Jump to content

Voltage across Flapper valve wiring?


Urbanengineer

Recommended Posts

Hi guys, just ironing out the final issues with my VFR and I wanted to see what voltage I should be getting to the Flapper valve plug.

 

I pulled the neutral sensor and turned on the bike (this should activate the flapper) and the flapper did not “pull up” so now begins troubleshooting.  

 

Resistance is good across the flapper control unit prongs, but im getting no voltage or resistance on the wires coming in from the throttle body loom. Wanted to see what your thoughts were, and if someone could please check over 10 minutes on their bike it would be much appreciated. Two prong connector attached to the flapper unit. 

 

I want mine to run like OEM...

85AA8860-01E8-400C-AB6B-BA56D5E6C398.jpeg

8BC5938B-ABAF-48B5-9E47-80D1D47C634F.jpeg

Link to comment
Share on other sites

That’s why you remove the neutral sensor wire - it should activate the flapper. I’ll tear into the Fsm during down time at work tomorrow. Thanks for your reply. 

 

(It’s supposed to be vacuum driven when in gear below 5500 RPM) (plop).

Link to comment
Share on other sites

  • Member Contributer

Hi Urban.

After checking the wiring diagram. The ECM provides a switching Ground for the Variable Intake Solenoid. So this means on the two wire cable feeding the valve one of the wires will have permanent 12v to it. So with Ignition to ON, have your Black voltmeter lead to frame/ground or the negative terminal of your battery, then probe the two wires of the plug (DC Volt Range on the meter). One of the leads will indicate 12v this should be the BI/W wire. So first establish you have this 12v.

 

I remember doing the same functional test as mentioned in the Service Manual and like you had no luck with it. This is why I suggested simply hooking up a test lamp to the plug, go riding under varying conditions and whenever the light illuminates would be when the Flapper is told to Close, you would soon get a feel for what the hell the true conditions for it to operate are. The Service Manual is vague and there are many wide and varied thoughts as to exactly when this thing should operate.

Cheers.

P.S. Strange your meter is only showing HV in the top left corner, you'd normally see zeros or something else on the display as well !

Link to comment
Share on other sites

9 hours ago, Urbanengineer said:

That’s why you remove the neutral sensor wire - it should activate the flapper. I’ll tear into the Fsm during down time at work tomorrow. Thanks for your reply. 

 

(It’s supposed to be vacuum driven when in gear below 5500 RPM) (plop).

 

I think there's an important operating principle that Urbanengineer is pointing out here:  The fact that the Flapper is electrically controlled but vacuum operated.  So when it is electronically "activated" it still needs intake vacuum (from a port on the solenoid valve that connects into the airbox).

 

Which is to say there's a difference between "enabled" vs. "activated".

Link to comment
Share on other sites

9 hours ago, Grum said:

Hi Urban.

After checking the wiring diagram. The ECM provides a switching Ground for the Variable Intake Solenoid. So this means on the two wire cable feeding the valve one of the wires will have permanent 12v to it. So with Ignition to ON, have your Black voltmeter lead to frame/ground or the negative terminal of your battery, then probe the two wires of the plug (DC Volt Range on the meter). One of the leads will indicate 12v this should be the BI/W wire. So first establish you have this 12v.

 

I remember doing the same functional test as mentioned in the Service Manual and like you had no luck with it. This is why I suggested simply hooking up a test lamp to the plug, go riding under varying conditions and whenever the light illuminates would be when the Flapper is told to Close, you would soon get a feel for what the hell the true conditions for it to operate are. The Service Manual is vague and there are many wide and varied thoughts as to exactly when this thing should operate.

Cheers.

P.S. Strange your meter is only showing HV in the top left corner, you'd normally see zeros or something else on the display as well !

Good idea. I was testing the wrong bits. I’ll try this out later this week and get back to you. Appreciate the thorough reply. 

Link to comment
Share on other sites

2 hours ago, GreginDenver said:

 

I think there's an important operating principle that Urbanengineer is pointing out here:  The fact that the Flapper is electrically controlled but vacuum operated.  So when it is electronically "activated" it still needs intake vacuum (from a port on the solenoid valve that connects into the airbox).

 

Which is to say there's a difference between "enabled" vs. "activated".

I’ve confirmed it has good vacuum to the electrical switch, but the electronic signal to “close/open the vacuum valve” never seems to get to the flapper vacuum unit and cause it to allow vacuum therefore closing the flapper plastic at lower RPM. 

Link to comment
Share on other sites

  • Member Contributer
17 hours ago, Urbanengineer said:

That’s why you remove the neutral sensor wire - it should activate the flapper. I’ll tear into the Fsm during down time at work tomorrow. Thanks for your reply. 

 

(It’s supposed to be vacuum driven when in gear below 5500 RPM) (plop).

I’ve not read the FSM yet for anything, but is that the official procedure?  I can see how the earlier idea of a visible test light checked under load and moving would verify if the valve was actuating. I’m skeptical of simply disconnecting the side stand switch and revving it giving good test results though. 

Link to comment
Share on other sites

  • Member Contributer
42 minutes ago, VARIABLE9 said:

I’ve not read the FSM yet for anything, but is that the official procedure?  I can see how the earlier idea of a visible test light checked under load and moving would verify if the valve was actuating. I’m skeptical of simply disconnecting the side stand switch and revving it giving good test results though. 

Hi Variable.

Not the Sidestand but the Neutral Switch. Guess it's a Honda safe method of telling the ECM the bike is in gear. It is mentioned in the manual to do this for testing the system.

Cheers

Link to comment
Share on other sites

  • Member Contributer

I can confirm that I have performed the test as described (centrestand/neutral/neutral wire off/tank raised) and I can visually see the flapper opening and closing as expected at around 5500rpm on my 5G. If you are confident in the wiring configuration driving the solenoid, I can't see why that would not be a valid electrical test as well. From my 5G manual it does appear that when voltage is applied to the solenoid, it opens the vacuum circuit which closes the flapper. 

 

I agree that you should see 12v across the two terminals in the connector when the flapper should be closed (<5500 rpm, in gear).

Link to comment
Share on other sites

  • Member Contributer
1 hour ago, Grum said:

Hi Variable.

Not the Sidestand but the Neutral Switch. Guess it's a Honda safe method of telling the ECM the bike is in gear. It is mentioned in the manual to do this for testing the system.

Cheers

Got it - I misstated it. I meant whatever testing Urban had been conducting. Thanks too Terry for your feedback. 

Link to comment
Share on other sites

2 hours ago, Terry said:

I can confirm that I have performed the test as described (centrestand/neutral/neutral wire off/tank raised) and I can visually see the flapper opening and closing as expected at around 5500rpm on my 5G. If you are confident in the wiring configuration driving the solenoid, I can't see why that would not be a valid electrical test as well. From my 5G manual it does appear that when voltage is applied to the solenoid, it opens the vacuum circuit which closes the flapper. 

 

I agree that you should see 12v across the two terminals in the connector when the flapper should be closed (<5500 rpm, in gear).

It’s only a two second video but as shown the solenoid / switch works. It’s the wiring.... GREATTTTT. Thanks 🙂

Link to comment
Share on other sites

  • Member Contributer
50 minutes ago, Urbanengineer said:

It’s only a two second video but as shown the solenoid / switch works. It’s the wiring.... GREATTTTT. Thanks 🙂

B814EB8B-765A-496D-A849-A527220EE98E.MOV

Hi Urban.

Can't see any video but can hear the control valve clicking, sounds like its possibly functioning ok.

This doesn't mean you have a wiring issue just yet! Have you confirmed that with Ignition On, you have a solid 12v on one of the plug pins for the control valve plug relative to ground as mentioned? If NOT then you have a wiring issue. AND until you satisfy the conditions for the ECM to enable the system you will not see the switched ground on the other pin on the plug.

Why not now just apply an external, temporary 12v to the control solenoid and with the engine running you should be able to see the Flapper CLOSE when you energise the control valve. this will verify the system is working, with the exception that the ECM is out of the loop.

Link to comment
Share on other sites

Good call! I’ll do that test when I put the bike back together. For now it’s coming apart to put all the valve clearances back to what they were before I adjusted them. 

 

I specifically wanted to see if the control valve worked and looks like that is a success. Now to do the test you mentioned and go from there. I did break the multimeter cable so I have to go buy another one after testing the valve lol. That’s the luck I have.

 

i really appreciate you following this thread and helping me!

097D28AC-148E-46D5-93CB-56657C8FF93A.jpeg

Link to comment
Share on other sites

  • Member Contributer

Hey Urban, that four way junction looks a little shabby. Make sure it's all good electrically and be Very sure it's well insulated. If that junction ferrel touches frame = Zappo, you have a DEAD bike. Sure hope you get those valves correct, third time lucky hey!

 

Link to comment
Share on other sites

  • 3 weeks later...

Yeah, flapper vacuum device definitely works, lol. This is why there is a one way valve in the line haha. 

 

For some reason the 12V signal isn’t heading to the flapper solenoid. 

 

The reason the flapper exists per my engineer buddy is that low intake air volume is good for low speed while high intake volume is good for high speed.

 

Remember how the R6 got variable length runners around 2008 or so and drastically changed horsepower output? Variable is GOOD!

 

so I want my flapper working so it can operate as close to OEM as possible. Also so it doesn’t run as lean at Low RPM’s, the major issue I’m having. 

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

By using this site, you agree to our Privacy Policy.