Cycle World Roundup
CYCLE WORLD ROUNDUP
THE RIGHT MIXTURE
Just what a spark plug goes through in the average motorcycle was displayed for the Cycle World staff recently when a crew from Champion Spark Plug Co. drove their portable chassis dyno and computer into our driveway. Fastened onto this dyno was a Yamaha XJ650 and plugged into the Yamaha’s engine were thermocouple spark plugs that transmit temperature information from the tips of the plugs to the computer.
Champion uses this machine to determine spark plug recommendations for motorcycles. Before you can read the chart at the motorcycle dealer that says an N9Y is the correct spark plug for your bike, Champion has taken a bike like yours, fastened it onto the dyno, plugged in different kinds of spark plugs and made temperature readings at various load and engine speed variations. With a portable testing bed like this Champion’s crew can go to all the motorcycle importers or manufacturers and test the bikes when they are first introduced, providing information for the bike owner as early as possible.
What was most interesting in the demonstration was watching the temperature effects of changes in tuning. With the Yamaha set to factory specs and normal 'N7Y plugs installed, plug temperatures ranged from around 500° at idle up to around 1400° with the throttle wide open and load adjusted so the bike would have been running about 90 mph. These numbers may sound outrageous, but they are normal temperatures that a spark plug experiences in regular operation and they can run under conditions like this for thousands of miles. Problems begin when plug temperature goes below 500° or above 1600“.
When the timing was advanced slightly and one carb was put out of synchronization with the others, the difference was most pronounced at low engine speeds where the one cylinder could run noticeably lower intake vacuum. At 2500 rpm, or 30 mph, the harder working cylinder was at 920° while the others were around 700°. As the load increased the difference ^arrowed because the other carbs began pulling at full volumetric efficiency, too. The advanced spark increased maximum plug temperature to around 1600°, near the maximum safe temperature.
With the load increased 10 percent at all speeds spark plug temperature went up about 100° at low engine speeds and about 200 ° at 90 mph, to the 1600 ° range, even with the timing and carburetors adjusted correctly.
As a finale the Yamaha received a colder plug in one cylinder and a hotter plug in another cylinder, plus two correct plugs in the middle. At 30 mph the colder plug was running 440°, within the fouling temperature range, while the average plugs were running 575° and the hot plug ran 980°. The test cycle wasn’t taken up to 90 mph because the hot plug was getting too hot. At 70 mph, or 5600 rpm, the cold plug was 1060°, the average plugs were 1270° and the hot plug was at 1850°, a temperature that can put small aluminum particles on spark plugs and tiny windows in pistons.
During discussions with the technicians, several questions were answered that might be of interest. People change spark plugs when their bikes aren’t running right, the Champion people said, but the plugs are usually not the cause of the problem, only a symptom. If a stock bike is fouling plugs, for instance, it is generally not a sign of too cold a spark plug, but incorrect carburetion, providing the stock spark plugs are installed.
If you’ve hopped up your bike, you might need a slightly colder plug, but it’s better to adjust carburetion around a heat range only slightly colder than standard. Don’t put plugs three heat ranges colder in the bike and then change jetting to match the plugs. Better to go maybe one range colder and jet for that. Avoid using a hotter heat range plug unless the carburetion has been checked out and the plugs show obvious signs of fouling. Hard starting after a tuneup or installation of fresh plugs might be traced to incorrect plug gap. Now that more machines are coming equipped with more powerful ignitions, spark plug gaps have widened on many applications, so a bike with a less powerful ignition might need plugs gapped not as wide as some plugs come.
Champion’s dyno is a wonderful tool. There’s lots of information available from it, but unfortunately it isn’t something that we have access to or even race teams can use. Occasionally, however, it is demonstrated at motorcycle rallies. If it’s in your area, go take a look at it. It’s fascinating.
NOBODY LISTENING
When Congress looked at budgets last year and saw that the Department of Transportation was planning on spending more money on the same programs it had always spent money on, getting little in results, congressmen decided to change things a bit. The budget was sent back to DOT and the bureaucrats were told to ask the public for comments on where the money should be spent.
Motorcyclists, more than any other group of people, took this breath of fresh air to heart and wrote letters to the government suggesting things that could be done to improve highway safety. Over half of the comments received came from motorcyclists and the motorcyclists had good ideas. They suggested licensing improvements, rider training, share the road projects, voluntary helmet use campaigns and improved data systems. To support these ideas they sent information on experimental programs that supported the suggestions. After all, when the announcement was printed in the Federal Register asking for suggestions, it said the ideas would be based upon proven effectiveness and significant potential and empirical experience. All these things were provided.
Now the DOT has written its amended budget and sent it to Congress, after having reviewed 650 suggestions. Not surprisingly the new budget request looks just like the last budget request, except that a voluntary seat belt use campaign has been added. No motorcycle safety programs have been included. DOT has a reason for that. After asking for suggestions on where the money should be spent, DOT added its own criterion to evaluate the suggestions. That criterion was past funding. What the DOT was looking for was programs already receiving money that could be continued.
Motorcycle safety projects have never been of much interest to DOT except for mandatory helmet laws, w hich didn’t cost much. As a result, about 1 percent of DOT’s funds have been spent on motorcycle safety projects, even though motorcycles comprise about 4 percent of the traffic flow' and 10 percent of the nation's highway fatalities.
And as a result of that, i.e. no funds for programs that aren't already funded, motorcycles get nothing, while all those who took the trouble to comment learn how' much their input is w'orth.
TWO WHEEL DRIVE
ost likely the Rokon Mototractor is the strangest motorcycle made. It has two tractor-like tires, both of which are driven by a Chrysler 134cc two-stroke Single through a collection of torque converter. gears, shaft and chains. For a while the Rokon seemed to disappear, but now the good news is that Rokon is alive and well, living in New Hampshire. A group of New Hampshire businessmen have purchased the patent rights to the Rokon and they are setting up manufacturing facili-
ties in Jaffrey, New Hampshire.
Two models are in production, the Ranger with sealed wheel hubs for floatation and the Scout with spoke wheels^ Equipped with its power takeoff, the Rokon is adapted for fire fighting or generator connections or spreading seed. Its speeds range from a half mph to 40. interested explorers can contact Rokon at RO. Box 427, Route 202 North, Jaffrey, N.H. 03452.
CHARITY RALLY
The proper name is the Charity Begins At Home Rally IF the cause is Muscular Dystrophy, the date is June 26 and¿ the place is somewhere in Nassau County, N.Y.
“Somewhere” has a vague sound to it but at press time the rally sponsors didn't have the exact site pinned down.
The other details are clear. Last year some motorcyclist enthusiasts decided was time to have a gathering of riders in' the northeast. So they had an all-day ride plus raffles. They sold tickets and raised $8000. A success, which means they'll have another rally this year.
Grand marshals will be Craig Vetter, Malcolm Forbes and Billy Joel. The day will begin with a ride around Long Island then three shorter rides led by one of the three marshals, then the raffles, riding seminars and such. Tickets, for which you get chances in the raffles and a chance to tell Vetter about fairings, Forbes about money and Joel about music, are $10. For more details, call (516) 741-2010, be?? tween 7 a.m. and 4:30 p.m. Monday through Friday.
FREE AGAIN
Seldom does the Anti-Destination League lose a battle, but this time the League has taken it in the shorts. In our last episode, you will recall, the ADL had encouraged the National Highway Traffic Safety Administration to make lots of stupid rules about speedometers. Speedometers couldn’t read higher than 85 mph, NHTSA ruled, and a highlighted 55 had to be marked to encourage slow driving. Also, more numbers had to be added so drivers would know if they were going 100 kph or 60 mph.
In a stunning blow against absurdity, the N HTSA has abandoned its speedometer rules. As of March 25 the limits on maximum speed, the requirement for the big 55 and the double unit requirements were dropped. Also, a requirement for tamper-proof designs that would have gone into effect this September was thrown out. In this reversal of policy, the new leaders at NHTSA said that there were no indications the speedometer rules had done anything to increase safety or slow drivers. It also said the rules added to the costs of vehicles. Most of the major auto companies have pledged to continue producing vehicles with only 85 mph speedometers, but the smaller manufacturers will now be able to revert to more normal speedometers. At least when the supplies of 85 mph speedometers are depleted, there may be a change.
SAFETY SUCCESS
■ood things are going on in Washington state for motorcyclists who want to learn to ride or learn to be better riders. The state Traffic Safety Commission now has a toll free 24-hour a day phone line providing information on the rider education programs around the state. By dialing 1-800-562-5505 Washington motorcyclists can find out about locally sponsored motorcycle training courses in 14 counties. Both the Motorcycle Rider Course and the Better Biking Program are MSF-approved courses.
Perhaps the program is having an effect. In 1981 there were 3796 motorcycle accidents in Washington, down from 3985 the previous year. Helmet use is up 19 percent. Something is working.
OFF-ROAD ATLAS
Finding good ofT-road riding areas has just become easier. The American Motorcyclist Association is now publishing AMA 's Trail Riding in America, a 128 page atlas of off-road riding areas. The $4.95 book, available through motorcycle dealerships, consists mostly of maps of riding areas. The listings cover 255 BLM resource areas, 200 state, county, local, private and Corps of Engineers areas and 200 individual inset maps. Another 500 areas where recreational trail riding is permitted are also shown.
In addition to all the maps, there is information on where to go for information, who to call, how to get to the riding areas, when the riding areas are open and state laws affecting the trail rider.
THE 200 MPG CLUB
espite the advertisements for 200 mpg carburetors, there are few members of the 200 mpg club. There are none, in fact, in the Craig Vetter Fuel Economy Run. Your chance to join is coming up soon.
The second annual Craig Vetter economy run will be held July 10. Entrants will leave the Madonna Inn at the south end of San Luis Obispo, California and head up the coast in time to watch the races at Laguna Seca. Registration begins at 6:30 a.m. This year there is some money to be made. The highest mileage private entrant ^gets $600. A $300 prize goes to the highest mileage Honda, Yamaha, Kawasaki, and Suzuki over 750cc, and $300 goes to the best of each brand from 500 to 750cc. There’s another $300 for the best Harley, $300 for the best of all other brands over 500cc and another $300 for the best other yorand under 500cc, plus $300 for the highest mileage obtained with a bike equipped with a Vetter fairing.
This year there are rules for the run, things having to do with being refilled with the same kind of gas started with, private entries being street legal, no towing, drafting, pushing etc. In the Industry class it boils down to using the least cost of energy and getting away with it on the public roads. This is to encourage alternate energy sources. A bonus is provided for carrying a passenger.
If a private entrant looks too radical, Chief Judge and Jury Craig Vetter may bump it up to the Industry class. There is no money paid to the winner of the Industry class. Instead, there is a perpetual trophy, a great giant of a trophy, with a metal sculpture of a fuel economy special.
For the past year the Industry trophy has been at Cycle World after being won with a Honda Passport. This year we’re getting serious about winning. No effort will be spared, no expense will be too great. We’re out to join the 200 mpg club.
