Monster MONZA TAT BUILD

BUILD DESCRIPTION

Why did I build this: In mid 2013 I was told about a grand moped adventure. Trying to ride mopeds across america with out touching pavement. This 5,000 mile journey is called the Trans American Trail, or TAT. A few brave soles and myself attempted the journey during the summer of 2014. To our knowledge no one had ever attempted to ride the trail on such undeserving and under powered bikes, 50cc mopeds. The TAT is a harsh rout that is usually reserved for rigged Jeeps or purpose build dull sport motorcycles that goes through 10 states, has altitude ranges from 0 to over 9,000ft, and includes a incredibly diverse range or terrain. As a result, we had to modify or mopeds to handle....... anything. The build details: The engine: This started life as a 1980 Garelli Monza GT. The stock 2 speed engine was ditched in favor for a single speed 50cc Franco Morini s6-c motor. Typically it can be found in kids racing dirt bikes from the early 2000's. It is far from a direct bolt up, requiring custom engine mounts to be made and additional structural bracing to be added to the frame. However, I chose this engine because it has close to the same profile as the original and would be far more reliable and much more powerful. The stock VIP motor has a notoriously poor performing 2 speed clutch, only has around 2hp. The Franco Morini engine is far more modern, and the clutches can be tuned to engage at any rpm you desire, giving you 11.5hp in the power-band. I also chose this engine because it is still "moped-ish." Although never used in a production moped, variations of the same Franco Morini engine were. Also, it is still 50cc and single speed. Keeping it in line with what makes a moped... a moped. -------------- The Frame: The Monza frame looks pretty solid from a distance, but when you get into looking at how it was designed you realize that the back half of the frame, containing the rear shock mounts and the mount for the swing arm, is only held on to the rest of the bike by thin gauge stamped steel. To beef up the frame, there was a plate and cross bracing added to better connect the front half of the bike to the rear. The Suspension: The front end uses 40mm Marchozzi hydraulic inverted forks. They performed amazing on the ride and made the bike feel a lot more solid and planted. To make them fit the frame, I cut the stock steering tube out of the Monza triple tree. Lathed down the base and press fit it over the top of the Marchozzi's steering tube before welding the two together. This made the the much larger aftermarket forks bolt directly up to the Monza frame without needing to modify the head tube. The forks also raised the ride height of the bike up by 5." To compensate, I used 15" rear progressive shocks from a 1971 Husqvarna 175. The Wheels: I used 16" x 3" aluminum 28 hole Pro Race rims wrapped in Shinko 16 x 3 knobby tires. The front hub is a small disk brake hub from a kids dirt bike. I intentionally ran a smaller front brake so I could slam on the brakes and not worry about the locking up and washing out the front end. The rear hub came out of a 70's Suzuki RM100, that allowed me to run a 8" rotor and a dull caliper rear brake. To fit the rear hub, the rear swing arm had to be modified because the hub is quite wide and ran a 16mm axle. Ignition: The factor ignition for the Franco Morini s6-c is actually rev limited and dosn't contain a lighting coil. There are also no aftermarkett ignitions for this engine. Because I wanted my bike to rev to the moon and have running lights, I had to do a bunch of research into what might fit. The closest I could find was a HPI mini rotor ignition for an obscure Honda scooter only sold in Europe... However, it still needed significant modification to fit the taper of the s6'c crank. I needed to create a custom stator plate to mount the coils to and the taper on the rotor was drilled out and a custom lathed taper was created and then press fit inside the HPI's rotor. The end result was an amazing unlimited ignition and 60W lights! Odd's and Ends: Headlight is from a Honda Ruckus. I modified a factory Monza rack with rails to lock in 2 metal 2 gallon jerry cans for extra fuel capacity.