Motorcycle Repair: Yamaha v-star classic wont run off choke, jets air, yamaha 1100

Question
I have a 2000 YAMAHA 1100 v-star classic. I have Cobra slash cut pipes, Hyper charger and a jet kit all installed by the dealer when new. Only on d-cell it has a small amount of back fire and coughs. At a steady 25 miles an hour the same thing, bucks and coughs. At one time the dealer had checked the carbs and found the pilot jet was clogged then it ran like a clock but one year later the same thing back to the dealer but the mechanic wouldn't check the pilot jet and said it was bad gas but still coughs and small backfire on d-cell. The bike has sat for a year now and the only way to start it is full choke and runs at fast idol but if you try to take the choke off it will bog down and stall. The throttle is also obsolete. If you try to turn the throttle the machine will stall. Even if the choke is on half way the bike wants to bog down and stall. But even half way on the choke if you even try to begin to turn the throttle slightly the machine will stall. Cant touch the throttle at any time. The machine will only run with full choke. Thank You Scott

Answer
Hi Scott,

If the bike sat for a year without running the carbs
are sure to be pretty gummed up and jets
or carb circuits may also be plugged.

Here is a possible solution if you are not
able to have the carbs soaked and cleaned
fully.

Go and buy some Yamaha carb cleaner only
as it is safe for carb parts.

Drain the old fuel from the carbs.
Fill the carbs with the carb cleaner
and leave them soak for an afternoon.

Drain the carbs and let them fill with fresh fuel again.
You may have to drain the tank too if the gas is stale.

Try starting it again and if it still won't run
you can either try filling the carbs again
with carb cleaner or remove the carbs and
do a thorough carb soak and clean.

If you are lucky the carb cleaner might loosen
up the goo and then a long drive might clean
it out. If not it sounds like the backfires are
from a lean fuel mixture or plugged jets.

Air leaks around the intake rubber can also
cause lean fuel mixtures but sitting
so long points more toward plugged carbs.

When you open the throttle you are increasing the
air flow and if the carbs can't provide the fuel
it will die.

Wayne S
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