The Service Department
THE SERVICE DEPARTMENT
GARY BRAY
WHOSE OIL SHOULD I USE?
I have a 1957 Harley-Davidson 165 and I would like to know what other kind of oil will mix with the Gas. besides H-D two-cycle oil. I have heard that airplane oil will mix. Is this true? Your help will he appreciated.
William Farmer Rocky Mt.. No, Carolina
Most types of oil can he mixed with gas for use in two-cycle engines. I would recommend using oil designed especially for the two-cycle, however. Two-cycle oil burns cleaner and does not leave a carbon deposit on cylinder walls, bearings, etc.
The use of the proper oil in a two-cycle should give longer engine life and better performance.
JET TROUBLE
/ recently had a 550 kit installed in my Honda Super Hawk. As you reported, the performance increase is very evident and the conversion is well worth the tune and money involved.
My problem is in findinp the proper jet size for the carburetors. In the December 1965 even wo RID you reported that after all the fiddlinp around with jets. YOU found yourselves riplit back with the stock jets. However, my spark pi ups run hot and indicate too lean a fuel mixture.
Rob Rxder
San Francisco. Calif.
In a situation such as this there is no specific jet size to use. Different atmospheric conditions require different jetting, let sizes may also vary from machine to machine and. in the case of multi-cylindercd engines, there may be a slight jet size difference from cylinder to cylinder. Jet your carburetors according to your plug readings.
STREET VS. DRAG
How hard is it on a hike to drap race? / don't meati one just for the strip, but a street bike used few everyday transportation. Also, if you drap race does the bike need any type of special equipment?
F. M. Schrey Chicapo. Illinois
It very definitely is hard on any street bike to drag race, as they weren't manufactured for that purpose. As to how hard, this would depend on how often the machine is used for this endeavor. In any form of high speed racing there is no guarantee that one will not suffer some form of mechanical trouble. A missed shift here and there, the wrong jet or too hot a spark plug, and your machine suffers. If the hike is used for transportation, hut the rider feels he must compete, then he must decide how deeply involved he wan's to become in racing.
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An occasional blast down the drag strip certainly shortens engine and running gear life, but if it becomes a once a week event, then the owner will find that his transportation has become less dependable and is costing him more to operate.
Concerning special equipment, the rider should have boots, a set of leathers, gloves, goggles, and an approved helmet before he ventures onto the drag strip. The machine should be prepared in a safe manner, with attention given to tires and keeping the machine clean, w'ith all nuts and bolts tight. The competitor will find that he needs a variation in jet sizes and colder spark plugs for racing, along with possibly one or two gear changes for the rear wheel.
These are the basic necessities needed to get on the drag strip. From here on the modifications become more costly and time consuming.
HELP!
I have a I960 model Sliowa motorcycle. A/v piston went had and I can't locate’ one. This motorcycle came from Japan hut / have tried without success to locate a Sliowa dealer. A Honda piston will not fit. Can you offer any help'.’
Roper Cumminps,
Dunhar. West Virginia
We have no information regarding Show'a importers or dealers in this country.
( If anv of our readers can help, contact Mr. Cummings at 144 Oak St., Dunbar, W. Va.)
You may find you will have to acquire the necessary parts for this machine by writing to the factory in Japan. If you do not have this information. I am sure the Japanese C ouncil in Washington. D.C. can supply you with the necessary address.
YDS-2 CLUTCH DRAG
/ have a /964 Yantaba YDS-2. At the first oil change I overfilled the case a little and the dutch would not release all the way. We drained off the excess oil hut this made no difference. The plates were then replaced hut no matter how ur adjusted it. it still will not release. The dutch cable has also heen replaced.
Dean Lowrunce Cut Rank. Montana
If your YDS-2 had been performing satisfactorily up until the oil change, then I suspect you may be using too heavy an oil in the clutch case. I would try using SAF 20. If this has already been tried (or is tried and does not cure the problem), I suggest you replace the following spacers and reduction gear sleeve: Thrust washer outer #430407; thrust washer inner #430406: thrust washer inner
#430408: thrust washer inner #430410, and reduction gear sleeve #430404.
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SOFT SUSPENSION
/ would like to know wliat can be done to eliminate the soft suspension of the Yamaha YDS-2? This is most noticeable at high speed.
Ira D. Sie asman Bellingham. Washington
The front forks can be stiffened by installation of a spacer between the bottom triple clamp and fork spring. There is a rubber bumper in the Yamaha fork. If \ CHI w i 11 acquire one of these rubber bumpers and cut it in half, using it between the spring and fork stem of each fork leg. this should sufficiently stiffen the front end.
The rear shocks can be stiffened in the same manner, but here a small spacer will base to be made. The Girling shock absorber that is standard equipment on most English machines will also fit the YDS-2 Yamaha by merely replacing the Girling mounting rubbers with the YDS-2 mounting rubbers.
WHAT GEAR?
/ am a new rider and have a problem concerning riding technique. I have three main troubles that bother me most. When riding in heavy traffic, at what speed should I travel and what gears should l use? What speed should I use when I make a turn'? When I come to a stop on a hill at a red light, how do 1 keep my machine stopped and how can / get underway without stalling when the light has changed to green'? It always seems hard to start once it stalls.
Jim Kalmbach Philadelphia. Pa.
The best way to tell if you are in the proper gear is by the sound of the engine. A motorcycle engine should always be allowed to run free, or should I say, “sound happy.” When riding up a hill or in the mountains, one must select a gear that allows the engine to pull without lugging. This will come with experience.
The difficulty encountered in starting your machine once it has stalled is, I am sure, a lack of experience and familiarity with your machine, and will all come in time. Everyone who has a motorcycle has gone through the same difficulties at one time or another. When driving in heavy traffic it is best to move at about the same speed as the rest of the traffic and use a gear low enough to give you good acceleration. Remember to stay alert. About selecting a gear for cornering I can only say that this requires experience, for some corners are 1st gear, some 2nd, and so on.
Stopping at a red light on a hill is a very common problem and some rather tricky control manipulation is needed to get started again. As you come to a stop, apply the front brake while shifting into neutral. When the light changes to yellow for traffic approaching from either side, shift into low gear and then apply the rear brake to hold you. As the light changes to green, apply power and slip the clutch while gently releasing the rear brake.
