Keihin CV-40 Carb

Gas spray

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56pan
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Re: Keihin CV-40 Carb

#16

Post by 56pan »

That's what I've been told. So, I installed a little bigger pilot jet (45 to 48). I can turn the adjustment screw almost all the way out and still popping. My main jet is 180. Do you think it I need to install a 50 pilot jet? Rained all day so no test ride. I let the bike warm up in my shop. I have 2 fans blowing on the engine to keep it cool. Thanks
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Re: Keihin CV-40 Carb

#17

Post by Panacea »

I ran a 50 pilot on my 51pan, but it's also a stroker, What is your starting routine?
56pan
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Re: Keihin CV-40 Carb

#18

Post by 56pan »

Usually 1/2 choke, retard distributor a little, 2 kicks closed throttle, 2 kicks wot, turn on ignition and kick till it starts. I am going to install a 50 jet next. Thanks
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Re: Keihin CV-40 Carb

#19

Post by RooDog »

The CV carb does not have a "choke" per se, but rather a separate starting circuit activate by the pull up "choke" knob. Yes it is adjustable, but should be fully engaged for cold starting, and then modulated for engine speed during warm-up. The accelerator pump should negate the need for key off priming kicks. A slightly open throttle also impedes the function of the "choke", actually an enriching circuit. Ideally one or two squirts of accelerator pump, closed throttle, choke fully engaged, key on, and start kicking, should light the fire. But then, every machine has its own combination.
My Panny with a Bendix required only a squirt or two, a little throttle, no choke, and one or two key on kicks to get started, even in cold weather.
Priming kick often tend to over gas, flood, an engine, requiring more kicks to dry it out.
Just some things I have noticed over the years.....
....RooDog....
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Re: Keihin CV-40 Carb

#20

Post by Panacea »

Try no enricher , just twist the throttle a couple times and kick it over, with just enough retard so it doesn't kick back.
56pan
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Re: Keihin CV-40 Carb

#21

Post by 56pan »

I will give that a try. Thanks
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