Service
Service
SAVAGE THIRST -> ASK I(EVIN -> SLOBBERING HOG
RAY NIERLICH
DASTARDLY OIL?
Q: I read the letter in the Jan./Feb. issue regarding automotive oils in motorcycles. Will I be creating a problem using Castrol GTX 10w-40 in my 1998 Cold Wing instead of the more expensive Honda oil?
A.M. COMITE PORT CHARLOTTE, FL
A: You will probably never have a problem. Cold Wings are bulletproof. That said, what is with taking the chance of frying the clutch just so you save a couple of bucks? Some less-than-bulletproof bikes have experienced problems with starter drives slipping ($$$) as well as clutch slip and, worse yet, camshaft failures. Oil at my local Honda dealer runs about the same price as auto oils. You certainly can use Honda oil, but you don’t have to. Any wet-clutchapproved oil in 10w-40 or10w-50 will be aces.
STARVING SAVAGE
I have a 1995 Suzuki Savage I ® that has been given the Ryca * Motors CSi treatment. Occasionally the bike will simply sign off at 60 mph (4,000 rpm). It will run well up to that speed, but then it won’t go any faster. It does not miss. The engine runs smoothly but simply won’t continue to accelerate. It doesn’t matter if I’m going uphill or down, 60 mph is all it will do, and this threshold never varies. Other times it’s fine and will continue to accelerate normally. The problem seems to manifest itself completely at random. The engine can be either hot or cold, and the problem will spontaneously occur then clear up during my rides. I sourced a used igniter on eBay, but the problem still exists. I’d take it to a shop, but because the problem is intermittent I’ve never been able to get it to the shop when it’s acting up. The bike only has about 12,000 miles on it.
STEVE HEATWOLE CYCLEWORLD.COM
A ■ When ing, “signs an engine off” as quits you say, acceleratwith■ out any detectable misfiring, it is starving for fuel. Check to see if enough gas is getting to the carb first. Remove the fuel hose at the carb, turn the petcock to “prime,” and catch the gas into a clean cup or can. Watch the steam for a minute. It should be a steady trickle, not stop and start, at least 16 ounces in a minute. Now check the tank vent by popping off the gas cap to see if that helps. If still suspect, take the petcock apart and check for debris in the screen or valve.
If you find silty rust in the screen, you need to clean the fuel tank too. You can buy a new valve or rebuild the existing one. The valve is vacuum-operated in the “on” or “reserve” positions.
I prefer to fit a manual valve that you can turn off when you want to run the carb empty before storage. The manual valve from a Yamaha Raptor 660 will fit. Remember to plug the vacuum port going to the engine. If the fuel flow seemed okay, pull the float bowl to look
for dirt, varnish, and crud. Cleanliness is next to godliness when we are talking about carburetors.
TRIUMPHANT DEAL?
QIs * Triumph $5,500 Tiger a good 1050 deal with on a 32,000 2007 ■ miles? It has been well kept. If it is kept up with regular maintenance, how many miles can be expected from this motorcycle?
TAMMIE SOUTHER
CYCLEWORLD.COM
A ■ What you may constitutes or may not a “good” be to somedeal to ■ one else. You’ve got to decide for yourself. I think all motorcycles are a good deal, much cheaper than a visit to the shrink, and better for you.
Aprice tag of $5,500 seems about market value for a Triumph Tiger as you describe. Can’t say how long she will go for. When exactly are you planning to crash it? They’re all still going, so that’s the only way to stop ’em.
ANTI-DIVE REDUX
QThe main reason for separat* ing the anti-dive system with ■ washers/shims is not related to the braking system; it is to eliminate the anti-dive function. The anti-dive action on the left fork leg is the most common cause of the shock absorber oil retainer (fork seal) failure.
The oil retainer is not capable of withstanding the pressure produced when hitting a pothole while the anti-dive system is active. Very often in that event, the fork seal has a complete failure, and all the oil comes out immediately.
After doing three repeated regular repairs, changing the oil retainer and adding a washer to the anti-dive was the only solution that worked for me (and for
several of my friends with similar bikes) in the long term.
I did the required separation not with washers but with a nice metal piece, produced at a local machine shop.
AI understand your motivation to ■ “fix” the problem of blown fork ■ seals, but disabling the anti-dive valve is the wrong approach. Honda doesn’t design products that don’t work in the real world. The vast majority of Gold Wing owners are satisfied with the reliability and operation of their machines.
Reports of blown fork seals and rough riding complaints are largely caused by poor maintenance. Brake fluid being
hygroscopic, it absorbs moisture and should be changed no less often than every two, (2), du, dos, zwei years. If brake fluid isn’t changed on a regular basis and either of the anti-dive pistons stick, operation will be affected adversely.
Your fault is in the upper portion of the valve. This piston sticks in the “out” position, and thus the fork is always in anti-dive mode. Obviously the ride will be harsh and pressure inside the fork leg will be high when compressed. The fork seals, being the weakest link, will blow out if the anti-dive valve isn’t repaired.
Honda incorporated anti-dive into the Gold Wing fork so as to avoid bottoming out under hard braking and yet have a soft spring rate for a plush ride. If about to hit a chuckhole, it is best
ASK KEVIN
MULTIPLE THROTTLE BODIES: WHY?
QBThis is a question I’ve pondered ■many times. With many cars and motorcycles on equal footing with respect to specific output (i.e., horsepower per unit of displacement), why is it that motorcycles persist with employing an individual throttle bodyforeach cylinder whereas in automobiles a single throttle body suffices? Granted some bikes do produce higher specific output than many cars, so I assume there’s a performance advantage. Still, many bikes overlap cars with respect to horsepower per literyet still come equipped with individual throttle bodies. Seems to me that motorcycle manufacturers could take some cost out both forthemselves and, later, for customers by adopting a single throttle body, since the maintenance to synchronize them would be eliminated.
IEFF BERTRAND
A The first problem is to avoid fuel or ■ air maldistribution, either of which can cause one or more cylinders to receive an incorrect mixture. Incorrect mixture produces higher emissions and lower power than having correct mix on each cylinder.
At the races one can often see, on fourcylinder bikes, that although only one oxygen sensor is fitted in the collector pipe, there are positions (all plugged) for oxy sensors in each of the four head pipes. What this indicates is that the engine’s fuel map was “trimmed” on the dyno to establish the small corrections required to bring all
cylinders to the desired mixture strength. Once that is done, all fourfuel maps (one per cylinder) can be raised or lowered together to compensate for changes in atmospheric density or humidity. Once all cylinders are trimmed, a single oxy sensor is all that’s needed fortrackside tuning.
Something on the order of a 10 percent torque boost can be had over a modest range of rpm by choosing the correct intake length. While pipes of this correct length could all be fed from a single “log manifold,” it has always been quite difficult to get fuel added at a single point to proportion itself equally among the four cylinders at all rpm and throttle angles.
Therefore it has proven best to treat each cylinder as essentially a separate engine, with its own separate intake system and its own fuel and ignition maps, optimizing not for an average but for its specific optimum.
Another point is that motorcycles, having so little rubber on the road as compared with cars, need utmost accuracy in torque control to apply power in corners. Fourthrottle butterflies close to the cylinders do a good job in this respect.
As an example of worst-case, early development examples of the Wright 18-cylinder R-3350 engine (later powering the B-29 bomber) added fuel at a single point upstream of the supercharger, resulting in a nearly two-to-one variation in mixture strength, from the leanest to the richest cylinder. Achieving even workable improvement in this proved to be an enduring nightmare for both development engineers and flight crew (lean backfiring and induction fire on takeoff caused many
aircraft losses).
Florida some time ago revealed that its fuel-injection control models all three forms in which fuel reaches engine cylinders: (1) as evaporated fuel vapor, (2) as entrained droplets moving with airflow, and (3) as wet fuel, migrating along the walls of the intake pipe. Steady-state cruise, as in the case of a touring bike on an interstate highway, is an easy problem, but when the throttle is constantly moving, the differing time constants of the three delivery modes begin to affect mixture strength.
Bonneville is another venue in which fuel or air maldistribution in convoluted manifolds all too frequently leads to the loss of a piston. When people in the work area heara run by a strong V-8 beginning, they stop what they are doing and turn toward the “music,” willing the engine to make it through all its upshifts. One of the occasions when such a car “popped,” I heard an older man standing next to the line of waiting cars say, "There's a waste of good ice.” Fie was referring to the use of ice-andwater mixtures in the charge air coolers of supercharged cars. When you run out of ice, you have to drive into Wendoverto buy more.
If you remove the four-barrel carb from an old-time V-8 engine and look straight down into the manifold, on its flooryou will often see little guide channels. These were intended to guide wet fuel to weaker cylinders. In the case of “log” manifolds, points of junction were often sharp rather than smoothly radiused, the aim being to allow wall flow fuel to strip off at the sharp edges, rejoining the airflow.
-KEVIN CAMERON
practice to try to avoid the hole! Look where you want to go, not where you are. If possible, brake as hard as possible before the hole and let off an instant before the front wheel hits the hole.
The anti-dive will then be released and it will be easier on your backside, front tire, and rim as well as your fork seals.
SLOBBER
QI would greatly appreciate it if ® you could shed some light on the ■ frustrating problem of “oil carryover,” a fairly common condition with Harley-Davidsons.
I own a 2009 FLTRSE3, which I purchased new and have maintained meticulously. The lioci engine has slobbered oil since its first oil change at 1,000 miles. The condition has probably gotten a little worse over time. Oil seeps out of the air cleaner just as described in an H-D Service Bulletin.
I did the procedure described in the bulletin and kept the oil level a halfquart low.
I installed a K&N filter so that I can
wash it about every 500 miles. The slobbering is generally associated with riding at highway speeds during which the oil blows out of the CVO open element air cleaner assembly onto my right leg and side of the motorcycle.
The service department at the dealership where I purchased the bike dismissed the issue as being caused by an overfilled engine oil level—even after they did the oil change. I recently took it to another dealership where I got to speak to the technician who checked it. He confirmed the problem but stated that it is “within tolerances.” (It certainly did not seem rational to insist that the technician tear into the motor just to be sure.)
It seems that I must either live with it or sell the bike. Any expert advice?
WILLIAM F. MURRAH III, MD FAIRHOPE, AL
A Obviously your first bike wasn’t a ■ Triumph Tiger Cub.
■ Oil out the breather at high speeds is a common issue on Harleys. You did the right thing when you chose
not to tear down the engine. There’s a more than good chance you wouldn’t see anything amiss and put it back together only to find the problem still there. Diagnose first. In case you were distracted, diagnose first! I can’t stress this enough.
First, get a leak-down test performed to see if there is too much pressure in the crankcase from ring blowby. Next, check for crankshaft “scissoring.” Scissoring is the flywheels shifting relative to each other on the crank. Harley had a problem with this on some bikes in ’08 and ’09. You’ll have to take the cam box apart to put a dial indicator on the exposed end of the crank. If it wobbles, it hogs out the gearotor pump and it doesn’t scavenge properly. The fix is a new crank, oil pump, etc. (expensive!).
If both those items check out okay, you may get some improvement by fitting a larger oil pump, for better scavenging. Harley also has a new type of breather element that will reduce the amount of oil making it to the air cleaner.
VANISHING VOLTS
Two days after a ride, I plug my ' BMW KiooLT into a battery 1 maintainer. The maintainer will keep the battery at 13.27 volts DC. Upon disconnecting the maintainer, I monitor the battery’s state of charge and the multimeter shows a constant trickle “discharge” from the 13.27 volts until it reaches 12.47 volts. Then the battery will stay at 12.47 VDC for several days. Since the only item drawing juice from the battery is the dash-mounted clock, I am puzzled as to where this electrical charge is going. And why does it trickle off upon disconnecting the battery maintainer right before my eyes?
Alt is absolutely normal for a bat■ tery to return to its standing ■ voltage once it is no longer being charged. Charging voltages are always going to be higher than the reference battery voltage. It doesn’t matter how it was being charged, whether by a maintainer, charger, generator, or alternator. Now, if your battery voltage continued to decline beyond 12.47 fairly rapidly, then I would say you have an excessive drain.
The clock isn’t the only component that sucks milliamps when the ignition is turned “off.” Other circuits also do to a smaller degree. Remember nothing is absolute—diodes leak, and even insulated wires running parallel to each other will leak a tiny current. I once had a Jaguar in my shop that would crank the starter motor when the windshield wipers were turned on! That was damp battery acid carrying enough current to short terminals in a harness connector.
Your battery voltage is on the low side of the normal range. A good, fully charged, lead-acid battery will typically have a standing voltage of 12.7 to 12.9 volts. The exact voltage is dependent on ambient temperature (higher equals higher), the state of charge (if you have just taken it off a maintainer, it is not an issue), the specific gravity of the electrolyte from new (more concentrated equals higher standing voltage), and how sulfated (old) the battery is. CUM
A GOT A MECHANICAL OR TECHNICAL Nr PROBLEM WITH YOUR BELOVED RIDE? Perhaps we can help. Contact us at cwservice@ cycleworld.com with your questions. We cannot guarantee a reply to every inquiry.
