Which cylinder?


Information and questions on GL1200 Goldwings (1984-1987)
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Rusty Bike
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Motorcycle: 86 GL1200 SEi, 98 Valkyrie Std, 78 Yamaha XS750SE, 86 Honda XL125, 4.5 HP belt drive Minibike my dad built, foot clutch!

Which cylinder?

Post by Rusty Bike »



Hi folks. My SEi has a low speed miss at times. As the RPM's come up I can feel a boost as if a cylinder started making power. This does not happen all the time. At cruising speed all seems well. The weather is still decent so I would like to identify the errant cylinder while I can still ride. So, how do I do this? How do I figure out which cylinder is loafing at low RPM. After the snow flies, I can tear into the problem but now is the time to ID the problem I feel. Thanks...Rusty



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twocams
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Re: Which cylinder?

Post by twocams »

Could pull the 4 spark plugs, see if any look different. Might hook up a timing light to each plug wire while the bike is running. See if there is a misfire or anything. If you can hook up a vacuum gauge watch the gauges see if one has a hiccup?

twocams

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roadwanderer2
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Re: Which cylinder?

Post by roadwanderer2 »

im not sure if the same would apply, but what i used to do with a motor that had a misfire, i would take out each plug one at a time, leave it connected to the plug wire, fire the motor up and see how good the spark was going across the electrode, or, while the motor is running, try to remove the plug wire without getting yourself shocked and see if it changes the idle. if the motor doesn't drop in idle speed, chances are you have a faulty spark plug or plug wire. always go for the simpler things first.

stuart.

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