So I was looking for an origin of the term 'Clubman Bars', but couldn't find one. We'll just have to make up our own history for them I guess. Regardless of their naming origin they are de rigueur for cafe racers. And so I started to put back on the controls this evening. The OEM throttle grip core had to be modified so that I could mount the lovely aluminum bars ends I bought from Dime City Cycles.
The café racer is a light and lightly powered motorcycle that has been modified for speed and handling rather than comfort. The bodywork and control layout of a café racer typically mimicked the style of a contemporary Grand Prix roadracer, featuring an elongated fuel tank, often with dents to allow the rider's knees to grip the tank, low slung racing handlebars, and a single-person, elongated, humped seat.
One signature trait were low, narrow handlebars that allowed the rider to "tuck in" — a posture with reduced wind resistance and better control. These handlebars, known as "clip-ons" (two-piece bars that bolt directly to each fork tube), "clubmans" or "ace bars" (one piece bars that attach to the standard mounting location but drop down and forward). The ergonomics resulting from low bars and the rearward seat often required "rearsets", or rear-set footrests and foot controls, again typical of racing motorcycles of the era. Distinctive half or full race-style fairings were sometimes mounted to the forks or frame.
The bikes had a utilitarian, stripped-down appearance, engines tuned for maximum speed and lean, light road handling. The well-known example was "The Triton", a homemade combination of Norton Featherbed frame and Triumph Bonneville engine. It used a common and fast racing engine combined with a well-handling frame, the Featherbed frame by Norton Motorcycles. Those with less money could opt for a "Tribsa"—the Triumph engine in a BSA frame. Other combinations such as the "Norvin" (a Vincent V-Twin engine in a Featherbed frame) and racing frames by Rickman or Seeley were also adopted for road use.
A 7/8" hole saw fits perfectly, as it should, since the diameter of these bars are 7/8". Once that was drilled out, the plastic could be cleaned up a bit with a craft knife, then it rotated very easily once back on the bar. Getting the new handlebar grip on was easier than I thought, but still required some serious effort. With a little dash of WD40, things progressed a lot easier. It's really just a question of slowly working the rubber over the tube, moving from top to bottom, in a caterpillar type movement. The replacement grip does not quite match the profile of the OEM grip, so there is a little piece of the throttle body still showing. I will most likely peel back the rubber grip and spray this flat back.
The repainted kill switch looks pretty good. I was concerned that I had layered the paint on too heavily, but it dried out okay. The kill/starter switch assembly has a small metal tab that internally locates in a hole in the OEM handlebars, so I had to measure and drill a new set of those. I angled the switches towards the rider so that they are more comfortable than the OEM position. The clubman bars do put you in an aggressive riding position so whatever you can do to make the ergonomics easier on the wrists is always a good idea.
Before I mounted the switchgear permanently I had to install the new mirrors. These are machined to fit 1" diameter bars but come with hard plastic spacers to increase the diameter of your 7/8" bars. I found the spacers to be slightly on the small size and even with tightening the mirrors as much as I could they weren't snug enough. With some thin gauge (0.016") aluminum flat bar from Lowes I could shim them out to a super tight fit. In an ideal world (like this time next year in my new workshop) I would be able to turn down a piece of aluminum in a lathe and make the exactly right diameter spacer, but this solution will do.
Technically these are bar end mirrors, so they should be mounted on the extremities of the bars, but both myself and the bike's intended rider are skinny as rails, so I can position them where they are now and still be effective: A larger rider would have a good view of only their sides while riding.
I still have to mount the left hand grip, but that requires some frictionless assistance, and a common product used to mount grips is actually hair spray. It allows the grip to slide on but then turns to a sticky goo after a few days and the grip is pretty much on forever. So a trip to Walgreens is in order tonight.
Current hours on build: 149.0