Reg/Rec and Generator fault diagnosis (and battery test)---

[MaXX2]

The generator produces electricity (of the AC type- the same as is in your house) to recharge the battery on your bike and run the engine and electrical system when you’re on the move. The Regulator/Rectifier (Reg/Rec) takes the AC power from the generator coils and 1) Rectifies it to DC current which can be used by the bikes electrical components and; 2) Regulates it to a the right voltage.

If the bike isn’t charging properly or if strange things are happening with the electrics (blown bulbs and fuses all of a sudden, unexpected flat battery etc etc). Try these tests in order BEFORE riding the bike if at all possible. The first test, checks the generator coils and the second, short test, checks the reg/rec. Treat the whole thing as a set routine. You only need a multimeter and an assistant and it’s easy, only taking a couple of minutes once you’ve got the seat and tail fairing off—

TEST 1- GENERATOR COILS

Locate and unplug the reg/rec. The carb models have one plug- the FI's have 2 plugs.

Set your multimeter to 200v AC range (AC is not the norm with 12V systems, but it is what you need for this test)

Looking at the reg/rec plug and you will see three yellow wires (for the sake of calling them something- A, B & C will do nicely) there’s no visible difference between them and don’t worry about that.

Start the bike and get someone to hold the revs at around 3000 rpm. With the engine running at that speed- test the voltage across wire A & B and write down the reading, the do the same across wires A & C and lastly, wires B & C. All three voltages you have written down should be similar (say within 1 or 2 Volts of each other) and all should read around 24-27V for carb'd machines or 40-60V for FI machines.

If one of the voltages is outside the above parameters, or the voltages are considerably outside the 24-27V (carb) or 40-60V (FI) range then the generator coils have failed and will have to be replaced.

If the voltages are all within the parameters above, then the reg/rec has failed and will have to be replaced.

TEST 2- REGULATOR/RECTIFIER

It’s possible that if the reg/rec has failed, it has taken the generator coils with it. If it has, replace the generator coils first and when they’re replaced, set the multimeter to the 20V DC setting and put the test probes across the battery terminals (Red to live, Black to earth). Start the engine. Initially, with the starter motor turning the crank there will be a drop in voltage (expect 10.5-11V), but when the engine catches, you should see the voltage reading rise immediately and continue to rise and fall when the engine is gently revved and released.

If the voltage doesn’t move or if the reading drops slightly- CUT THE ENGINE immediately and order a new reg/rec, because the original has failed. Don’t run the engine a second longer than you have to and bearing in mind the test reveals results immediately the engine fires up, it should be less than 10 seconds.

Finally, and assuming the voltage is flowing as expected, flick the headlight and main beam on and rev to 5000 RPM. In a perfect world, you'll see figures in the mid 14's Volts. As a personal comment, my first 'bird ('96 build carb) ran at 14.9 Volts and it didn't bother the reg/rec or anything else throughout the life of the bike.

And that’s it- how to check for failed generator coils and reg/rec in a nutshell.

TEST 3- BATTERY

Well... Look, you're standing there with the seat off and the multimeter to hand, so you might as well check the battery voltages (static and deep). If you do this, you've checked and cleared the entire charging system. Before doing this however, let me say that these tests are simple and basic. I haven't accounted for testing in extreme temperatures (which can make a difference to readings) so if you're doing this in winter at zero degrees let me know and I'll try find the appropriate figures for you.

First test, is the static charge or to put it another way, what voltage your battery is holding at the time of the test itself. First make sure the battery is fully charged then set the multimeter to 20V DC and place the probes across the battery terminals (red-pos and black -neg). In a healthy battery the reading should be over 12.7V.

Second test is a load test. This is a tad fiddly, but well worth it because test 1 alone means very little. What you really need to know is what your battery can push out and for how long. So the test...

1. Again with battery fully charged, disconnect the ignition. On carb models remove the earth or live wire from each of the coils and on FI models, removing the ECU fuse should do it (I think, because I don't own one). The purpose is to be able to spin the engine on the starter button, without the engine firing up.

2. With the ignition disabled, turn on the ignition switch and turn the headlight on for three minutes. This will scrub off what's known as surface charge.

3. After three minutes, set the multimeter to 20V DC and place the probes across the terminals as with test 1 above. Then push the start button 30 seconds whilst closely watching the multimeter reading. The voltage should not drop below 9.6V at any time throughout the 30 seconds. A good, strong healthy battery won't drop below 10.5V during that test, so between those values and you're on the money.

It might be worth mentioning that specific battery load testers can be bought. Instead of disabling the ignition, the device has a resistor built in, that simulates the load required to stress the battery. All you do is connect the device across the terminals and look at the read-out. Not tempted meself, but worth a mention in passing.

Anecdotally (but worth a mention anyway) about batteries- I recently blew my reg/rec on a run out. The consistent power surge involved evaporated most if not all of the electrolyte away. Static testing of the battery produced a reading of 12.4V. Load testing was zero, barely enough to keep the dash clock running on time.

Hope it helps

Mick

[patch]

will do ththese tests for my flat battery problem many thanx

[MaXX2]

My pleasure, glad it helped Patch. Even if it shows up no probs other than a worn out battery, your mind's put to rest.

[patch]

hi did the test as u said found reduced voltage on gen windings a b took off fairing and alternator cover and could see damage to part of windings now in process of ordering new stator think ill replace regulator as well just to b certain thanks again

[MaXX2]

hi did the test as u said found reduced voltage on gen windings a b took off fairing and alternator cover and could see damage to part of windings now in process of ordering new stator think ill replace regulator as well just to b certain thanks again

If you buy the parts from Jaws Patch, they're uprated. Up to you whether you replace the reg/rec as well, but it's handy to pack a spare anyway. I usually do if I'm heading away on holiday.

[patch]

i have fitted new stator and now regulated voltage is perfect i had already ordered part but will remember jaws parts in future have now posted problem with heated grip any experience with

[MaXX2]

i have fitted new stator and now regulated voltage is perfect i had already ordered part but will remember jaws parts in future have now posted problem with heated grip any experience with

Gives a chap a buzz when things work out well dunnit eh

[Tigger]

Ty Dr.Facto

[MaXX2]

Ty Dr.Facto

I have NO idea what this means Tiggs BUT... if it's nice cheers and if it's nasty... bollox

[jonabonospen]

T.......... all should be around 24-27V.

If one of the voltages is outside the above parameters, or the voltages are considerably below the 24-27V range then the generator coils have failed and will have to be replaced.

If the voltages are all within the parameters above, then the reg/rec has failed and will have to be replaced.

What should the readings be if the reg/rec is fine? Or should the sentence read that if they are all outside the parameters shown then the reg/rec has failed and needs replacing?

[MaXX2]

It's not important. I think you might be getting confused between testing the genny coils and testing the reg/rec. The genny test (as you've qouted above) samples the power from the genny coils direct, ie before it even gets to the reg/rec.

To test the reg/rec do it as I set it out at the 'TEST 2 REGULATOR/RECTIFIER' section of the write-up.

PS don't forget to set the multimeter to AC power to test the genny side and DC to test the reg/rec.

[jonabonospen]

I see. Will give it a bash at some point over the next couple of weeks then when I get a chance.

[Tigger]

Ty Dr.Facto

I have NO idea what this means Tiggs BUT... if it's nice cheers and if it's nasty... bollox

It's tigger for .... drifted off at AC

[MaXX2]

Ty Dr.Facto

I have NO idea what this means Tiggs BUT... if it's nice cheers and if it's nasty... bollox

It's tigger for .... drifted off at AC

Good lad...... dozing off there might just have saved yer life

[XXtremist]

Hi Mick,

Been having intermittant starting probs, as though battery was flat. On Tim's advice, cleaned the contact on the actual start switch and thought that had cured it, but it has not.

I did the stator test, and all three readings across the yellow wires are 40 V, way above the 24-7 range. There is no resistance continuity between any of the yellows and earth though.

Doing the reg/rec test ( with the headlight on, as it says in the manual ) voltage climbs to 14.47 V DC up to 2000 revs, then falls away back to battery voltage of 12.83 V above those revs. Incidentally, voltage does continue to climb to 17 V without the headlight on.

Would you suggest changing the stator? Thats an oil out job I suppose. ( Only recently changed it )

Regards,

Chris

[MaXX2]

Hi Chris-- sorry for the delay, work I'm afraid. I'll have a go at the problem in bits---

Hi Mick,

Been having intermittant starting probs, as though battery was flat. On Tim's advice, cleaned the contact on the actual start switch and thought that had cured it, but it has not.

For starting problems, have a good look at the starter relay first. It's the rubbery, boxy thing attached to the +terminal on the battery, with a 30amp fuse on it and two heavy cables. Check the cable connections (they're on with good solid 10mm nuts if I remember right) and ensure that they're properly cleaned, greased, tightened and tidy. I have a starter relay spare here if you want to give it a try. I'll check it's right for your FI model before sending it off

Run a load test on the battery. Make sure the batt is fully charged. Connect the voltmeter across the batt terminals (voltage should be 12.6-12.9ish) and crank the engine on the start button for 10 or 15 seconds. The voltage will obviously drop under such a load for such a period, but it shouldn't dip under 9.5 volts. If it does the batt is weak.

I did the stator test, and all three readings across the yellow wires are 40 V, way above the 24-7 range. There is no resistance continuity between any of the yellows and earth though.

I've no books in front of me so don't know for sure, but 40V sounds like a lot more than I'd expect from the genny coils. I would suggest giving Jaws (or anyone who knows what the output of a healthy FI stator should be) a ring. It may not be a problem at all as long as the reg/rec can cope with that input constantly.

Doing the reg/rec test ( with the headlight on, as it says in the manual ) voltage climbs to 14.47 V DC up to 2000 revs, then falls away back to battery voltage of 12.83 V above those revs. Incidentally, voltage does continue to climb to 17 V without the headlight on.

With the lights on and the revs above say 2000 and above, the reg/rec should provide voltage that varies but in the 14's, to run the electrics and recharge back to the battery. The reg/rec does sound faulty to me, on the grounds that it shouldn't drop to 12's when the lights go on. I would also, as a matter of course, check earths around the bike as well. That kind of V dip sounds 'earthy' if nothing else

Would you suggest changing the stator? Thats an oil out job I suppose. ( Only recently changed it )

At the moment Chris, no. I'd certainly speak to John (or whoever) first to find out about the stator output, before coughing up for parts.

Regards,

Chris

Hope it helps mate and I hope it's not as irksome as it sounds

Mick

[XXtremist]

Thank you Mick for that very comprehensive reply.

I did some further research on the US site and came across a flow chart for analysing problems with the battery/ generator/ reg-rec. There they gave the AC voltage range from the yellows ( or white as they are in the States ) from 40 to 60 V. Don't know for certain, but perhaps that is the result of an uprated genny for the FI over the carb model.

So I decided to order a new reg/rec from Jaws. With a fair wind it should be here tomorrow. Will make a further report when I have fitted it.

Sorry my original enquiry was not as methodical as your reply. I had also checked the starter relay after cleaning the starter switch contacts. Thanks for the offer of a replacement, but let's see how things are after the new reg/rec.

Cheers

Chris

[T.Murphy aka Tim]

Chris, re the stator. Just for info in the future it is not an oil out job. When you take the Alternator cover ( "genny" is such a twee word aint it) off you'll only lose a small amount of residual oil from the housing itself. ( with bike on centre stand of course). Nowt worth worrying about.

[Tazcbr1100xx]

Chris, re the stator. Just for info in the future it is not an oil out job. When you take the Alternator cover ( "genny" is such a twee word aint it) off you'll only lose a small amount of residual oil from the housing itself. ( with bike on centre stand of course). Nowt worth worrying about.

Failing that, you could always lay it on its side so that the oil drains away from the AlterGenny cover

[XXtremist]

UPDATE: Success

Fitted the new Jaws reg/rec unit and all works perfectly now. With the lights on, getting a steady 14.1 to 14.2 V up through the revs.

Because the new unit had longer cables to the connectors, I was able to mount it further back on the sub frame, where I remember it was situated on my previous 05 bird (but on t'other side). Using two flat brackets with bolts on the inside of the frame, it now sits above the handle ( inside the seat cowl ) where there is an opening for your hand. So in theory, it should get more air for heat dissipation.

Position of old reg/rec

Position of new unit further back

Thanks to all who contributed.

Chris

[Tazcbr1100xx]

it now sits above the handle ( inside the seat cowl ) where there is an opening for your hand. So in theory, it should get more air for heat dissipation

Try twisting the throttle a bit more - that will help heat dissipation

[aj]

Try twisting the throttle a bit more - that will help heat dissipation

... you change your regrec quite often then...


regards
aj

[Tazcbr1100xx]

Try twisting the throttle a bit more - that will help heat dissipation

... you change your regrec quite often then...


regards
aj

Yes - the is coming up to 10 years old so it must be getting ready for changing sometime over the next 10 years or so

[Tazcbr1100xx]

Yes - the is coming up to 10 years old so it must be getting ready for changing sometime over the next 10 years or so

.................... and a week later, it died - RIP Superior Sexy Silver XX

Next time I'll keep my gob shut

[Mister Majestik]

Taz
are you all sorted, up and running now?