Service
SERVICE
We welcome J~'our technical questions and comments, and will publish those we think are oJ interest to our readers. Because of the volume of mail received, we cannot return am personal replies. Plea.ce limit your "Service" letters to technical subjects only, and keep theni as brief as possible. Send then, to: `Service, "CYCLE WORLD. /499 Monrovia .4ve...\ewport Beach, Calif 92663.
FULL TANK VS. EMPTY
I recently purchased a 1981 Honda CM400A. Due to Chicago weather, I stored the bike for the winter months. My question to you is, after receiving a variety of answers from friends and dealers, is it safer to drain the gasoline from the tank and lines or fill the tank completely with gasoline and add Sta-bil or some similar product?
Frank A. Pasquale
Bellwood, 111.
Your best bet is to leave the tank filled right up to the top, and if you won’t be riding it for many months add a can of gasoline stabilizer, such as Sta-bil. Leaving the tank empty can allow water to condense inside the tank, causing rust, and it can also dry out seals and gaskets on some bikes, making them prone to leakage. Ideally, it’s better for the fuel system and the bike as a whole if you can find a long enough break in the winter weather (one of those odd-ball February thaws) to get the bike out on the road and run a tank of gas
through it. This is not always possible, of course, if the weather doesn’t cooperate or if the bike has been winterized and locked away in storage.
CREATIVE WIRING
I have a service tip which might be of use to you. Recently the voltage rectifier on my aging Suzuki GT550L suffered an internal breakdown which disabled the charging system. Rather than plunk down $45 for a new one, I determined to take matters into my own hands. I sat down with the rectifier and an ohmmeter and discovered that only one of the nine terminals on it was shorted to ground. The rest seemed to function normally.
I found that Radio Shack sells a full wave bridge rectifier, part number 267-1 185, rated at 25 amps and 50 peak volts, which is fine for most motorcycle alternators. I clipped the wire from the shorted terminal on the old rectifier and soldered a lead onto it, one to the output (red) wire and one to ground. Back at the ohmmeter again, I connected the leads to the new rectifier so the current flow was as specified in the manual. Luckily the new rectifier has a mounting hole in the center and drilling it out a bit was all that was>
needed to mount it directly to the old rectifier, neat as a factory setup. The whole job took about an hour and cost $2.69, plus tax.
Seems to work great so far. The old Suzuki is back on the road and the battery charger is back on -the shelf where it belongs.
Bill Peterson Kennewick, Wash.
LEAKING J. MODEL
My friend and I both purchased new 1981 Kawasaki KZ1000 J models. Both our bikes have one common problem, each bike leaks oil out of the cam plug fittings on both sides of the engine. We both work for a police department, and have noticed the same leakage on the police cycles, alsdl Kawasaki 1000s. Is this problem inherent on the 1000s, and if so, what can be done for it.
Bill Lees
Lawrence Police Dept.
Lawrence, Mass.
Oil leakage from the cam plugs ha$ been a problem on the KZ1000J, but there is a fix for it. Get a new set of end plugs and wrap each one tightly with eight layers of Teflon tape—the kind normally used on plumbing joints and high pressure fittings—and install the new plugs. Our local dealer reports this solves the problem permanently.
ELECTRIFYING THE HAWK
I own a 1979 Honda Hawk Type I. This bike does not come from the factory equipped with an electric starter. Would it be possible to install an electric starter on my bike?
Brice Guile Griswold, Conn.
Installing an electric starter on the Type I is probably possible, but the cost of the labor and parts involved in doing so would be prohibitive. Honda shows a different part number for the electric start crank because the starter clutch is located on the crankshaft on the Type II and the journal for the clutch bearings is built up to a larger diameter than that on the Type I. The lower engine case would also have to be replaced to provide the starter mounts. That, with the cost of the starter itself and the difficulty of revamping the wiring har* ness to include the starter relay switch, change relay, fuse, starter button and heavier battery cables, would bring the cost of the project very close to the price of a good used Hawk with an electric starter.
REED WEAR
I have just installed a set of Boyesen Power Reeds in my 1980 IT125G and am>
enjoying the gain in power. How long should I expect these reeds to last? Or, more to the point, how long before I should start inspecting them? Also, what kind of power gain can I expect from putting on an aftermarket silencer and spark arrester. I’ve heard several different claims, but thought I would check with you.
Bruce G. Gillies Meridian, Miss.
The Boye sen reeds are relatively durable and should last for a season or more of riding, depending on how often you go. When the reeds start to wear they will develop a feathered or tattered look on the tips of the synthetic reed material. You’ll know if they get really worn because the bike will be hard to start and will lose power and generally run poorly.
Aftermarket spark arresters are a good way to make bikes that didn’t come with them forest legal and they are normally a few pounds lighter than stock spark arresters, but most of them we’ve tried provide either no power increase or a small loss in power over the stock factory arresters.
SORTING OUT THE KZ
In reference to your January, 1981 issue in the service section, Jets, Pipes and Filters, I too experienced the very same jetting problems Mr. Debbs related, using stock carbs and later 29mm Smoothbores with K&N filter pods. I simply couldn’t get the jetting right no matter what combination of needle settings and main jets I used. My bike is a 1977 KZ1000, stock except for Smoothbore carbs and a Kerker exhaust.
Throwing away the K&N filters, putting the airbox back on without the screens and silencer, # 120 main jets, #25 pilot jets, a large clamp-on type K&N filter that fits on the intake hole of the airbox, all produced a smooth running and super accelerating motorcycle. The Smoothbores truly give the KZ1000 a shot in the arm.
L. Graves Beloit, Wis.
STARTING THE RT
I recently purchased a 1972 RT360 Yamaha and have had some starting troubles
since. A small dose of fuel through the spark plug hole and she fires up every time and continues running if rpms are kept up for the first 10 sec. or so. I have soaked and cleaned the carburetor and am sure that all the passages are open. The reeds are clean and in good condition. The engine runs great at all throttle settings, and starts when warm with no priming at all— one kick. What could be causing this problem? I’ve checked and doublechecked the carb and am baffled.
Jerry Giles
Newton, Kans.
It sounds as though you have everything in good working order except the choke, which on the RTis a slide-type enrichening device. Remove the enrichening tube from the top of the carb and make sure the holes in it are clean, then blow air through the passageway below the tube into the carb throat to check that it’s clear and fuel is getting through.
DOUBLE DISC GS
I’ve got a ‘79 GS1000N that I specifically bought over the EN to get the wire wheels. I prefer the look of spokes, as well as the weight savings over factory cast wheels. Since then I’ve taken the bike down the cafe route, and am presently stumped on improving braking. How can I put a second disc on the front without buying a whole new front end? Some say I can flip a stock slider/caliper setup around and run it on the other fork leg. I’ve actually seen this done on an AFM 1000 with spoke wheels. Others say this is not the solution. Generally, no one knows for sure, so I really need a definitive answer. I would like to keep the larger disc size provided on the ‘79 1000N vs. the smaller dual size discs. Assuming I’m going to used braided lines and have the discs drilled, how do I go about getting reliable, two-finger stoppers?
Steve Roach
Pensacola, Fla.
Dual disc conversions work very well on the GS WOON because, as you mention, the disc size is larger than that on the double disc E models. The second disc can be mounted by using another stock left hand slider and caliper assembly and flipping it around for a right hand installation. The wheel hub is already drilled for a second disc, so all you need to mount is the disc itself and the appropriate bolts. You will need a master cylinder from a dual disc E model to get proper hydraulic advantage, as the later master displaces more fluid and has a larger piston. A T-fitting is also required, of course, for the dual brake lines, and the E model junction will work fine. S
