Re: Vespa Bravo has spark won't start

Ike Pipe /
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Oy.... The light bulb thing.....for crying out loud. The bulb thing is not right. A broken bulb, or a missing bulb won't prevent spark UNLESS YOU ARE PULLING THE BRAKE. But who pulls the brake when they're trying to find spark? Nobody.

LOL Get it together, Vespa guys!

Other than that, good job.

At the OP, if it has spark, you need to check strength. It has to have powerful spark in order to run. It looks like you have an old HT (external) coil. It might be that that is bad. They go bad often enough. An adjustable gap spark tester is the tool for the job. You need the spark to jump a good cm or half inch to be strong enough. I had a Bravo that had spark, but I didn't realize it was too weak. I spent 6 months checking and fixing every single thing . In fact, even the HT coil was new.

Unfortunately, you are not starting from scratch. If you had all those mods and it ran, that would be great. But since it doesn't, and you have no way of knowing what was actually done to that engine, you can't count on anything.

So, you need to start with the assumption that every single part is bad and needs repair or replaced. You need to systematically overhaul and/or clean/test every part of the system. I'd look up Fred's guide in the Wiki and start there. Also, google "Vespa Bravo Haynes" and download the repair manual. Even with aftermarket parts, it will help you refurbish your bike.

If you have solid, strong spark, then it can only be fuel (clean the carb, use a filter with new fuel line, and clean the petcock) or air. Air includes air leaks and bad compression. I have a friend who's Ciao engine was perfectly sealed, and it ran fine as long as you were on the throttle, but died every time he stopped. Bad decomp leaked so bad he didn't have good compression. Air leaks are usually from a bad crank seal or at the carb.

But, that is what I assume when I deal with stock bikes for the first time. With a modded bike, there are absolutely no guarantees about anything. Assume it is bad until you prove it is good. It is the only way. Unless you get lucky. And I never do. LOL

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