While the Aermacchi was in the process of getting restored, we were diving deep into an endless cycle of trying to find vintage vehicle insurance for the bike.

A majority of the top collectible vehicle insurance companies (Hagerty, Grundy, American Collector) requires you to own a CAR in order to qualify for vintage car insurance. I realize a bunch of people must have attempted to game the system by purchasing cheap insurance for their old Toyota Corollas. The underwriters seem to play by the book, not taking into consideration – on a case by case basis – that as city dwellers, we actually choose to use motorcycles as our daily commuters, in lieu of a car, for the sake of economy and practicality. The Aermacchi's a great bike, but a little too precious to use every day.

Thanks to Facebook, which pointed us to State Farm Insurance Agent Lynne Barnhardt who's a bit of a legend in the motorcycle community, we finally got a perfect policy for the bike! It's now insured at the value we see the bike at, the ID card is marked with "historical" so we can get the right plates, and at a reasonable price. Feels like a home run after a lot of frustration.

Now, it's a matter of trying to get the bike registered and acquire plates for it while the DMV is at a standstill thanks to the Covid-19 shutdown… 

[Drumroll please]…And here is the great reveal! The restored bike is now mechanically reliable with its newly geared starter motor and rebuilt carburetor. The chrome and tank have been polished, and the bike sports newly powder coated side panels.   

There's still some work to be done in due time:

• New ignition (the old one was drilled out so we've been using a screw driver to turn it on and off)
• Right exhaust actually has a hole in it
• Steering lock needs a key cut
• Spokes eventually need to be polished
• Brake has some paint chipped off and exposes rust underneath
• Engine could use some cleaning

In scrutinizing every component to make sure that they work, we've come to appreciate the mechanical simplicity of this bike as well as the Italian engineering. Not always perfect engineering – where we struggled with that starter motor's rarity of the gears, and removing the instrument gauge had us scratching our heads thanks to those oddball plastic nuts that required a special tool. We're pretty pleased with the bike, and ourselves for getting this all done, and in less than a month!

With a motor full of broken gears, we began scouring the internet for a source of replacement parts. Ebay turned up nothing but some random parts and inoperable starter motors. But according to some of the Aermacchi websites, it sounded like the "go-to" person was Ron Lancaster at Lancaster Aermacchi Sprint. We gave him a call and discovered that he sold out of the sets of gears that he had made, without plans for making additional sets. On the other hand, we could buy a new starter conversion built from a Honda Goldwing starter. It would work, but would look like an afterthought on the bike. Not so pretty. Sticklers for keeping the original Sprint 350's details, we kept searching.

05.07.20 Broadening our search to just "Aermacchi NOS Parts," opened up more options for finding the necessary individual components, starting with a set of two ring gears (#50022-73P). We needed only one, so the other one can go back on sale on Ebay one day. We also found a cheap-quality [overpriced!] gear puller on Amazon which helped to pry the broken ring gear out. Baby steps toward making this thing operable.

05.12.20 The Starter Motor Repair Kit (31437-73) arrived! Assuming they must had sold a bunch of these since we've seen a good number of old starters online with broken gear teeth. We promptly removed the cotter pins, pulled out the small planetary gears, and installed them into the Aermacchi – now complete with a full set of new gears. Hopefully, they don't blow up again. Ideally, we'd like to make a set of new, modern gears in a less brittle material to ensure the reliability of our starter. Maybe our talented friends at Additive Restoration can come up with a solution!

And the moment of truth…

We purchased the bike confident that it runs easily with the kickstart. But, like my old '73 Aermacchi Sprint 350, whose the starter motor was temperamental, this one just didn't work.

And so began the methodical process of troubleshooting…

04.24.20 This started with charging the tractor battery that the bike came with, which took about 40 hours to fully charge. The contacts were cleaned as well, so with that variable now out of the equation, we looked to the starter relay. 

04.26.20 We opened up the start relay to discover that it was manufactured by Bosch. Upon inspection, it looked to be in near perfect condition. ​There was some corrosion on the contacts which we removed with some fine grit sandpaper. It was reinstalled onto the bike and with the starter button pushed, we could hear it clicking. It was working like it should! What else could be the problem?

Further along the chain, it was time to inspect the Nippon Denso starter motor itself. We pulled the cover off the starter motor. Brushes looked good. Commutator looked good. Then we pulled the motor out of the housing and inspected each of the pads on it to make sure that there was no crossover current. Everything checked out in the tedious inspection.

So we hooked up the starter motor to the bike, with it out of the housing and it spun. Starter motor works.  

What wasn't working, however, were the planetary gears behind the start motor. The teeth on the gears appear to have been destroyed. Assuming one of the teeth broke off and wreaked havoc, thereby causing damage to the other gear teeth, including the ring gear. What a hot mess.

We received our Special Order Replacement Filter from K&N (SKU: HD-2492). Thank goodness they have a special model specific for the Sprint 350! We sandwiched the filter between the three air box parts and put the unit on the bike. Smooth reinstallation was facilitated by the removal of the carburetor (which is now waiting for a Dellorto gasket kit from Ebay).

Removing the air box the first time – without removing the carburetor – was a major hassle! For a part that needs to be serviced several times a year, they didn't make it easy to access! Maybe that's why people gave up on their HD Aermacchi's in the 70s!

The side panels we stripped were sent down to Texas for powdercoating by an old contact who owns a furniture factory outside of Austin. On the same day that the K&N filter arrived, we received side panels. All the goodies made it feel like Christmas!

The panels got coated in Cardinal BK59, which is a close match to the Rust-Oleum Textured spray paint that we used on the air box…that no one will see! It also comes close in color and texture to the black powder coat used on a Harley Davidson Sportster.

While the instrument cluster is off the bike – we're waiting for a shipment of fork oil before putting the front end back together – it made sense to cut some new gaskets to replace the brittle 47 year old ones.

For the gaskets under the speedo and tach bodies, we sourced a 3/32" fabric reinforced neoprene rubber which matched closest to the original gasket material. Templates were made in Adobe Illustrator with center points for the arcs, and the new gaskets were carefully cut with an X-Acto knife and a circle cutter. 

The original tiny, thin gasket underneath the knurled trip meter was made from a paper thin rubber that had folded on itself. For this gasket, we chose a 1/64" water-resistant lightweight fiber gasket material made from a blend of paper fiber and SBR rubber.

The newly done instrument cluster is ready to go back on the bike!

With the plethora of NOS '73 Sprint brake cables on Ebay going for $15 a piece, and because age and weathering had shredded the original rubber housing containing the electric connectors, it seemed like a good idea to replace the part.

Today was the airbox assembly's turn to get sanded and painted. The original was also rusted, and looked to have the same finish as on the side panels; however, we chose to finish them on our own. Partly because we didn't want to subject it to the vinegar soak. Since it sits underneath the motorcycle seat, it's not a part that will get seen or scrutinized, but nonetheless, it needed some attention.