This beautiful blue 1973 Harley-Davidson® FLH was brought to us equipped with a hand shifter which was added at some point in it’s history and not a factory setup. The customer requested that we convert it back to a foot shifter. We suspect this was requested for both comfort and retaining period correctness. The motorcycle was also smoking from the rear cylinder and we were to remedy this as well as a short list of other repairs.
After tearing down the rear cylinder head, we discovered the smoking was due to a valve seal that had come off of the valve stem. This allowed oil to travel from the rocker box into the combustion chamber. The combustion chamber is where the spark ignites the fuel, so when the oil traveled through the valve stem into the chamber, it would burn- creating smoke.
To repair the valve seal, we had to remove the valve springs and trim a small amount of material off the valve stem to allow more clearance for the valve spring and retainer. We then purchased several different styles of seals to determine which would be the best fit. There were a few different styles and manufacturers to choose from and we wanted to ensure the best fit possible.
After selecting the appropriate seal we installed it using a Loctite® product designed for bearing and seals, called Bearing Mount 620. This green goo with its syrup-like consistency acts as a glue or bonding agent to prevent the two pieces of metal from separating. We reinstalled the heads on the motor and were pleased to find that the smoking symptom had been fully cured.
The customer had also requested new tires that looked more time period correct, so we installed a set of Shinko Classic 240’s, which offer modern construction and performance in a classic design.
Another concern we were to address was the camshaft. The customer indicated that it had a camshaft in the engine designed for higher RPM performance, and did not intend to run the motor that hard on a regular basis to utilize the cam’s performance. We installed a S&S Cycle 450S grind cam which is designed for low and mid range RPM- a more practical cam for a day-to-day riding application.
Our final work involved a simple carburetor cleaning, as the motorcycle had been sitting for an extended period of time. Also due to lack of use, the brakes required some attention. We dissembled and thoroughly cleaned the master cylinder and caliper, then reassembled and bled the brake. This successfully remedied the front brake sticking.
We hope the owner is as satisfied as we are with the work completed on this beautiful bike!
