Modern Buddy

In late June of 2014, I posted this...

az_slynch wrote:Bought a Motobatt for my '83 Riva 180, which are notorious for being hard to start. Part of it's the carburetor, the other part is starting voltage. The Motobatt has made it a lot easier to start and tolerates the run-on load of the carburetor cooling fan with no issues.

I'd bought the battery in December 2013 for the Riva. Took the bike to the 5th annual Great Southwestern Scooter Fiesta. While participating in a group ride, I lost the rear axle bearing and parked her up. The bike has been lurking in my garage since then, only moving when I need to roll it out to take out or put away the spa-pool covers. The battery hasn't been on a tender and it has been wired to the bike the whole time. This last weekend, I switched the bike on for funsies.

The lights still lit and the carb fan still runs. Twenty-three months later, with nothing but negligence! Feling guilty, I pulled the battery and put it on my NoCo Genius 1100 charger. Still had over 25% charge and was back to full strength overnight. Tested A-OK.

Motobatt, call me impressed!

nice! Like the riva 180?

skully93 wrote:nice! Like the riva 180?

Truth be told, it's like owning a vintage Jaguar. It's brilliant when it runs, but it breaks your heart when it doesn't. Power is good for the displacement and it can be pushed to 70+ if required. The ride is pretty compliant and soaks up the road pretty well. Handling is decent, but it's a bit hefty for it's size. It has nice features like a sidestand warning system, a trip meter with a pushbutton reset, hydraulic valves that do not require adjustment, a thermal monitoring / fan cooling system for the carburetor and an illuminated keyswitch ring, which is activated by pushing the horn button when the bike is switched off. Deluxe versions had a LCD dashboard and self-cancelling turn signals. In some ways, it's ahead of it's time. In other ways, things like a multiplate dry centrifugal clutch and a thermal/vacuum management system for the carburetor were not great ideas for reliability.

Parts are getting scarce, so when something breaks, it's a bit of a job to fix things. I've been hunting for OE spares for a while now in order to refurb the transmission.

our local shop has had one forever. they keep putting it up for sale, then it gets gummed up again. I think they should just do a silent auction for it and be done.

skully93 wrote:our local shop has had one forever. they keep putting it up for sale, then it gets gummed up again. I think they should just do a silent auction for it and be done.

They need to drain out the fuel bowl once they park it up. These bikes are notorious for their starting circuit going bad. The fuel system doesn't have a electromechanical bystarter like the '85-on Hondas, but rather a solenoid controlled vacuum circuit. It's a convoluted bit of vacuum hose and has a ridiculously tiny jet embedded in the carburetor bowl to feed it. I usually fill the bowl with boiling water to soften the sludge and then blow it out with compressed air. For the few Riva 180s I've worked on, the problem usually lies in the pilot circuit more than the starting circuit. The material of the pilot jet is very brittle and it seldom wants to come out of a carburetor after thirty years. Twice now, I've just ordered new pilot jets and then tapped a small Torx bit into the old one to remove it. That will only be viable as long as new pilot jets are available. Carb bowl gaskets are NLA, so use caution when removing the gasket and float it in some Gummi Pflege to restore some pliancy to it for another term of service.

They also need a "perfect" battery to start reliably.