[bochnak]

Bought a brand new battery yesterday, and at idle, the voltage is 13.0-13.2V across the terminals. Reving the bike up past 3k did not increase voltage. The was done with headlight and taillight off. It was late last night and the bike is pretty loud, so I did not do any further testing.

I disconnected the alternator leads from the rectifier and hooked it up to a 1156 or 1157 taillight bulb. At idle the bulb almost blinded me, so from what I have read, it's safe to assume the rotor/stator is good.

So basically, I have replaced the battery, cleaned connections at rectifier and earth.

Should I be questioning the rectifier next? Seems like I can get one from radio shack.

Thanks,
Matt

 

[sandergecko]

With a full battery like that the voltage might not increase, because it's full.
Switch your light on for a while to get it around 12 v then test again. Voltage should be around 14V when you rev.

 

[bochnak]

With a full battery like that the voltage might not increase, because it's full.
Switch your light on for a while to get it around 12 v then test again. Voltage should be around 14V when you rev.

Good point. I'll try that.

 

[Tony the torch]

turn the lights on without the engine running and let the battery run down for a while until the lights start to get a bit dim, then start up the engine and rev it and see if the lights get brighter. if the do you're alright.

 

[bochnak]

Thanks guys.

Should I look for any specific voltage level at idle and 3k?

 

[Tony the torch]

all I do is turn the headlight towards a wall and see if it gets brighter when you rev it up.

 

[bochnak]

Update:

At idle, with lights on, battery voltage drops to the high 11's. When revved up, I see maybe an increase of 0.5V. If I turn lights off, voltage is in the low 12's, and barely reaches 13V when revved.

I swapped out the rectifier for one from Radio shack with no improvement.

I disconnected the zener diode lead while bike was idling with no change.

Anything else I should check? Connections are clean and tight. I re-wired some questionable connections.

I am going to get a 1 ohm resistor and AC meter today. Should I try a higher wattage bulb, say 60-100W?

Thanks.

 

[Loffer]

Sounds like the stator/ rotor. The rectifier just converts the voltage. Prbobly need a new rotor.

 

[Loffer]

Sounds like the stator/ rotor. The rectifier just converts the voltage.

 

[flypa38]

Also look at where the wires enter the stator and where they cross over the primary chain. There's a tight bend where the wires enter the stator. A loose primary chain can eat through the wires where they cross over too. Won't cost anything to look!

 

[bochnak]

Also look at where the wires enter the stator and where they cross over the primary chain. There's a tight bend where the wires enter the stator. A loose primary chain can eat through the wires where they cross over too. Won't cost anything to look!

Wires in that area are good. I have the primary cover off right now, just set the timing.

 

[flypa38]

Check out the rotor for sure then! I think I read somewhere it should be able to hold a 5lb. weight.......my old rotor would barely hold a finishing nail!

 

[bochnak]

Did some testing after dinner:

Resistance between 2 stator leads @ rectifier is 0.5 ohms. Each lead has infinite resistance to earth.

With a 1 ohm resistor in parallel with stator leads:
5VAC @ idle
11VAC when revved up

No resistor on stator leads
9.5VAC @ idle
30VAC when revved up

I also hooked up the 2 stator leads to a halogen shop light. It was dim at idle, bright when revved up.

The wire from battery to rectifier has an ATO blade style fuse. I took the fuse out, and inserted an ammeter, red closest to battery. At idle, current was -6A, and when revved up -1A. So I guess this means that current is flowing from battery, not to the battery.

So, is the rotor/stator done for or what?

 

[Loffer]

It is said usaully the rotor is weak most times the Stator is ok. You woud get a large spike in charging like 13.5 to 14v when its good.

 

[Tony the torch]

don't make that judgement yet, you can test the diodes of the rectifier with the diode test function on a multimeter or you could go to Radio shack and get a $4.00 bridge wave rectifier and see if that is the problem, then you could also have a zenor diode that is causing all the problems, in that case, unplug it and see if the charge rate goes way up. If all that checks out then put a new rotor in it.

FYI... most people have dumped the stock solenium rectifier and zenor diode by now and have gone to a solid state charge unit like a Podtronics or others. those 2 things may go out soon after you put a new rotor in it.

 

[Cosmo]

Years ago, when Morrie was alive, I went to buy a new stator from him. He stated then that they simply do NOT go bad, and that I had a different problem.

I did, it was the wiring to the rectifier.

Further, only use a Lucas rectifier. All the others will die sooner than later. Guess how I know??

A Triumph charging system is just about the most reliable in the world. The wires that run to and fro - not so much. Suspect them.

Cosmo

 

[Glider]

If you have the original rectifier (square with big fins) do yourself a big favor and toss it (along with the zener) and mount a tympanium or another readily available, modern solid-state rectifier.

If you're not seeing a voltage rise when you rev it up, it ain't charging, and it's almost always the rectifier.

 

[bochnak]

I swapped out the rectifier for one from Radio shack with no improvement.

I disconnected the zener diode lead while bike was idling with no change.

don't make that judgement yet, you can test the diodes of the rectifier with the diode test function on a multimeter or you could go to Radio shack and get a $4.00 bridge wave rectifier and see if that is the problem, then you could also have a zenor diode that is causing all the problems, in that case, unplug it and see if the charge rate goes way up. If all that checks out then put a new rotor in it.

FYI... most people have dumped the stock solenium rectifier and zenor diode by now and have gone to a solid state charge unit like a Podtronics or others. those 2 things may go out soon after you put a new rotor in it.

Tony, I swapped in a RS rectifier with no change. I also have disconnected the zener with no change.

 

[bochnak]

Years ago, when Morrie was alive, I went to buy a new stator from him. He stated then that they simply do NOT go bad, and that I had a different problem.

I did, it was the wiring to the rectifier.

Further, only use a Lucas rectifier. All the others will die sooner than later. Guess how I know??

A Triumph charging system is just about the most reliable in the world. The wires that run to and fro - not so much. Suspect them.

Cosmo

Cosmo,

I just ordered some parts from Morries. The wiring from stator to rectifier checks out. I have 0.5 ohms between the 2 leads and infinite resistance from each lead to earth.

 

[bochnak]

BTW, I have one more Q:

This bike has a Boyer ign, do they draw more power? Or less?

How many watts does a stock rotor/stator put out? I'll have to check the wattage on the headlight. Is a stock headlight 35W?