Purchasing a vintage motorcycle that hasn’t ran for many years is a big decision and getting it roadworthy again is a journey that takes commitment and work. A customer recently brought in this 1967 Harley-Davidson Shovelhead that had not been started since the ’80’s. It’s had the same original owner for the last 55 years. We always admire those who hold onto at least one of their bikes the majority of their lives. Many share stories of ones they wish they hadn’t ever let go of and too few tales of keeping them as long as they’d hoped.
As you can imagine, a bike that has sat for ~40 years often requires a great deal of effort to revive. One of the first things to check is if the interior of the gas tank shows signs of rust or old, stale fuel. Gasoline has a surprisingly short shelf life and can go bad within mere months. If your tank is full of rust, drain the old gas and flush with vinegar. As they are often clogged with rust, replace the old petcock when necessary. If your tank requires extensive work, check out a helpful article on getting it restored here.
After ensuring that the fuel tank is operational, the next step is to clean and clear all passages and jets in the carburetor. The early Harley-Davidson “butterfly” carburetor offers a simplistic design and our ultrasonic cleaner was able to quickly clean it. If access to an ultrasonic cleaner isn’t available, an alternative method is using carburetor cleaner and a small wire to blow/push through the jets and verify they’re properly cleaned. Especially on older motorcycles, we recommend installing a fuel filter to catch any small amount of debris. This is crucial to prevent contaminants from getting into the carburetor.
On any machine that has been sitting untouched, a thorough assessment of regular maintenance items is key in getting it roadworthy again. The primary items to address are the spark plugs, ignition points, oil/filter, drive chain, and of course, tires! The Shovelhead was serviced with new Auto Lite spark plugs, the ignition points were cleaned with a file, and the points were re-gapped. Following these steps, it produced a nice, blue spark!
As with any motorcycle, always check your oil. If it is low, replenish to the fill mark and then perform a complete oil and filter change once it’s running. On motorcycles with a “dry sump” oil system, like Harley-Davidsons, some are surprised to find the oil tank completely empty after it has been sitting for some time. This is the result of the check valve in the oil pump allowing oil to leak from the tank into the engine cases. This produces an event called “wet sumping”: check out the video here. Although alarming to owners who’ve never experienced it before, it commonly occurs in machines with these systems that have sat for an extended period of time.
TIP: Countless customers find their oil tanks empty and fill them with more oil prior to running, not realizing that it has wet sumped and filled the motor with oil. As soon as the bike is started, that oil is pushed back into the tank, which is now full and therefore cannot not accept it. This pressure causes oil caps to shoot out and oil to violently escape. Although it goes without saying that you never want to run your bike without any oil, ensure wet sumping isn’t at play before adding more oil and creating an even bigger mess!
With a clean fuel system and good spark, the next phase usually involves getting the bike to run. When old kickstart motorcycles are involved, it’s common for it to become a bit of a competition here at the shop to see who can get it started. Per usual, Dain was the first to find success with the Shovelhead, as captured here. Sometimes, the diagnostic process will reveal the reason that a motorcycle was originally parked. After many years, the issue the bike was having is often long forgotten. For that reason, we always give new intakes a thorough check through, making sure that they don’t have any strange noises, the motorcycle shifts through all the gears, and that all systems are functioning properly.
Once started and running, it’s important to assess if the motorcycle is capable of charging the battery. Luckily, the original generator worked, but on vintage Harley’s in particular, we recommend upgrading to a Cycle Electric Generator. They offer a “self-contained” voltage regulator that only requires 3 wires to install. This offers the Shovelhead’s owner confidence for many years to come that issues with charging are highly unlikely.
After sitting untouched for years, tires develop flat spots and dry rot from the rubber getting old and brittle. This makes them too unsafe to even consider salvaging and we always recommend new tires on projects of this nature. The customer requested modern replica tires, so we installed a set of classic Shinko 240 double whitewall tires. Shinko has been increasingly producing “vintage” style tires that are well-suited for antique bikes by offering similar aesthetics of the period at an affordable price point.
Another common issue with vintage Harley’s is the main drive seal on the transmission leaking, either due to age or the sprocket coming loose. Unfortunately, this Shovelhead was leaking profusely! Harley did not change the design of this seal from 1936 until 1979, so we actually had it in stock. This is true with many vintage Harley parts, which makes sourcing these parts easier. Given their popularity, vintage Harley’s also have extensive aftermarket part offerings. A transmission oil leak while on the side stand is a common symptom of a bad transmission drive seal. We replaced the seal and ran a small bead of silicone around it to ensure it won’t leak.As with any old motorcycle, it’s important to keep up on maintenance for them to be reliable. This includes greasing all bearings, lubricating pivot points, checking for loose bolts periodically, adjusting valves, and changing the fluids regularly.
As with any old motorcycle, it’s important to keep up on maintenance for them to be reliable. This includes greasing all bearings, lubricating pivot points, checking for loose bolts periodically, adjusting valves, and changing the fluids regularly.
If you have the desire to own and ride a vintage motorcycle, be prepared to truly get to know your motorcycle and put a lot of work into it. Some vintage motorcycles are certainly easier than others, but they all require work. For many, this effort is worth it and can be a very rewarding experience that in the end offers the rider better understanding of their motorcycle as a whole.
The Shovelhead‘s owner is thrilled to have the motorcycle they’ve owned since they were only 16 years old back in running condition!
