Originally Posted by tcs
I'm no expert, but let's see...
Standardized controls are a fairly new thing in motorcycling, having come about really only in the last 40 years or so and still not totally universal worldwide.
These very old bikes will typically have a clutch, which could be as simple as a belt tensioning roller, usually worked by a hand lever. It's not spring loaded like modern clutches; push the clutch lever in and it will stay when you take your hand off. The throttle is probably a twist grip even from the earliest days, but you might not notice it in pictures because the cables were often run inside the handlebar tube. Some very old bikes will have an amazing system of external linkages instead of hidden cables! That throttle was probably on the right grip (most folks have right master hands) but not always. Then you'll need a spark advance lever, a compression release lever, a shift lever (well, if your bike has a multi-gear transmission, which came around 1910-1912 for most makes), and of course a lever on the oil pump for the rider to lubricate the top end. Then there'll be a kill switch, perhaps a muffler cut out lever, and, so the rider's feet didn't feel completely left out of the riding experience, a foot lever for the rear (only!) brake.
All these bikes will have unique features, but in general to get underway: put the bike up on the (center) stand, open the kill switch and petcock, tickle the carb, give the oil pump a few strokes, set the spark advance, open the compression release, disengage the clutch, select the best gear for starting, engage the clutch, put your hand on the throttle and then begin to pedal. As the engine begins to spin, close the compression release, carefully give it some gas and - voila - the engine began to fire. Quit pedaling, engage the clutch, tap the brake to stop the rear wheel from spinning, get the bike down off the stand, select first gear, tweak the spark advance, give the oil pump another stroke, disengage the clutch as you give it some gas and ride away.
Perfection! What could be simpler?
That's fairly good, but a few items need clarification. Very few of those bikes have a CLUTCH! The Harleys, the Indians, the v-twin AJS, the Morgan, and possibly another 3-wheeler; otherwise, it's direct drive via belt from the crankshaft to the rear wheel - single speed, no clutch.
If you want to stop, you kill the engine using the valve lifter lever (which lifts the exhaust valve a little bit off the seat, and the engine loses compression). Brakes are terrible; usually a bicycle-type stirrup on the front wheel, and a 'dummy rim' on the back, which you press a pad of friction material against a rim beside the tire (like a carriage). Throttles as we know them weren't invented until the late 20's, and most of these bikes use two-lever carbs; one lever controls the throttle slide (so far so good), the other raises and lowers the main jet, controlling the fuel intake (I lost you there, I know - it's really a pain at first, but becomes second nature after a while).
Gearboxes didn't come into vogue until the early 20's, although some advanced marques used them in the 'teens (H-D/Indian, Sunbeam, etc). The American manufacturers were amazingly ahead of the curve until the late 1920's, and built the fastest and most robust bikes in the world. What happened after that is a long story, but I can tell you, a 1915 Harley is a FAST motorcycle for the day. Some modest tuning will see near 100mph on a bike with no brakes or suspension to speak of.
I know the fellows with the 'original paint' H-D and Indians pictured, they certainly are aware of how special these survivors are. Amazing bikes.
The event is organized by the VMCC in England (Vintage Motor Cycle Club). It's not easy riding a bike with no clutch or brakes in modern traffic.... These are great photos, thanks!
If you want more pix and talk about old bikes, visit my blog;