Bogging on Full Throttle *SOLVED

[scootertrashrk]

Greetings,

I am currently working on a 2007 Schwinn Collegiate. Started as a broken belt. Been sitting for a few months. It starts and idles great, take off is ok too. But when I hit full throttle it bogs. Power is there and then it's not.

I recently:

Adjusted the valves
Cleaned the carb
Cleaned the pick up coil
Drained and replaced old gas
Replaced the belt and slider weights
Threw on a different CDI , no difference




This is not the EXACT canister, the one I am looking at has only two half inch hoses running from it, one connected to nothing.

I have not seen this type of canister before. Plugging that hose or leaving it open does not change the bogging situation.

The intake manifold vacuum line is connected to a Y spliter > One to fuel valve and one to a 3-Way valve. The Thr3-way valve then connects to the head emissions and the canister. Yet the canister is connected to nothing.

Im leaning towards checking the compression, spark plug cable resistance and the pick up coil wire.

Any help or ideas? Thanks Yall!

[stepthrutuner]

Sometimes main jets look clean but still have a film of deposits in the passage impeding fuel flow. Try cleaning with some sort of close-fitting wire, straight pin, needle or taughtly stretched thread or unwaxed dental floss with the jet threaded on the string (roll the jet back and forth on a board while stretching the thread with your hands after spraying with carb or brake cleaner).

[Goosey]

The emmisions control thing, that canister, usually go to a tube comeing off the end of the engine by the valve cover, the airbox, and the manifold. If you don't have inspections you can remove the whole set up, plug off all those connections. The air box connection is shown here on mine ( 150cc )

[prodigit]

could it be that you improved airflow/exhaust, and forgot to upjet the carb (meaning engine is running lean)?

[scootertrashrk]

Solved!::: :scoot2:

It was either a dirty connection on the coil pick up wire to the CDI or it was the ground wire that connects from the valve cover bolts to the frame. Cleaned both of the connections and it purrs now. I was getting intermittent spark, explaining the on and off again power.

After it was running right, I changed the 72 main jet to a 78. (85 was too big). Definitely a noticeable difference but not by much.

To finish this tune up I will probably replace the spark plug and rear gear oil.

Thanks for the replies guys!

[stepthrutuner]

The old weak spark ailment. Glad you found it.