Monza re-comissioning

Hi All

Bought an 81 Monza locally from advert here on the forum from the estate of an engineer who had sadly passed away.

It was pretty much up and together although he had been doing some work to it.

Having got a new battery, ignition switch and petrol tank keys cut I started work on it yesterday. All was going smoothly until we connected up the battery. Although most of the electrics were working we soon had a burning electrical smell and smoke! Luckily the tank was still off at this point.

The big block connectors under the tank were fairly hot. After further investigation the first fuse (RH side) was very hot with a red or orange wire going in at the top and a green one out of the bottom. Once the fuse was removed all was ok and interestingly the headlight was full strength whereas with the fuse in it seemed very dim but would still change full low to high beam. The block connector to the rear light was also badly corroded and one of the pins broke away when trying to clean it. So questions are

What does the first fuse do?
Is there a good electrical cleaner to get rid of build up on pins?

Managed to get it running without to much effort and it certainly sounds nice.

Will post a couple of photos or video if I get time.



Sounds like you got a short-circuit to frame somewhere, needs finding and fixing. F1 may a clue as to which part of the circuit. Not sure if it does the same job as on a big block tho

According to my wiring diagram the green wire comes from the ignition switch, via pin 6 of the 15-way connector to fuse number 4. It leaves here as a red wire and goes via pin 4 of the 12-way connector to the Left Handlebar switch cluster, specifically the light switch. The legend on the wiring diagram says “Fuse No. 4 Parking Light - Instrument Lighting - Lighting”. If I remove this fuse on my V50 the sidelight and rearlight do not work when the switch is in the sidelight position but in the headlight position the rearlight comes on and the headlight works on main and dip. It looks as if you have a serious short circuit in the sidelight wiring. As regards cleaning the connectors, I pull mine apart about twice a year, spray with WD-40 and wiggle about a bit. (The connector, not me.) I have not had any problems with them. Good luck.


That makes sense as I had a look at the pilot bulb and it disintergrated in the holder so something is a little awry.

Looking forward to getting it on the road in the near future.


It could be a short circuit and yet I’d be thinking high resistance (corrosion, faulty component etc) due to the heat generated.
Just a thought,

I use Servisol Super 10 from Maplins computer shops, cost about a fiver, you can buy it cheaper on the innernet but if you add in post and packing your local Maplins should be cheaper.I have just re-comissioned a small block Guzzi after ten years in dry storage, took it away this weekend for its first decent ride (140 mile round trip) and apart from noticing a few bolts needing to be given a tighting up the bike was fine,here it is on the M6 (not)

northwest2014-06-08 19:40:54


A V65 SP?

I once saw a Monza once with similar side fairings which looked quite good. Not sure if the V65 ones would fit, anyone know?


Dont see any reason for them not fitting other Guzzi small block bikes, but you would not be able to fit front crash bars as well as the fairing lowers.