v50 rectifier wiring

Technical Small Block V Twins (not new V7s)
1

HELP. Bought a Bosch style rectifier from gutsibits but it came without a wiring schematic. I am rebuilding a barn find v50 II which came with the old one disconnected. I am not very good at electrics and although most plugs are obvious I don’t know which small terminal the small red wire connects to. The other small ones i think are earths. Thanks Bazza 623

2

I can send you a pdf of the wiring diagram in colour that may help. I would need to know if the bike has points or electronic ignition.Â

See here http://www.motoguzziclub.co.uk/phpbbforum/viewtopic.php?f=64&t=16390

Best wishes Chris

3

The mk II will be factory fit electronic ignition.

4

Quick pic…

5

this is my small block, the two (or in some cases only one) heavy red wires connect to the big spade connectors on the top right of picture, the one and only earth wire (the one with black tape) goes to the bottom half of the unit, the top half is ‘live’ and the bottom half is ‘earth’ do not connect the earth wire to the top half [URL=http://s260.photobucket.com/user/aaa999777/media/DSCF0440.jpg.html][/url]

6

Thanks guys, the photos help a lot. I have a colour wiring diagram but it is schematic and I find interpreting it difficult. Â regards Bazza

7

3 x yellow = alternator 3 phases; red = output to regulator; pale blue = dashboard charge warning lamp; darker blue = (I think) alternator again, stator windings centre-tap. Some rectifiers don’t have this connection, at least mine doesn’t.

8

make sure you check out all the earth points properly. melted 2 earth wires on my v35 till i twigged the earth to the front brake reservoir under the tank was bad

9

Reminds me, don’t know about V50 but I completely rewired my 850 Tonti in 2013 with all new homemade looms, in the process I found that originally the black rectifier earth wire went to a tag on a bolt that also held one of the battery side rubbers ~ that meant it couldn’t be tight else it would crush the rubber, so that meant the connection WAS LOOSE! As it happens the rectifier neg side screws directly onto the sub-frame which in turn is bolted to the main frame, but even so.

I now have the rectifier neg wire connected direct to battery negative terminal, and thence to rear gearbox cover via the big starter gauge earth cable.

10

its interesting to compare my 1977 v35’s wiring with my new v65tt and see where Luigi finally learnt from his mistakes!Â