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| Chain maintenance during a long-distance touring is a daily chore. Chain sagging occurs after kinks are observed in chain links. |
We rode under various weathers, from 5 to 40 degrees C, from monsoon rain to hot sunshine. The coldest riding days were in Southern Alberta and around Glacier National Park, Montana, while the hottest riding days were in Texas and Louisiana. We experienced monsoon rain in Metairie, just west off New Orleans, and the best riding conditions (25 degrees C, still air, sunshine) in New Mexico - Texas border and Southern Utah.
My motorcycle is BMW F700GS, which has an 800 cc engine, a maximum rated 75 hp power at 7300 rpm, and a maximum rated 77 Nm torque at 5300 rpm. The maximum payload it can have is 227 kg, so our payload is close to the maximum allowed. My average highway speed is 70 mph (112 km/h) during the trip, which was 1/3 of the time felt inadequate, especially on interstate highways that have 80 mph speed limit. I can push my motorcycle to 150 km/h (94 mph) when overtaking trucks or RVs, but it's having a hard time sustaining a 75 mph average speed or higher with our payload in order to keep up with fast-moving interstate highway traffic. The maximum 0.18 hp per kg of total mass (both payload and motorcycle's mass of 200 kg) proves 1/3 of the time inadequate.
The horsepower per kg (i.e., power to weight ratio) is a good measure to use as it factors in motorcycle's mass, payload, and power output. For example, if I ride by myself, the figure of merit changes to 0.25 hp per kg, representing a 38% improvement over a two-up. Because drag force only depends on surface area, which is constant regardless whether it is a solo or a two-up, and speed, then I expect to be able reach an 80 mph average speed when I am riding solo.
The only solution to improve the 0.18 hp/kg number is to change a motorcycle with a larger engine displacement. The larger hp/kg requirement doesn't mean that sports bikes, like BMW S1000RR, are good choices. Even though S1000RR has a 0.48 hp/kg power to weight ratio, which is a fantastic improvement over my F700GS, it doesn't have the correct riding posture for a multi-day touring. The upright riding posture of the BMW GS models fits best for the multi-day touring. My back and arms didn't feel sore at all after straight 7 days of riding, covering 4500 km. Other adventure touring motorcycles, such as Yamaha Super Tenere and Suzuki Strom, will fit best too.
Beside power-to-weight ratio and riding ergonomics, I find power transmission drive type matters as well. The chain drive of F700GS requires daily maintenance because I cover about 620 km every day. (Normally, chain links need to be cleaned and lubricated every 500 km.) I had to clean and lubricate the chain in the morning before we rode. Because we do 8-10 hours of riding, we're tired by the day's end, and the morning cleaning ritual works well. My motorcycle chain was stretched at the end of our trip (see photo). Next time I will have to bring a spare chain and rear sprocket pair for such long distance touring.
Shaft power transmission drive will not require daily maintenance and in my opinion is the ideal drive type for a long-distance touring. Some adventure touring motorcycles, even Honda Africa Twin CRF1000L, have chain drive; although chain drive is lighter, I have to wonder whether the rigor of chain drive maintenance might interfere with the trip enjoyment. I know it did in my case. My left thumb was almost crushed by the rear sprocket when I was cleaning it.
After power-to-weight ratio, riding ergonomics, and power transmission drive type, the fourth requirement is wind (rain) protection. During our trip, we experienced high crosswinds in Texas - New Mexico border along I-40 and in Highway 2 around Cardston, Alberta. A tall front windshield will remove most of the wind problems. When I started riding 2 years ago, wind protection was my main concern, but as I get used to handling crosswind forces, I now think that the tall windshield is good enough. A full fairing that protects the entire arms, body, and legs is better of course, but it's not necessary since quite often rain doesn't occur throughout the trip. I find that rain does occur within 10-15% of the time.
The most important requirement is in fact riding ergonomics. Fatigue and soreness in arms and back are no option for riders going long distance. That's why I hesitate if I should ride Yamaha FJR1300 even though it satisfies power-to-weight ratio to give an 80 mph speed average, power transmission drive type, and wind protection. FJR1300 riding posture is bending forward, more sports-bike. One other factor, though optional, is the off-road capability. I like F700GS because it allows me to ride on gravel roads to a campground or a hiking trail. I didn't have this experience in our New Orleans trip, but it occured in previous trips.
The next important requirement is power transmission type. Chain maintenance requires 1 hour per day and requires one to carry chain cleaning and lubrication tubes, in addition to spare chain and sprocket. This may actually be acceptable for some riders who ride around the world and value easy repair of chain drive. I happen to think, however, that shaft drive is better. My next motorcycle will have to have a shaft drive.
Power-to-weight ratio is the third important requirement. F700GS is actually fine power wise if I don't mind with a 70 mph average speed. It will still take me where ever I want to go. If I encounter a faster speed limit in a highway, I simply exit it and use a secondary highway. The power-to-weight ratio is an ego thing - somewhat.
The touring thinking I outline could explain why BMW R1200GS is so popular. I would like to have such machine, but it's so expensive. Yamaha Super Tenere offers much more reasonable price and arguably better reliability. That's a decision process I have to go through.
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