Testing regulator output voltage?

[retskcid]

I tested the alternator with the correct setting on the meter and its fine - output well over 30v to 75v when I rev the engine.

I plugged the alternator back in and unplugged the output connector from the regulator into the loom and restarted the bike. Tested with the voltmeter and I am getting no more than 7.5v - whether I rev the bike or not. Shouldn't this be 14+ volts? In which case I need a regulator. Or is this not a valid test?

I did notice that the three yellow alternator wires get warm and the connector even more so - but not melted yet!


Rich

[Sparky]

You would normally test the charging system with everything plugged in so I'm not sure how the regulator will behave off load. With everything plugged in and the bike off the voltage at the battery terminals should be aound 12.5V, with the engine running the voltage at the battery terminals should be higher but no more than 14.8V at say 3000-4000rpm.

If the yellow wires and connector are getting hot then it does sound like your regulator is f@@ked and to be honest I wouldn't run it like that for long as you'll fry the alternator.

Chris

[retskcid]

Cheers Chris,

I am going to fit a digital voltmeter to the bike first (so I know exactly whats going on all the time) and then I am thinking of one of these:

http://www.tpoparts.com/catalog/product_info.php?products_id=53&osCsid=3f92b340dc9c7da73576aab43f95702f#

on the basis that heat kills the RR.

Rich

[Scotty]

ooh interesting

[retskcid]

ooh interesting


Hello Scotty,

I found one of your posts one another forum, can't remember the forum now, but you were having electrical problems?

I just want to diagnose and sort out the faults that the bike has and then do what I can to ensure realiability in the future. That product is cheap enough and sounds like a good idea from all the reading I've been doing on the subject of RR's.

Rich

[retskcid]

I used a digital voltmeter tonight and got 12.8v before I started and about 13.1v max with the engine running, whatever revs. I also noticed the three yellow wires and connector plug were very warm within a couple of minutes of starting the engine.

Definitely the RR then I'm thinking?

Rich

[Sparky]

13.1V is def too low, mine is usually around 14.5 after starting and 12.8 before indicates that the battery is fully charged. Are you having problems with the battery going flat then?

Chris

[retskcid]

13.1V is def too low, mine is usually around 14.5 after starting and 12.8 before indicates that the battery is fully charged. Are you having problems with the battery going flat then?

Chris

Yep, I have to keep it on charge the whole time to have any chance of starting it. I'm going to order an RR today so fingers crossed.

I am probably going to buy a couple of TPO products to relocate the RR as well.

Rich

[nabbott]

Spookily enough I 'think' my RR has also just died (whilst commuting in London on a REALLY hot day - JOY!). The tests conducted by the RAC showed nothing coming out form the reg. so have just replaced it (loads coming from the generator), and all appears fine:

http://www.electrexworld.co.uk

£72.86 all in.

Voltage across the battery is now 13.8 (at tickover) rising to 14.4+ through a few light revs. BUT here's my question.... my RR is only wired for 2 yellow wires. I assume that ducati take three wires from the generator to split the load - can anyone confirm this?

[Sparky]

BUT here's my question.... my RR is only wired for 2 yellow wires. I assume that ducati take three wires from the generator to split the load - can anyone confirm this?

Your generator produces an alternating current so the voltage waveform is sinusoidal. If you have three yellow wires then you have what is known as a three phase alternator where the alternator produces three sinusoidal voltage waveforms each with a phase shift of 120 degrees.

If you only have two yellow wires this implies your generator is single phase ie a single sinusoidal voltage waveform. You get both a single and three phase RR so you should choose the one that matches your generator.

Chris

[retskcid]

Those numbers sound good now, and I hope to get a replacement by the weekend and achieve the same. FYI the Ducati RR I have ordered is £59! (Moto Rapido)

[retskcid]

New RR fitted. I seem to have more volts but is this right - at idle I get around 13.5 to 13.8, and riding 13.9 to 14.2. The volts do fluctuate a bit all of the time, is that usual or should they be completely stable?

[Scotty]

sounds good to me

[retskcid]

cheers scotty, now for the starter clutch.

i should have it done in time for next summer....