[Monster Mike]

PROBLEM SOLVED--SEE LATER POST
Previously did AIS removal. Did VBAK yesterday. Immediately noticed bike started roughly and than continuously surged at idle between 1000 and 1200 rpm. Test rode bike. Surging very badly at low speeds. Roll on very abrupt. Backfiring. Accelerates from mid-rpms to upper OK but still not right. Checked all connectors, hose connections---everything looks good. I previously capped the left throttle body nipple when doing the AIS removal--that is the ONLY nipple or port that I blocked. I have not made any adjustments and plan to do the Ivan Flash. Is this normal when doing the VBAK mod and will the Flash fix it? Perhaps I overlooked something when doing the VBAK---what should I be checking for? Running PCS Roadster exhaust with their Vortex race baffle (almost straight pipes). I never did disconnect any of the three sensors or their hoses--just unbolted them, pulled them aside, then zip-tied them in place. Bike ran perfectly before I did the VBAK. Any advice or suggestions greatly appreciated.

 

[catchinganupshift]

Here are the instructions from ChurchKey.

Maybe take a quick peek to make sure everything is connected/disconnected?

 

[Monster Mike]

Here are the instructions from ChurchKey.

Maybe take a quick peek to make sure everything is connected/disconnected?

I've taken multiple, multiple peeks at everything. Even went so far as to disconnect/reconnect all the sensors (even though I never disconnected them in the first place.) Checked spark plug wires, coil wires. This is driving me crazy---makes no sense.

 

[Skandix]

Without a Fuel management device or Ivan's Flash you are running lean. You can reduce intake, by restricting your filters, until you get a fuel management system.

 

[Monster Mike]

Without a Fuel management device or Ivan's Flash you are running lean. You can reduce intake, by restricting your filters, until you get a fuel management system.

I have the Cobra Fi2000 Black blue tooth model. I'm also getting Ivans Flash whether I need it or not. After I completed the VBAK I first ran it with the Cobra--problems as indicated above. Disconnected it and ran stock connections---got worse. I thought that the Cobra unit would have adjusted at least somewhat for the VBAK, exhaust , and AIS removal. No? I guess I'll need to play aroud with the bluetooth adjustments to see if I can make an improvement. The bike is not drivable as it is.

 

[Churchkey]

Check sensor wiring.
The Grey sensor wire connector connects to the black sensor with the vacuum hose to the throttle body for the front cylinder.

The black sensor connector with the PINK & WHITE wire connects to the black sensor with the vacuum going to the throttle body for the rear cylinder.

The black sensor connector with the PINK WIRE goes to the atmospheric pressure sensor. No vacuum cap or hose on this sensor.

The fuel pressure valve vacuum port needs to be open to the atmosphere.

Installing an air kit will not make the bike run lean @ idle or any other time with the exception of full throttle.
Try eliminating the LCV, remove both large hoses from the throttle bodies & cap each port separately.

Is the CEL illuminated? If so what are the problem code #'s.

Post results.
Luck

 

[Monster Mike]

Check sensor wiring.
The Grey sensor wire connector connects to the black sensor with the vacuum hose to the throttle body for the front cylinder.

The black sensor connector with the PINK & WHITE wire connects to the black sensor with the vacuum going to the throttle body for the rear cylinder.

The black sensor connector with the PINK WIRE goes to the atmospheric pressure sensor. No vacuum cap or hose on this sensor.

The fuel pressure valve vacuum port needs to be open to the atmosphere.

Installing an air kit will not make the bike run lean @ idle or any other time with the exception of full throttle.
Try eliminating the LCV, remove both large hoses from the throttle bodies & cap each port separately.

Is the CEL illuminated? If so what are the problem code #'s.

Post results.
Luck

ChurchKey THANKS! Yes--all three sensors are connected correctly. I removed the center LCV hose--I checked it with my finger ---it was sucking air----didn't change idle. I will do the LCV check as you suggest and post the results in the morning. No error codes at all. CEL not illuminated. Driving me nuts!

 

[arizonawarrior]

Due respects, if your Beast was fine prior and immediately after you observed what you posted, and if you did no other work on the bike, then Churchkey is correct. Although you said you did not remove the hoses or connectors. So let's revisit everything as if hoses and connectors did get pulled, just so any oddity or damage might become more visible. I would expect a CEL if a wire were damaged. But vacuum hose damage or position swapping does not generate a CEL or Er code.

Here is a help file with pictures that helps. If you clear your mind and compare the correct placements, then hopefully you can correct it.

It seems like 99% of the time when this situation is posted, its the vacuum hoses. In rare cases it has to do with the LCV but that doesn't strike me as the culprit here based on your posts.

Warrior Modifications How-To: Beginners

This area is a storehouse for Beginner's Modification help screens. 1. This Table of Contents. 2. Problems After VBAK/BAK or Ignition Coil Relocation. 3. Selecting and Installing Aftermarket Fuel Dry Breaks. 4. Turn Signal Fast-Flash and Click of Death (COD) Solutions. 5. AIS Bracket...

www.rswarrior.com

Download the pdf at the link above. You already know Jug1 is the rear jug and it's intake slants over the front jug (2).

Check for broken cracked kinked reversed hoses. Check that the AMBIENT air sensor has NO HOSE. Compare the wire colors at the connectors. Check if other surrounding hoses were dislodged damaged.

I've also attached the pdf help file here in case helpful. It's the same help file linked, and can be tracked-down later by using the Table of Contents in the Documentation forum.

Note the plugs are all the same, so any of these three sensors can plug into any of the three connectors.

If you still have the same trouble then I don't know where to point you, based on your posts here. Luck brother.

 

[BlazinWarrior]

I believe you gotta hook up the Cobra tuner and go take it for a nice WOT ride..give it all the beans and let the cobra work and adjust. It won't be perfect on the first ride but it will make mirco adjustments. It will get better. I have the tuner and had no issues with it. I'm going to be getting ivans flash as well and I've heard it runs really good with the flash and cobra tuner together.

 

[arizonawarrior]

It is for certain a magic combination of advanced technologies ☠ but unlikely to fix the trouble posted

 

[BlazinWarrior]

What year is your bike? Check this link Yamaha Consumer Publications to see if your VIN brings up any recalls for your bike. Depending on the year there were CPS (pick up coil sensor) and TPS (throttle position sensor) recalls. Both of which cause all type of weird symptoms. I had personally had a CPS recall that I didn't know about til I check that website and confirmed the weird symptoms I was having which started out of nowhere one day and had me chasing all types of things (bike was at 12k miles before it started failing). Changed it and never had a single problem again. You may have just got unlucky and the recall showed it's face at the same time you did the vbak which is now making it seem like the vbak is your problem or hoses around it. Just my 2 cents.

 

[Skandix]

From what you have stated "I first ran it with the Cobra--problems as indicated above. Disconnected it and ran stock connections---got worse" would indicate that the Stock ECU is not up to the task of handling the Extra Air that VBAK gives. The Cobra is helping to a degree, indicating Fuel increase helps. Won't hurt to try BlazinWarrior suggestion and confirm what others have posted.

 

[Monster Mike]

From what you have stated "I first ran it with the Cobra--problems as indicated above. Disconnected it and ran stock connections---got worse" would indicate that the Stock ECU is not up to the task of handling the Extra Air that VBAK gives. The Cobra is helping to a degree, indicating Fuel increase helps. Won't hurt to try BlazinWarrior suggestion and confirm what others have posted.

Here is what I did this morning. As ChurchKey suggested: I disconnected the two outside hoses running from the LCV to the two intakes. I started the engine----no change --still surging at idle 1100 -1250 rpm. I then plugged the two hoses---idle immediately settled down to an slightly UNEVEN 1000-1100 rpm. Took it for a 5 minute test ride--never got the bike up over 45 mph. On the way out--Much better---very little surging---still a little abrupt on-off throttle. At my turn-around point I adjusted the throttle back down to 1000 rpm and rode back home. On the trip the bike seemed to be running perfectly---no surging--still just a little abrupt on-off throttle (which I've always had). By the time I got back to the garage the idle was rock steady at 1000 rpm and the bike seemed to be running as it normally did prior to doing the VBAK. So --ChurchKey & Arizona ---Does this mean that I can ditch the LCV?(I have no issue with waiting a minute or so for warm-up). I seems that the Cobra fuel manager was making some adjustments on the ride. I'll know more when I can take it for a more comprehensive test ride this ebvening and put it through its paces from idle, low speed lugging, to WOT. Ill post the results here.

 

[Monster Mike]

What year is your bike? Check this link Yamaha Consumer Publications to see if your VIN brings up any recalls for your bike. Depending on the year there were CPS (pick up coil sensor) and TPS (throttle position sensor) recalls. Both of which cause all type of weird symptoms. I had personally had a CPS recall that I didn't know about til I check that website and confirmed the weird symptoms I was having which started out of nowhere one day and had me chasing all types of things (bike was at 12k miles before it started failing). Changed it and never had a single problem again. You may have just got unlucky and the recall showed it's face at the same time you did the vbak which is now making it seem like the vbak is your problem or hoses around it. Just my 2 cents.

Thanks---I will check that out.

 

[arizonawarrior]

What year is your bike? Check this link Yamaha Consumer Publications to see if your VIN brings up any recalls for your bike. Depending on the year there were CPS (pick up coil sensor) and TPS (throttle position sensor) recalls. Both of which cause all type of weird symptoms. I had personally had a CPS recall that I didn't know about til I check that website and confirmed the weird symptoms I was having which started out of nowhere one day and had me chasing all types of things (bike was at 12k miles before it started failing). Changed it and never had a single problem again. You may have just got unlucky and the recall showed it's face at the same time you did the vbak which is now making it seem like the vbak is your problem or hoses around it. Just my 2 cents.

His bike is a 2007 and I considered suggesting recall status also. However he posted his bike ran perfectly until the moment he installed his VBAK. That suggests to me his recalls were done or are otherwise not the trouble plus the posted symptoms seem to vary a bit from what many here reported over the years.

I also considered that his aftermarket exhaust might have been restricted below it's full capacity to flow by the stock intake system. And installing the VBAK therefore created very lean air:fuel. That might account for the unusual backfiring mentioned (which seems to have not been there prior based on how its mentioned here). In any event, that is a separate thing from surging. Plus it's impossible to know what is meant by 'abrupt' as used here. I expect it's really sharper throttle response making the stock engine braking more apparent, but I'm not at the bike (Ivan's would fix this assuming my guess is correct).

So there are several separate issues all reported as having appeared at the moment of VBAK install. That makes no sense considering the bike was reportedly running perfectly the moment before. This is why I suggested starting over. There would need to be a couple things gone wrong magically all at the same moment to cause these various symptoms at the same moment.

I'm very interested in learning what the solution turns out to be. I wish I had better suggestions. If it were me, I would retrace the work, then I would begin structured troubleshooting of the bike to assure baseline settings are all correct. Meaning Air, Fuel, Spark, Sensors (in that order). What ever the troubles are, they are simple fixes that are hard to notice. And very likely are in the areas of the VBAK install.

 

[Skandix]

Great response ArizonaWarrior!

 

[Monster Mike]

I believe you gotta hook up the Cobra tuner and go take it for a nice WOT ride..give it all the beans and let the cobra work and adjust. It won't be perfect on the first ride but it will make mirco adjustments. It will get better. I have the tuner and had no issues with it. I'm going to be getting ivans flash as well and I've heard it runs really good with the flash and cobra tuner together.

I have no problems with the Cobra tuner. Cobra states that some air intake and exhaust mods are outside the parameters that their unit can self-adjust too. I think that is the case here (as Arizona says in his post).

His bike is a 2007 and I considered suggesting recall status also. However he posted his bike ran perfectly until the moment he installed his VBAK. That suggests to me his recalls were done or are otherwise not the trouble plus the posted symptoms seem to vary a bit from what many here reported over the years.

I also considered that his aftermarket exhaust might have been restricted below it's full capacity to flow by the stock intake system. And installing the VBAK therefore created very lean air:fuel. That might account for the unusual backfiring mentioned (which seems to have not been there prior based on how its mentioned here). In any event, that is a separate thing from surging. Plus it's impossible to know what is meant by 'abrupt' as used here. I expect it's really sharper throttle response making the stock engine braking more apparent, but I'm not at the bike (Ivan's would fix this assuming my guess is correct).

So there are several separate issues all reported as having appeared at the moment of VBAK install. That makes no sense considering the bike was reportedly running perfectly the moment before. This is why I suggested starting over. There would need to be a couple things gone wrong magically all at the same moment to cause these various symptoms at the same moment.

I'm very interested in learning what the solution turns out to be. I wish I had better suggestions. If it were me, I would retrace the work, then I would begin structured troubleshooting of the bike to assure baseline settings are all correct. Meaning Air, Fuel, Spark, Sensors (in that order). What ever the troubles are, they are simple fixes that are hard to notice. And very likely are in the areas of the VBAK install.

Spot on! Not fixed but I think my trouble shooting is making some headway. This afternoon started the bike and let it warm up for about a couple of minutes. Both hoses from LCV to intakes disconnected and plugged. At first the bike idle was perfect at 1000 rpm. Then suddenly rpm dropped to almost nothing--bike cut off. Started it again with popping and hard start. Had to keep the revs up to keep it running. Took it out on the road for a test because I wanted to see how it performed with LCV hoses blocked. Would hardly run, no power, had to keep revs up to keep it running. It felt like it was running on ONE CYLINDER! Got back to garage and unplugged the hoses. With the engine running I then put my finger over the end of the hose that goes to the front cylinder---no change. Then I did the same with the hose that runs to the rear cylinder---the engine immediately almost cut off. Hmmmm! One cyl working the other one not? I then started checking out my Dyna coils (I had previously experienced a shorting issue when I first installed them.) I felt the left coil feeding the rear cyl---stone cold. Then I felt the right coil feeding the front cyl---so hot I could barely hold my hand against it. Pulled the plug wires to the rear cyl --engine would not fire. Pulled the plug wires to the front cyl (with rear cyl plugs hooked up)---fired right up. CONCLUSION?? I think I have a bad Dyna coil.

 

[arizonawarrior]

A vtwin running on one cylinder presents symptoms different than those you originally described. So if a primary coil wire is failed or damaged or shorting (or if a very solid coil has somehow failed in an instant) then that trouble is separate from your symptoms posted in your original post.

Before making assumptions, swap your coils and see if the symptom swaps too. I expect you'll stumble across the trouble during that physical swap. Then you can get back to your original post's symptoms.

 

[Monster Mike]

A vtwin running on one cylinder presents symptoms different than those you originally described. So if a primary coil wire is failed or damaged or shorting (or if a very solid coil has somehow failed in an instant) then that trouble is separate from your symptoms posted in your original post.

Before making assumptions, swap your coils and see if the symptom swaps too. I expect you'll stumble across the trouble during that physical swap. Then you can get back to your original post's symptoms.

A vtwin running on one cylinder presents symptoms different than those you originally described. So if a primary coil wire is failed or damaged or shorting (or if a very solid coil has somehow failed in an instant) then that trouble is separate from your symptoms posted in your original post.

Before making assumptions, swap your coils and see if the symptom swaps too. I expect you'll stumble across the trouble during that physical swap. Then you can get back to your original post's symptoms.

Arizona, As usual you are correct. Swapped out the coils---they are both working. When I first installed the Dyna coils I experienced a short to the coil bracket--I found the short by unbolting the coils from the brackets and no more short--no more blown fuses. I just now removed both coils from their brackets and just hung them loose to the side. Engine started right up, perfect 900 rpm idle, instant throttle response. I think I may have had an intermittent coil shorting out problem--therefor the varied symptoms. It's to late here in Virginia for a road test but will do first thing in the morning and post the results. (Keeping my fingers crossed!)

 

[arizonawarrior]

On my DC2-1 install, I used stainless button head Allen's to affix the bracket to the bike, and the coils to the bracket. It created just enough gap to stop arcing. A dark garage, or night, helps inspect for arc.