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| As shown from the intake transfer side of the cylinder, the Malossi cylinder has much larger transfer ports than the stock cylinder on the right. |
We thought the RS50 would be a cool project because of its uniqueness, its fuel economy and its alternative scooter attitude. It just looked plain badass, it would make Vespa riding fem Mods quake. Our first test ride proved that we would not be scaring many people except perhaps stock Honda Ruckuses and people on Chinese scooters. The high strung AM6 had a powerband of about 2000 rpm and you had to rev to the moon and row the six speed gear box like crazy to barely keep up with traffic. The engine sounded like a little YZ80 dirt bike and people would stare. Perhaps the worst thing was that since the RS50 looks like a GP bike, motorists expected GP bike performance and would tailgate impatiently. This was not fun.
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| Guess which piston is the Malossi big bore one? |
The bike handled and braked very well and in residential streets you could pretend you were Rossi and hang a knee out and corner at Scooter crashing speeds. At only 200 lbs the RS50 could probably out handle a big bike in very tight corners. Fully tucked and rung out, our bike was able to do a little more than 55 mph which is pretty respectable for a stock 50cc.
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| The heavy duty Doppler crank has silver plated bearing cages for better heat conduction, stronger bearings with more rollers, stronger rod and full circle counterweights. It is designed to take up more crank case volume for better breathing at high rpm. It is also designed to be stronger so you can safely rev to 13,000 rpm up from the stock 11,000. |
We decided that we should give Project RS50 a full restoration and substantially beef up our engine. We contacted our friends at AF1 for help and advice. AF1 is an Aprilia motorcycle and scooter dealer with a racing background. They also have extensive experience racing and modifying the RS50. They had previously helped us a lot with Project SR50. We bought all of Project RS50’s OEM parts from them. We also got a lot of information from their forum Apriliaforums.com. We sourced a lot of our parts from overseas mail order houses. With the Internet, parts can be easily ordered and shipped from overseas with very little additional expense. Most mail order houses that have performance scooter parts also stock parts for the RS50.
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| The Delta V reed valve on the right has twice the reed area as the stocker on the left. It usually gives a full horsepower increase on small engines like ours. |
