Air Cut Off Valve

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05-19-2008 | 01:36 PM

1baddoggie

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Squid

Joined: Mar 2008

Posts: 8

Air Cut Off Valve

I have been troubleshooting my deceleration popping and was wondering if anyone has every tested the air cut off valve? Engine braking (the manual calls it) popping out the exhaust is cause by a too lean condition and the air cut off valve is suppose to cut the air supply to the pilot system at some given level of vacuum thereby richening it for that condition. The manual does not state what vacuum point it should close/open.
The bike configuration;
2 Bros slip on
PAIR valves have been blanked off
All emission removed (CA)
It has stock jetting
I have checked for air leaks and that seems good
I pulled the carbs a second time to check everything over and looked at the air cut off valves, that is when I came to the issue of being able to check them accurately.

Thanks

05-19-2008 | 02:21 PM

RCVTR

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From: South Lake Tahoe, CA, USA

RCVTR is an unknown quantity at this point

My 49 state bike didn't have air cutoff valves. when I put 2 bros slip-ons on it I started to have lean decel popping. A #45 pilot jet was the cure.

05-19-2008 | 02:51 PM

drew_c14

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Posts: 2,455

From: Williamsburg, VA

This might be a stupid question, but...

When you removed the pair you did block off the vacuum ports right?

05-19-2008 | 04:53 PM

Hawkrider

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Hawkrider will become famous soon enough

There is a procedure in the manual for checking them, though it doesn't give a specific vacuum spec for it.

05-19-2008 | 06:03 PM

1baddoggie

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Squid

Joined: Mar 2008

Posts: 8

Quote:

Originally Posted by drew_c14

This might be a stupid question, but...

When you removed the pair you did block off the vacuum ports right?

Yes, and the one for the Evap system.

05-19-2008 | 06:07 PM

1baddoggie

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Squid

Joined: Mar 2008

Posts: 8

Quote:

Originally Posted by Hawkrider

There is a procedure in the manual for checking them, though it doesn't give a specific vacuum spec for it.

Yes, kinda odd since they do give it for testing the PAIR valve. You would want it to engage and dis-engage at the right vacuum points...you'd think...

1bd