The XLR-TT came on the scene in 1958 and stayed in production until 1969, and is one of the rarer
members of the extended Harley-Davidson Sportster family. Depending on which historian you
subscribe to, there were between 200 and 500 XLRs made. Despite looking like a stripped XL Sportster,
these were pure racebikes with no provision for lighting or other street amenities.

In which kind of competition did XLR-TTs partake? As the name suggests, TT events with their dirt
turns, left and right, and jumps were a natural. But because the 883cc V-twin was too big for AMA
national-class races, the bikes ran in the unlimited open class or at so-called outlaw races that ignored
AMA etiquette. Despite weighing 350 pounds, many XLRs ended up on scrambles tracks, precursor to
motocross. Others slogged through the rocks and roots and rivers of enduro courses. Some sprouted
fairings and sticky tires and went apex hunting, notably the late Lance Weil who took an XLR-based
roadracer to England and showed the tea-and-crumpet crowd than Yank riders knew how to do more
put a foot down and turn left. Other XLRs – or parts of them – went nitro drag racing, and there was an
XLR-based engine, albeit heavily reworked, in the Harley streamliner that took Cal Rayborn to a 265.492-
mph world record in 1970.

The XLR's performance came from its engine spec. While run-of-the-mill Sportsters went out into the
world with their cams running in needle bearings and bushes, XLRs benefitted from friction-reducing ball
bearings. Likewise, their crankshafts ran in roller bearings. The bikes had specific flywheels, pistons and
connecting rods. Different cylinder-head castings allowed larger valves and a bumped-up compression
ratio. Hotter cams were installed as well as a lightened valvetrain. Ignition was via magneto, moved
from the right side of the engine to a tucked-up position ahead of the front cylinder. Even the XLR
frames were special, built with a better grade of steel so the walls could be thinner and the whole
assembly lighter.

This particular XLR-TT is one of 30 built in 1964. It is equipped with most of its original equipment,
including some special factory parts like an aluminum rear fender and brackets, a Daytona-spec 8½-inch
alloy front brake and Heco shocks.