Nevada 93 reg

I have an old Nevada first registered 1993 though the frame label says its 1991. Not too important. Bought the bike as a real barn find several years ago about a mile away from my house for £250.00 - delivered to me on the loader forks of a tractor. 14K miles on the clock which I think are genuine as I have a fair bit of history. I have to say its not Motoguzzi’s finest styling in my opinion but since acquiring it we have had it running and on the road. Its now styled more so as a ratty bobber. However it is now being stripped and given some proper attention - full strip down and rebuild and re style. So my question is regarding the electronic ignition. Its a mess. It has a Lucas AB11 electronic ignition amplifier and has works fairly well apart from atrocious wiring by whoever fitted it originally which intermittently fails or becomes disconnected ( I presume its isn’t the original NEVADA standard issue. Has anyone any experience of this or can recommend another system. Ours has Diodes in line which I have never seen before and look like a nut and bolt with cable at either end. Should these be exposed? I have shrouded them in heat shrink since they seemed to be vulnerable to unwanted contact with other parts. Not sure if this is correct. I am trying to find a wiring diagram so that we can rebuild the wiring and hopefully eliminate the possible issues we have had so any comments or help would be appreciated. When it runs its is a really nicely balanced bike, terrific handling and tons of acceleration and power with an amazing engine and with new short cone silencers sounds like a harley with attitude.



I had a Lario that I was working on a few years ago and recall the wiring diagram for that called for diodes on the coil wiring. A quick google search has come up with this for the V50 that wll be the same principal.

Lots of info on Rita’s available here…

Rex Speed Shop do offer new electronics to go inside the box if it is looking faulty.

Is this any good:

I got Nevada with Rita in. Will post some pics later; in general: it does the job. No more, no less.

Thanks for all the pointers

I think the system is sound and the wiring is the dodgy part. The diodes were bare and have now been shrouded in heat shrink. Wiring diagrams seem spot on.


On another note trying to extract the Suprisa rotor from the crank shaft. Have fashioned my puller on the lathe but it refused to pull off. I don’t have any instructions for the nevada 1991 for for this type of unit (only dealt with the old bosch systems) so I assuming it is a simply tapered shaft as with my V50’s with or without a key - not threaded or something? Going to apply some heat unless told otherwise and try again.

I can’t remember exactly how I got the rotor off on my Lario, but I would try the same extractor as used on the Bosch one, either a length of hardened steel popped in the hole to push it off, or one of these long bolts that grips the thread in the rotor and pushes it off from the bottom of the hole in the crank. I would be reluctant to use heat on it.

…and please don’t put a non-hardened spacer, like a drill bit, in the bolt hole and then tighten up the bolt to pop off the rotor, just don’t and don’t ask how I know! My bike came to me with a short length of allen key shaft that had been hardened, take off the bolt, pop in the spacer and replace the bolt. The thread on the bolt then grips only the rotor and so draws it off the end of the crank shaft. These days I have a proper tool like the one Dom has pictured above, and it works a treat. I too would not advise heat.


I have turned something resembling this on my lathe from a 8mm bolt and will try again without heat.

Thanks for the pointers


This device will work if there is a thread in the rotor itself. The bolt then bottoms out in the hole in the crank and pushes the rotor off.
I do know it works on the Bosch rotor, but not sure on the Saprissa ones.

I just use a short length of hex key. 5mm I think, and maybe around 53mm length - can’t quite remember now.

Nigel at NBS I think uses a hammer. Holds a 5lb club on one side of the rotor and then strikes the other with similar.

All off with a bit of pressure but really tight.

Thanks everyone