Britbike forum

Classic British SparesKlempf British PartsBaxter CycleBritBike Sponsor SteadfastCyclesThe Bonneville ShopLowbrow CustomsGirling Classic MotorcycleLucas Classic MotorcycleHepolite PistonsIndustrial tec supply Classic Bike Parts Cheshire

Upgrade Your membership! Premium Membership Gold Membership Vendor Membership

New Sponsor post
July 4th Sale at The Bonneville Shop
by The Bonneville Shop - 07/01/22 6:26 pm
New FAQ post
Member Spotlight
Mr Mike
Mr Mike
Cape Carteret, NC
Posts: 4,037
Joined: August 2001
ShoutChat
Comment Guidelines: Do post respectful and insightful comments. Don't flame, hate, spam.
Top Posters(30 Days)
kevin 71
Lannis 70
quinten 61
Top Likes Received (30 Days)
Lannis 23
MikeG 22
Newest Members
Boardtrackracer, Glen, Dave100, Scott Meredith, JOB
12,219 Registered Users
Who's Online Now
4 members (L.A.kevin, Carl, Stuart Kirk, kevin), 8 guests, and 22 robots.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums35
Topics76,578
Posts776,841
Members12,218
Most Online204
Jul 10th, 2022
Previous Thread
Next Thread
Print Thread
Joined: Jul 2020
Posts: 20
C
Britbike forum member
OP Offline
Britbike forum member
C
Joined: Jul 2020
Posts: 20
Hello.. and thanks in advance for any advice anyone can give me

My regulator went bad, and I fried a couple batteries before I realized what was going on. I disconnected the regulator and swapped out the rectifier for a Tympanium single phase rectifier/regulator. Initially everything tested out ok... The voltage was around 14.5 volts when i rev'ed the engine. So, I figured everything was ok.

I drove it for a few days, when it suddenly started running rough. I tested the voltage, and it was running up over 16 volts. At the time I assumed I didn't connect the wires right and one was loose. I decided to strip the connecters off... and twist the wires together and solder them together. Thinking that would provide the best connection.

The connections on the wires seemed solid after I was done, but when I retested the bike... The voltage was jumping up over 16 volts. So, I'm wondering if the new rectifier/regulator might be bad.

Can someone tell me if there's a way to test if it's good or bad?

BSA on eBay
Joined: Jan 2014
Posts: 2,178
Likes: 377
N
Britbike forum member
Offline
Britbike forum member
N
Joined: Jan 2014
Posts: 2,178
Likes: 377
Although unusual, a bad connection can cause the regulator to fail.

If the regulator is connected well to the alternator and to the battery,
you should be able to measure around 14.5v dc at the battery when
the bike is revved to around 3k. If it is substantially more then the
regulator is not doing it's job.
What type of meter are you using to measure the voltage? I ask
because some digital meters may flicker around when presented
with a relatively 'raw' supply. Normally the battery will smooth out
the supply but not always. Tympanium units i have seen over the
years have a single scr type regulator so may present a rougher
waveform than other types which tend to use 2 scr's in inverse
parallel.
Measure with an analogue type instrument to make sure.

Joined: Jul 2020
Posts: 20
C
Britbike forum member
OP Offline
Britbike forum member
C
Joined: Jul 2020
Posts: 20
Thanks for the reply

I'm using a digital meter... When I initially installed the rectifier/regulator, the voltage tested out around 14.5 volts when i rev'ed up the engine, and iI didn't see the volt meter spike or jump higher than that. The battery charge was 12.6 volts. And at the time I thought the problem had been fixed. After I retested the battery voltage this time, the voltage had dropped to 11.6. Which is why I decided I hadn't fixed it.

To retest the voltage after I soldered the wires together, I bought some alligator clips for my meter, to attached to the battery leads. I figured they'd be a better way to monitor the voltage verses just holding the probes against them. The voltage was bouncing around, but the voltage hit 19+ volts at one point. I went ahead and tossed my battery on a trickle charger last night, and the trickle charger said it was charged. Although I haven't tested the battery with my meter yet. I'm going to check the connection on the wires tomorrow to double check they haven't come loose.

I saw on another thread; someone was asking how to test their rectifier (I think it was for the Lucas rectifier). The replies said connect the negative meter lead to what would have been the center tap, and the positive meter lead to the wires going to the stator. And the reading for a functioning rectifier should be 400 ohms... Do you know if this would test out for a single phase?

Thanks for the advice... I appreciate it

Last edited by Chitown guy; 07/27/22 12:23 am.
Joined: Aug 2001
Posts: 9,141
Likes: 188
T
Britbike forum member
Online Content
Britbike forum member
T
Joined: Aug 2001
Posts: 9,141
Likes: 188
I’d try another reg/rec.

These are cheap-ish and work well for me.

https://www.ebay.co.uk/itm/20378320...r=&widget_ver=artemis&media=COPY


Amateur Loctite enthusiast.
Joined: Mar 2011
Posts: 270
Likes: 22
L
Britbike forum member
Offline
Britbike forum member
L
Joined: Mar 2011
Posts: 270
Likes: 22
if you are using a cheap digital instrument

https://www.bol.com/nl/nl/p/profess...gdmjtJ8dl63TQNhOKiLGN8lcBSIaAkXcEALw_wcB

the voltage reading goes up when the 9V internal batterij goes flat
how do I know, now using a fluke 179

Last edited by lemans; 07/27/22 7:04 pm.
Joined: Sep 2013
Posts: 3,845
Likes: 270
Q
Britbike forum member
Offline
Britbike forum member
Q
Joined: Sep 2013
Posts: 3,845
Likes: 270
Sounds like you just got a bad voltage regulator .
You hooked it up correctly and it just crapped out early .
it was Dead Before You soldered it back on .
was it sold with a warranty . ?

Joined: Sep 2007
Posts: 1,601
Likes: 20
Britbike forum member
Offline
Britbike forum member
Joined: Sep 2007
Posts: 1,601
Likes: 20
I’ve had good and bad luck with Tymps. Finally went to a Podtronics unit.


Who are the Brain Police?

B44 Victor
60 MGA
56 Chevy

Bob M.
Joined: Jul 2020
Posts: 20
C
Britbike forum member
OP Offline
Britbike forum member
C
Joined: Jul 2020
Posts: 20
I'd like to thank everyone for their reply

Although I'm still wondering... Is there's a way I can test the rectifier/regulator to verify it's bad? I bought it from a local garage, and I'd like to make sure it's bad before i take it out of my bike and take it back to them.

Thanks!

Last edited by Chitown guy; 07/28/22 1:03 am.
Joined: Aug 2001
Posts: 237
Likes: 16
M
Britbike forum member
Offline
Britbike forum member
M
Joined: Aug 2001
Posts: 237
Likes: 16
there are 2 AC input leads and 2 DC output leads. put your meter on a scale that reads diodes. most meters have a special function position to do that. a "diode number" is something like 400 -800 ohms)

place the meter + lead on one AC lead and other meter lead on one DC lead.... you should get either "yes" or "no" (400 or infinity). reverse the leads and you should get the other reading. repeat with meter + lead on the other DC lead

then put the meter lead on the other AC input lead and repeat the above

no set under test should read continuity in both directions, and no set should read infinity in both directions. continuity with a higher reading than other pairs is probably bad

a bad ground connection can make the regulator over volt

Joined: Aug 2001
Posts: 5,905
Likes: 116
M
Britbike forum member
Offline
Britbike forum member
M
Joined: Aug 2001
Posts: 5,905
Likes: 116
Originally Posted by Chitown guy
I'd like to thank everyone for their reply

Although I'm still wondering... Is there's a way I can test the rectifier/regulator to verify it's bad? I bought it from a local garage, and I'd like to make sure it's bad before i take it out of my bike and take it back to them.

Thanks!

I think the test you ran is sufficient. There's no way you should be getting 16 volts out of that unit, and I can't see any other cause for that besides a faulty regulator.

Originally Posted by Mitch
...a bad ground connection can make the regulator over volt

This is true only for zener diodes, which are connected in parallel with the rectifier. A disconnected zener on either side will result in no voltage regulation.


Mark Z

'65(lower)/'66(upper, wheels, front end, controls)/'67(seat, exhaust, fuel tank, headlamp)/'70(frame) A65 Bitsa.
Joined: Aug 2001
Posts: 237
Likes: 16
M
Britbike forum member
Offline
Britbike forum member
M
Joined: Aug 2001
Posts: 237
Likes: 16
nope... its true for any regulator... even one that gets its ground through it's case. resistance in the ground connection means a higher voltage must be applied to overcome the extra resistance. the regulator is not accurately seeing the battery/system voltage. that drives the system voltage up. same is true of extra resistance in the main power lead but it is usually the ground side that has the problem... especially with positive ground where the frame is anodic to the rest of the system. many generator systems have a dedicated wire from the generator to the regulator for that purpose.. it carries no load, it only keeps the potential between the two at the same value

1 member likes this: NickL
Joined: Aug 2001
Posts: 5,905
Likes: 116
M
Britbike forum member
Offline
Britbike forum member
M
Joined: Aug 2001
Posts: 5,905
Likes: 116
Ok, I learned something today; thank you Mitch.

Now if the regulator responds to resistance, does this not imply that a bad battery could also cause an abnormally high charge voltage?


Mark Z

'65(lower)/'66(upper, wheels, front end, controls)/'67(seat, exhaust, fuel tank, headlamp)/'70(frame) A65 Bitsa.
Joined: Aug 2001
Posts: 237
Likes: 16
M
Britbike forum member
Offline
Britbike forum member
M
Joined: Aug 2001
Posts: 237
Likes: 16
yes... I have seen that happen


Moderated by  Allan G, Jon W. Whitley 

Link Copied to Clipboard
British Cycle SupplyMorries PlaceKlempf British PartsBSA Unit SinglesPodtronicVintage MagazineBritBike SponsorBritish Tools & FastenersBritBike Sponsor






© 1996-2022 britbike.com
Powered by UBB.threads™ PHP Forum Software 7.7.5