Exhaust valve question

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Kwee
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Re: Exhaust valve question

Post by Kwee » Tue Aug 28, 2018 6:32 pm


At steady speed(closed loop), the bike is gonna understand(via O2 sensor) that the bike run leaner(than with the valve in place) and enrich the mixture. That also reduce low end torque. So fuel economy is gonna be compromised.
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vcyclenut
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Re: Exhaust valve question

Post by vcyclenut » Tue Aug 28, 2018 7:43 pm


Kwee wrote:
Tue Aug 28, 2018 6:32 pm
At steady speed(closed loop), the bike is gonna understand(via O2 sensor) that the bike run leaner(than with the valve in place) and enrich the mixture. That also reduce low end torque. So fuel economy is gonna be compromised.

My o2 sensor is disabled so that's not what caused the slight loss in power
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Re: Exhaust valve question

Post by Kwee » Tue Aug 28, 2018 10:50 pm


vcyclenut wrote:
Tue Aug 28, 2018 7:43 pm
Kwee wrote:
Tue Aug 28, 2018 6:32 pm
At steady speed(closed loop), the bike is gonna understand(via O2 sensor) that the bike run leaner(than with the valve in place) and enrich the mixture. That also reduce low end torque. So fuel economy is gonna be compromised.

My o2 sensor is disabled so that's not what caused the slight loss in power
So that's why you don't feel too much lost of low end torque. On many bikes, disabling the o2 sensor cause the bike to run a bit rich for safety reasons.

And with much air and much fuel you can fight low end torque lost at the price of a slightly higher fuel cunsumption.
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Re: Exhaust valve question

Post by vcyclenut » Wed Aug 29, 2018 11:29 am


Kwee wrote:
Tue Aug 28, 2018 10:50 pm
vcyclenut wrote:
Tue Aug 28, 2018 7:43 pm
Kwee wrote:
Tue Aug 28, 2018 6:32 pm
At steady speed(closed loop), the bike is gonna understand(via O2 sensor) that the bike run leaner(than with the valve in place) and enrich the mixture. That also reduce low end torque. So fuel economy is gonna be compromised.

My o2 sensor is disabled so that's not what caused the slight loss in power
So that's why you don't feel too much lost of low end torque. On many bikes, disabling the o2 sensor cause the bike to run a bit rich for safety reasons.

And with much air and much fuel you can fight low end torque lost at the price of a slightly higher fuel cunsumption.
I don't agree with your initial assumption it is lean in that area with the exhaust valve left open

the valves are used to keep exhaust velocity up to increase scavenging effect. The bike is actually rich in that area of power loss when the valve is left open.

I have the data logs to show it
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Kwee
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Re: Exhaust valve question

Post by Kwee » Wed Aug 29, 2018 2:34 pm


Another question vcyclenut, the Eco light is related to the o2 sensor or it's a different animal ?
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Re: Exhaust valve question

Post by vcyclenut » Wed Aug 29, 2018 3:20 pm


Kwee wrote:
Wed Aug 29, 2018 2:34 pm
Another question vcyclenut, the Eco light is related to the o2 sensor or it's a different animal ?
Im not sure, I don't test it , really no benefit to me to know what makes the light come on.
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