Service
SERVICE
Gimme a break-in
PAUL DEAN
Q I just purchased a Suzuki B-King that has zero miles on the odometer. I'm very keen on making this bike last for a long time, so I intend to follow the owner's manual's break-in instructions to the letter. The problem, however, is that the owner's manual is not very specific. For example, it says not to run at a steady rpm for prolonged periods of time, but what does "prolonged" mean? Two minutes, two hours, down the street and back? I'm just not sure.
Another question I have is in regard to all the people on the Internet who recommend very aggressive break-in procedures-that is, to run the engine up to redline in each gear, change the oil every 300 miles, etc. The bottom line for me is that information from the manufacturer is pretty vague and information on the Internet seems to contradict what is recommended by the manufacturer. So, what is the best way to break in a motorcycle? Benjamin Johnson Salt Lake City, Utah
A Few subjects have generated more controversy than methods of breaking in a new engine. They run the gamut, from babying the engine as though it were made of fine crystal to hammering it like a racebike from the moment it makes its first spark.
Look at it this way: Who would you rather believe, Internet sources-often nameless and faceless-who have no investment whatsoever in the fate of your motorcycle or the people who designed and built it? If you believe you have a vested interest in seeing that your engine performs without problem, think about the company that not only has to stand behind it if it fails while still under warranty but that also built thousands more just like it?
Because of that latter consideration, the factories tend to be a bit conserva tive in the break-in procedures they publish in their owner's manuals. The combination of modern metallurgy, computerized manufacturing and the latest engine technology results in engines that require much less break-in than they did even a few decades ago.
Most manufacturers would agree that the best break-in technique is common sense. Until the engine has accumulated at least 150-200 miles, don't lug it; that's actually something you should always avoid, regardless of mileage. Don't run it to redline; all the parts that have to seat against one another are happier if higher-rpm operation is held off until they complete that process. Don't ride at a steady rpm any longer than is neces sary; if, for instance, you have to drone along a freeway or Interstate highway, vary your speed by at least 5 mph every few minutes. This helps prevent resonant vibration frequencies, however small and undetectable by the rider, from affecting the break-in process.
And don't baby the engine, either; putt-putting down the road like you're driving Miss Daisy just prolongs breakin. You should run the engine hard enough to create sufficient combus tion pressure to force the piston rings through the oil film on the cylinder walls where the walls have microscopic high spots; this is how the rings seat during break-in. If you ride gently at very low rpm, the rings may not contact the walls with sufficient force to prevent blow-by, which can cause the walls to glaze and perhaps prevent the rings from ever fully seating. But the simple truth is that as long as you avoid any extremes during break-in, the end result-in terms of engine performance, longevity and oil consumption-will most likely offer the most favorable outcome.
Tales of the super-rich
q I have a 2000 Suzuki TL1000R that I bought after it had been wrec ed and left sitting outside in the weather for several years. I replaced the fuel pump, plugs, oil filter, fuel injec tors, battery, all fluids and other small things. Currently, the bike runs but fouls the plugs; the bottom of the plugs turn solid black. White smoke comes out of the exhaust at idle, but when I give it gas, black smoke comes out. When I'm sitting at a red light, the strong exhaust smell burns my eyes, and it gets worse the more I ride. After some repairs by a bike shop, the engine ran better for a couple of days, but now it's doing the same thing again. What could be mak ing it run this way and how can I fix it? Brandon Mckenzie Posted on America Online
A The symptoms you describe are clear indications that the engine is running on an excessively rich fuel/air mixture. When a fuel-injected engine runs this way, it's usually due to one of the injection system's sensors either sending erroneous data to the Engine Control Unit or no data at all. If the problem involves a temperature sensor, the data can make the ECU be lieve that the engine is stone-cold; the ECU responds by delivering a mixture that would be appropriate for start-up and initial running in exceptionally low temperatures but way too rich for normal temps with a warmed engine.
Some injection systems have a "fail-safe" mode in which the ECU reacts to the absence of certain sensor data-or even some data that is outside the range of the ECU'S "map"-by providing a very rich mixture at all rpm, in all gears and at all road speeds. The ECU does this to prevent serious engine damage; otherwise, erroneous data might result in very lean mixtures that could lead to piston seizures, holed pistons and burned valves.
Unfortunately, I don't know if the injection system on a 2000 TL1000R is programmed with a fail-safe mode, and I had no success contacting anyone at Suzuki who could enlighten me. On rare occasions, such problems also
can be the result of a defective ECU; but since your TL-R briefly ran better after repairs by a bike shop, the ECU would seem to be okay. This is why I
think your bike's rich-running problem is most likely caused by either a faulty sensor, a disconnected sensor or a sen sor with a poor connection.
FeedbackLoop
Q After reading the March Service, I want to give Carl Sampson one more thing to check regarding the leaking carburetor on his old CB500 ("Honda pumper carb"). One problem we see fairly often on older Honda carbs is a small lengthwise crack in the brass overflow tub~ inside the float bowl. Here's how to check it: With the bowl off and filled with gas or water, blow compressed air into the tube from the bottom where the overflow hose would connect and you'll see bubbles where the crack is located. We replace the original tubes with brass tubing we buy at a hobby shop. Remove the old tube, measure it, cut the new one to length and epoxy it in place. If the original had the
top rolled over into a small hole, you can create the same thing before installing the new tube by spinning it in a drill and gradually working the brass over. Just wanted to pass this along, as this problem has stumped a lot of people with leaking carbs. Jack Tibbitis Coeur d'Alene, Idaho
A Thank you very much, Jack, for the detailed input. Yours was the first of several letters I received informing me of this common problem with older Honda carburetors. I'm grateful for the enlighten ment, and Mr. Sampson will be even more so if your suggestion ends up rescuing his perpetually leaking carburetor.
The skinny on skinnier
Q I ride a 2003 ZX-12R Kawa saki, which uses a 200mm-wide rear tire. It is getting harder to find replacement tires of this size, so I have been wondering about downsizing to a 190mm rear. I am 60 years old and use my bike as a quick sport-tourer, having equipped it with HeliBars, a Corbin seat and Cargo soft bags. I wonder why I could not install a real sport-touring tire. Any thoughts of stunting, wheelies and track days are far behind me; I'm just looking for a tire with good wear and handling characteristics. Your com ments would be greatly appreciated. Gerry Pelchat Calgary, Alberta, Canada
To detect the suspect device, the bike needs to be subjected to an electronic diagnostic test. Normally, this is a procedure performed by Suzuki dealers who have the requisite diagnostic tester and know how to use it. You didn't state whether or not the aforementioned repairs were done by a Suzuki dealer,
but you might consider taking the bike back to that shop, since the mechanics there apparently had some notion about the cause of the rich running. If they cannot accurately remedy the problem, your next step is to find a Suzuki dealer that can perform the necessary diagnos tic checks.
A The difficulty in finding 200mm rear tires must be specific to your region in Canada, because such tires are readily available in the U.S. From a pure fitment standpoint, mount ing a 190mm rear tire on your Kawa said would be perfectly acceptable. The specified rim width for 190-series rubber is 5.5 or 6 inches, and your ZX-12R has a 6-inch-wide rear rim, so that matchup
is right on the money. And as far as load capacity is concerned, most 190mm sport and sport-touring tires cany the very same load ratings as their 200mm
counterparts or are rated just a few scant pounds lower. How your ZX-12R would handle with a 190mm rear tire is a question I cannot
answer with 100-percent accuracy; I have never tried that particular combma tion and do not know anyone who has. My (hopefully) educated guess is that a top-quality 190 sport-touring tire should work quite well for your less-than amped-up style of riding.
How low can you go?
Q What's the fartl~est that a sport bike can be lowered without affecting its handling? I'm 5-foot-5 and looking to purchase an `09 Suzuki GSX-R750. When I sit on the bike in the showroom, the balls of my feet touch the ground, but I really would prefer to be "flat footed" while sitting on the seat (e.g., at a stoplight). Chris Alleyne West Orange, New Jersey
A Truth is, Chris, that any lower ing of a motorcycle-sportbike or otherwise-will affect the bike's handling. The question is, how much of an effect are you willing to accept?
For a sporthike, first and foremost is the compromise in cornering clear ance, since lowering reduces the degree to which the bike can be leaned over. If you're a trackday addict or like to strafe the backroads, this can seriously handi cap your ability to enjoy those activities. Lowering also reduces the amount of available wheel travel, resulting in a harsher ride. At the rear, any significant reduction in travel changes the swingarm angle, which, in turn, can cause the pull of the chain's upper run during hard acceleration to work against normal rear suspension action. And if the bike is low ered more at one end than the other, the change in front-end geometry can induce unfavorable behavior in the steering.
Despite those possible outcomes, many riders happily exist on slammed bikes of all kinds. They have accepted any handling shortcomings those modi fications have created and see those negatives as a fair exchange for the benefits the lowering has provided.
This is why to lower or not to lower is a decision each rider must make for himself or herself. I can give you some idea of what the effects of lowering a GSX-R750 can be, but I can't tell you if you would find those results ac ceptable. If sitting flat-footed at a stop is more important to you than any of the other changes that lowering might bring about, you'll probably be pleased with the results.
Got a mechanical or technical problem and can't find workable solutions in your area? Or are you eager to learn about a certain aspect of motorcycle design and technology? Maybe we can help. If you think we can, either: 1) Mail a written inquiry, along with your full name, address and phone number, to Cycle World Service, 1499 Monrovia Ave., Newport Beach, CA 92663; 2) fax ft to Paul Dean at 949/631-0651; 3) e-mail it to CWlDean @aol.com; or 4) log onto www.cycleworld.com, click on the "Contact Us" button, select "CW Service" and enter your question. Don't write a 10-page essay, but if you're looking for help in solving a problem, do provide enough information to permit a reasonable diagnosis. include your name if you submit the question electronically. And please understand that due to the enormous volume of inquiries we receive, we cannot guarantee a reply to every question.
