the maximum power of the coil output.

You measure by putting the probe on (lets call arbitarially each white wire A B and C) A-B, then A-C and then B-C

I recommend some gaffa tape applied to the throttle to keep the RPM at about 3000 while doing this (giving you a free hand if you don't have an assistant).
 
#26 ·
Smiley32 said:
Hi, new updates..

From all 3 white pin same voltage 20v on idle 80v on 5000rpm
weird ... so more or less within a few volts right? I was wanting to rule out a short within a coil and thus giving less turns in that coil and thus less volts on a phase ... such a fault would not be clear in an ohms test on the coil.

And a voltage with radiator fan on
its interesting that the charging is just a few fractions of a volt low ... and you've changed the regulator with a genuine Yamaha one? And the battery, is definately the AGM type right? (not a sealed flooded lead acid nor a gel cell ... right?)

https://batteryuniversity.com/learn/art ... ss_mat_agm

(just in case it was not sold by Yamaha ...)

I'll re-read this thread fully again later, but I'm about to step out for the rest of the weekend (and wanted to let you know it'd been read)
 
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