From The Field
Harley-Davidson Museum Trip By Gene Walker
My wife and I flew into St.
Louis, Missouri, then drove up to Milwaukee, Wisconsin to
Harley-Davidson's new museum dedicated in 2008 to celebrate their 105th
We had registered in advance to get in the first guided tour at 10:00 am that would last about 45 minutes. The next 6 hours were spent admiring all the excellent displays, reading posters and taking pictures. We had lunch in the H-D Motor Restaurant. Conveniently next door was the gift shop where we had to pick up a few souvenirs because most items were only available there.
While in the competition area, we found a hill climb poster from Rocky Butte in Portland, Oregon and also one from Lewiston, Idaho, both from the early 1940's. Some of the other highlights were:
Seeing the very first motorcycle built in a 10x15 shed in 1903 - Serial #1.
One of only 27 1909 first V-Twin engine models.
Their first 3-speed transmission built in 1915.
The 1936 61-cubic inch streamliner that Joe Patral rode to a world speed record of 137 mph at Daytona Beach Florida in 1937.
Numerous racers featuring an actual size portion of wooden motor-drome track including period race bikes.
All sizes of bicycles from the teens to early 1920s.
Numerous shapes and sizes of commercially made vehicles.
Various military models built for the government during World War II.
The actual 1956 KH model that Elvis Presley bought in Memphis, Tennessee.
Peter Fonda's & Dennis Hopper's motorcycles from the movie Easy Rider.
Numerous glass display cases with enormous amounts of vintage memorabilia
A huge wall display of beautifully painted gas tanks dating from 1930 to present.
It was so inspiring walking down a time capsule forming a train of motorcycles spanning over 100 years of continuous production.
By Bjorn Klingenberg
by Melissa Becker of Chris Becker in a Mountain Trucking Co. Tanker
Truck in 2001
Photo by Melissa Becker of Chris Becker in a Mountain Trucking Co. Tanker Truck in 2001
Just like “real” cowboys don’t use seatbelts in their pick-up trucks, “real” truck drivers don’t use the clutch. It takes a certain skill and is not as easy as one might think. Those of you who own vintage vehicles can practice on your un-synchronized, or partially un-synchronized, transmissions. Manufacturers of heavy duty transmissions, such as Fuller, prescribe double clutching as a precaution for all shifting of their manual transmissions. Today, many heavy duty transmissions are partially automated.
Actually, changing gear is a misnomer since gears, contrary to the early days of the automobile, are no longer changed at all, but are in constant mesh in pairs. The dynamic factors influencing the “changing of gears” in any gear type transmission are:
Vehicle gross weight
Vehicle aerodynamic drag
Vehicle rolling resistance
Internal friction in axels and power train
Internal friction in the gearbox
The forward power and reverse braking of the engine and when fitted, engine or driveline brakes.
Shifting a transmission can be facilitated by the use of a clutch and by the manufacturer incorporating synchromeshed gears, gear dogs and gear synchronizers. Functionally, such devices are not necessary, except for a clutch when starting a vehicle. Operating a vehicle without using a clutch, particularly a heavy duty truck and its power train, takes constant awareness of the road grade ahead and good coordination of all faculties. A tachometer is invaluable as are the proper steps in the transmission.
Up-shifting on level road: When engine speed reaches a point where it is desirable to select a higher gear, the shifter can be moved into neutral by letting off on the throttle. As engine speed drops, the force on the gears is reversed from being asserted by the engine to being asserted by the inertia of the truck slowing down. At that precise point the shifter can be moved into neutral without any difficulty.
As engine speed continues to drop, now at a faster rate with the transmission in neutral, the transmission input shaft reaches synchronous speed with the output shaft. At that point the shifter can be moved to a higher gear without any difficulty.
Up-shifting uphill: The same conditions apply as on level road except that the time before the shifter must be moved to engage the higher gear is shorter due to the faster slowing of the vehicle and the speed of the transmission output shaft. A condition is that the right speed of the engine is obtained before the comparable maximum speed of the output shaft. An engine exhaust brake may facilitate this or be required to accomplish it.
Up-shifting downhill: When going downhill, the time before the shifter must be moved is longer than on level road due to the increasing speed of the vehicle and the output shaft. If the effect of gravity on the road speed exceeds that of the inertia of the vehicle it may be necessary to briefly apply the foundation brakes.
Down-shifting on level road: The reason for down-shifting on level road is to provide engine braking or to increase acceleration. Neutral is engaged as described above but engaging a lower gear requires using the throttle to increase the speed of the engine and the transmission input shaft to match the speed of the output shaft.
Down-shifting uphill: Down-shifting is often necessary to negotiate a gradient. As on level road engine speed must be increased to select the lower gear, but less so due to the faster slowing of the vehicle and the speed of the output shaft.
Down-shifting downhill: The prime reason for down-shifting on a downhill is to provide sufficient engine braking to maintain vehicle control without excessive use of the foundation brakes. This requires proper assessment of the grade ahead. Due to the effect of gravity and the increasing speed of the vehicle and output shaft, the time for shifting to a lower gear is much shorter than on the level depending on the grade. If the driver misses the critical point allowing the speed of the output shaft to exceed the maximum engine speed in the required lower gear, the vehicle must be slowed down using the foundation brakes. If the brakes fade the only recourse is to find the nearest escape ramp. Consequently, the proper vehicle speed and gear for a grade must be selected and engaged before beginning the downhill.