QuestionQUESTION: Hi Wayne,
Where to start...Got a call from a friend..bike was broke down in a no start condition. Went out and found it was flooded. Dried plugs and flooded immediately. Towed bike to my house.
Changed plugs and still no start with flooding. Thought float(s) might be stuck. Pulled carb off bike and cleaned float bowl out but didn't remove float needles or jets. Reinstalled with same problem..flooding.
Removed again and pulled out jets in float blow and float needles and seats. Sprayed combustion chamber cleaner through carb passages and blew out with compressed air. Cleaned float seats and jets with same cleaner and reassembled.
Bike fired up perfectly with no choke needed. Idled fine. Went to ride it but it stalled immediately on take off. No acceleration past part throttle. The bike almost seems fuel starved but I'm not sure.
Took floats out again and readjusted to provide more fuel. Starts a little harder now but still starts. Just can't seem to get it to accelerate part part throttle.
Am at wits end now and at a total loss. Thinking I did something to the throttle position sensor but can't see that happening and am not sure if it would cause my present issue.
The only jets I removed were the ones in the float bowl. Nothing else was disassembled.
Any help is appreciated. Thank you in advance.
Sincerely,
Rick
just thought of this...could I have ripped one of the diaphrams while using the compressed air? I did not remove the vacuum chamber cover.
ANSWER: Hi Rick,
Looks like Pandora's box has been opened, :)
You may be correct about some diaphragms but
they might be the coast enrichener diphragms on
the side of the carb under a small plate with two screws.
Also, the float needle seats on these bikes have small
o-rings which can go bad and cause a flooding problem
even if the needles and float level are correct.
The float or fuel level should be set so the bowl is full and even
a few milimeters above the float chamber line.
Check the slide diaphragms and coast enrichener diaphragms
and replace the float seat 0-rings. Set fuel float heights
and try again! I know it is a pain in the ###@@@@&&&
but check everything very carefully and hopefully
it will work.
WS
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QUESTION: Thank you Wayne for the advice,
I will try your suggestions but am wondering about the throttle.
The bike revs up normally until just past 1/3 throttle. Quick, low revs are fine but slowly opening throttle stalls out. Does this sound like a starvation issue related to float level? Could it be TPS related?
Thanks again,
Rick
AnswerRick,
The float level can be a very sensitive adjustment and has to be very close
to the recommended fuel height or the engine will be starved for fuel.
Since your original problem was flooding I don't suspect the TPS.
TPS can cause surging, bucking and stalling mostly.
The throttle opening you mentioned is most affected by fuel height
and the slide needle position in the main jet/emulsion tube.
Under the main jet is the jet holder which has a tube which goes up the
center of the carbs. This emulsion tube has many small holes to dispurse
the fuel and can often get plugged up.
This is the tube where the slide needle enters the carb.
A lack of fuel in the float bowl can also affect this area.
The VStars run very lean and so anything that prevents fuel
flow will affect it adversely. Even trying to run without the air cleaner
can often make them hesitate.
Also any loose or open vacuum/air hoses can cause problems.
I would set the float levels spot on and just make sure
carbs are clean and assembled correctly with good o-rings on float needle seats.
Assemble it all and make sure carbs are synchronized
or opening at the same time.
I believe these carbs also had carb heaters which must be plugged in.
Battery must be full and tightly connected.
Here is a link to throttle opening relative to carb operations:
http://www.totseans.com/cms/sites/default/files/2stroke2.jpg
http://justkdx.dirtrider.net/images/graph.jpg
As you can see 1/3 throttle and up is handled most by the carb needle position in the emulsion tube
and the fuel level in the bowls.
Good luck!
WS
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