19753C(E)
Full member
- Location
- Wisconsin, USA
Hi all - took the SF2 out for the first time this spring. Runs fine but the generator light comes on whenever I turn on the lights. Is my generator toast?
'75 SF2 generator
- Thread starter 19753C(E)
- Start date
Laverda SF
Hero member
You could take off dissemble and clean the generator (dynamo) but more then likely the Bosch WTF is the name of that thing - Man I'm getting old! The REGULATOR ;o)
They tend to rattle to death on 750 Breganzies if you don't isolate them in rubber mounts.
There are supposed to be some modern Transistorized replacements out there for the "BOSCH" Laverda Regulator out there that claim to do the job ?
Always wished my SF came with a Zenor Diode but then I might not have Electric Start - LOL
They tend to rattle to death on 750 Breganzies if you don't isolate them in rubber mounts.
There are supposed to be some modern Transistorized replacements out there for the "BOSCH" Laverda Regulator out there that claim to do the job ?
Always wished my SF came with a Zenor Diode but then I might not have Electric Start - LOL
Tippie
Hero member
- Location
- Dr?bak, Norway
Was the generator light working correctly before the winter? If you did any wiring work over the winter you may have it wired incorrectly (the globe has switched power to one side and the other side goes to a regulator terminal D+ if I remember correctly) but worth checking. Does it stay on when you rev it higher? Is your dynamo belt tight? Is the earth wire from the regulator well earthed? Are all the wires to the genny and reg well connected and in good condition?
Do the standard voltage over the battery terminal test to see if volts rises, and to what, both with and without headlights on, should rise to around 14-14.4vdc. If that?s ok you need to check amps, easiest with one of the magnetic ring clamp type multimeters, otherwise running the B+ wire through an ammeter, noting how it is both without and with headlight load. It should show at least a few plus amps when revved. If both of those are ok your battery is charging regardless of the globe lighting up. If either isn?t, it is a regulator (very common) or generator (less common) fault. To isolate it to which item you can do the generator tests that a search of this forum will bring up, I don?t know of any test of the regulator in isolation. Electronic regulators are now widely available if that is the culprit.
Do the standard voltage over the battery terminal test to see if volts rises, and to what, both with and without headlights on, should rise to around 14-14.4vdc. If that?s ok you need to check amps, easiest with one of the magnetic ring clamp type multimeters, otherwise running the B+ wire through an ammeter, noting how it is both without and with headlight load. It should show at least a few plus amps when revved. If both of those are ok your battery is charging regardless of the globe lighting up. If either isn?t, it is a regulator (very common) or generator (less common) fault. To isolate it to which item you can do the generator tests that a search of this forum will bring up, I don?t know of any test of the regulator in isolation. Electronic regulators are now widely available if that is the culprit.
CLEMTOG
Hero member
Come on Ron!
you are old enough, ugly enough and daft enough, to know that 750 twins, had a Bosch dynamo and a Bosh regulator ( a very few, right at the end, had an alternator)
LUCAS?
not in the charging system 'ol chap
those Bosch parts can be obtained/serviced etc at air cooled Volkswagon outlets, the dynamo is very similar to the VW variant (not the double ended one fitted to a Beetle. although some parts interchange) and the regulator is similar to most air cooled VW's
CLEM
you are old enough, ugly enough and daft enough, to know that 750 twins, had a Bosch dynamo and a Bosh regulator ( a very few, right at the end, had an alternator)
LUCAS?
not in the charging system 'ol chap
those Bosch parts can be obtained/serviced etc at air cooled Volkswagon outlets, the dynamo is very similar to the VW variant (not the double ended one fitted to a Beetle. although some parts interchange) and the regulator is similar to most air cooled VW's
CLEM
Tippie
Hero member
- Location
- Dr?bak, Norway
Most of the mechanics who knew those old VWs are retired now though, Clem. These days mechanics just learn which new software to flash in, not how to adjust a vibrating contact regulator to a dc generator, I doubt it is even part of tradeschool curriculum these days. The VW car regulator can work, but I had several of them fail after short time, I think that the spec bike one had a far more robust system. As said there are tons of electronic ones available from among others Sachse. If someone really wants to have a huge lump like the original there is one electronic one in the same housing, and others which can easily be fitted into the old housing if it?s for an SFC rivet bike with the reg on show. He aught to trace the source of the fault before he starts buying new stuff. It might be a simple fix.
Furbo
New member
- Location
- Killeen, Texas
Clem is on the $$ here,
It's the fooking regulator. Good news: walk into any self respecting autoparts outlet and ask for a VW (Aircooled) VW from the early 70's and likely as not they'll hand you the updated transistorized no real contacts version of the the part. Have one on my 750 and another on my Guzzi V7.
It's the fooking regulator. Good news: walk into any self respecting autoparts outlet and ask for a VW (Aircooled) VW from the early 70's and likely as not they'll hand you the updated transistorized no real contacts version of the the part. Have one on my 750 and another on my Guzzi V7.
Laverda SF
Hero member
Had to go back a rename "Lucas" to "BOSCH" - Hate getting Mindless !
Lucas built Great Bar switches but their Ignition SX was Darkness.
Replaced the Lucas Ignition SX with an Industrial Toggle SX.
Lucas built Great Bar switches but their Ignition SX was Darkness.
Replaced the Lucas Ignition SX with an Industrial Toggle SX.
chrisk
Hero member
- Location
- Brisbane, Australia
AndyW said:
Even more so that you've made it public
That said, it does sound exactly what was explained initially.
Laverda SF
Hero member
Old School Breganzie Crap ;o)
In rare cases it may be the regulator, the Bosch units are just about bomb-proof (if correctly mounted!). Much the same goes for the dynamo, but brushes do need to be in good order.
I'd be looking at the wiring first, an almost-fractured wire can show the same effect, when current rises, resistance increases, thus "blocking" the circuit. A loose belt will slip as generator resistance rises and more power is called for.
BTW, the only Lucas item I've found on the Breganze machines was the flasher unit, a small rectangular box in a dedicated clip. This unit is shown in the spares books of the SF1-3 range and early triples. I can imagine some importers/distributors may have fitted Lucas indicators to comply with local regulations. Never have I seen a Lucas ignition switch...
piet
I'd be looking at the wiring first, an almost-fractured wire can show the same effect, when current rises, resistance increases, thus "blocking" the circuit. A loose belt will slip as generator resistance rises and more power is called for.
BTW, the only Lucas item I've found on the Breganze machines was the flasher unit, a small rectangular box in a dedicated clip. This unit is shown in the spares books of the SF1-3 range and early triples. I can imagine some importers/distributors may have fitted Lucas indicators to comply with local regulations. Never have I seen a Lucas ignition switch...
piet
Laverda SF
Hero member
Lucky for you = "PRINCE of Darkness"
You and I agree on a lot of things Breganzie wise that is ;o)
That Lucas "Prince of Darkness" Ignition Switch was prevalent on late 69's and early 70 Eruo Bikes. Including my 69 Bonny.
Looks Great and Solid BUT Rattles to SHIT.
Believe me FUCK the LUCAS Key.
It will Kill you with an 18 Wheeler running over your ass - Just get RID of it and use an Industrial Toggle Switch.
This will kill you:
This will save your life:
Jo
Hero member
- Location
- Cologne, NRW Germany
sfcpiet said:
I would follow Piet's suggestion. On my 750 I once found a half-broken ring terminal on the Bosch regulator
- it cost me a few tries to find this mistake ...
Cheers
Jo
Laverda SF
Hero member
Yes the BOSCH Regulator rattled it self to death on my 70 750 SFO and it did indeed have the Prince of Darkness Lucus Ignition SX - 1 of 200 SF's Exported to Canada back in 72 disassembled in crates 2 years Late by the time it pasted Immigration - LOL.
Honda and Kawaski's 750 & 900'a destroyed the European market to North America because of that Import delay.
The North American Vs European Imports confrontation was prevalent around the Cold War Era during the late 60's to mid 70's and lingered until the Wall Crashed.
Leaving the 1% of the Worlds Richest to Indulge in a Game of Monopoly at our demise.