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Discussion Starter #1
I just purchased a BODIS slip-on exhaust for my 2010 F4, it comes without the valve that the stock slip-on has on it. I would like to know how to eliminate the mechanism that modulates that valve open and closed. It seems like I have to remove the cables from the electric motor (servo) and just leave the electric motor in its place functioning electrically. If I remove the motor altogether, it will confuse the computer thinking the motor went bad, causing CHECK ENGINE LIGHT or worst. If anybody out there has done this modification or knows what is the correct way to do it, I would greatly appreciate the help.

Thanks,
Lou
:f4: :yo:
 

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eliminating servo motor?

what diagnostic tool does a '10+ MV use? is it still the VDST?
deleting the motor is probably possible......you might need a password like with Aprilia's Axone/Navigator from Texa:naughty::naughty:

try contacting TechnoResearch:)
 

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Removing the valve will change the A/F mixture in the RPM range where it is active. I assume it would be a drastic change to super lean. That valve acts in conjunction with the mapping of the ecu to provide power with lower emmisions in the lower RPM region...as I understand it...(I know the smart guys will chime in if I'm wrong here).

Were it me, I'd leave the motor alone, disconnect the cables that move the valve and call it a day.

I'd expect that I'd have to tune the ECU for operation without the exhaust valve.....or I'd expect problems.

Where does the Bodis "Slip On" connect to the current exhaust? It appears from the photo that it connects just upstream of the exhaust valve...
 

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Most exhaust tuning valve removals require installing a stopper on the actuator to simulate the cables reaching full open or closed, fooling the ECU to think it is still functioning (Kawasaki ZXRs as example), or the disabling of the circuit inside the ECU (Suzuki GSX-R's have a ground wire from the ECU that can be clipped taking that system out). Some ECUs will never know the cables aren't connected anymore as the actuator works from a center point (Yamaha R1-R6 I believe)......Not sure how the MV system works, but the exhaust manufacturer should provide instruction....either that or they anticipate you will be using a different ECU (race kit or Microtech).

Regardless, simply unplugging and yanking the actuator motor off will cause a detected trouble code and resultant Engine Malfunction Light (check engine)...possibly go to a default fail safe fuel map as well. Just disconnecting the cables may as well.

Sorry, I don't have an answer for this one. Hopefully someone will enlighten us.
 

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just remove the cables and it will be fine. you can do it on a stock set up as well and you won't get an engine light.
 

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There you go....the Actuator must work off a center point (ala Yamaha)....but you can't pull off the actuator itself without getting a Detected trouble code.
 

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Discussion Starter #9
thanks for all the input. What I ended up doing which was recommended by Speers Racing the manufactures of the BODIS exhaust is disconnecting the cables from the electric motor and removing them with the stock slip-on. Works great run beautiful! I'm very happy with the results.

Thanks,
Lou
 

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?

thanks for all the input. What I ended up doing which was recommended by Speers Racing the manufactures of the BODIS exhaust is disconnecting the cables from the electric motor and removing them with the stock slip-on. Works great run beautiful! I'm very happy with the results.

Thanks,
Lou
so from that i guess there is no problem if you leave the electric motor connected, i'm surprised that there isn't a password protected way to delete the motor without triggering an error code or going into limp mode

primitive POS.......it would appear that MV is a ways behind the curve:naughty:
with my '03 built Aprilia RSVR......to delete the 02 sensor, you plug the diagnostic tool put in the password and delete the 02 sensor......avoiding the error code and limp mode:naughty:
 

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Just curious, why do you want to remove the valve system? As I understand this assists with low and mid range torque at the cost of noise, isn't that torque a bit more important?

Or am I mis-guided?

Cheers :smoking:
 

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Sounds great without it if you can pick any loss of performance you are a better man than me!
 

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so from that i guess there is no problem if you leave the electric motor connected, i'm surprised that there isn't a password protected way to delete the motor without triggering an error code or going into limp mode

primitive POS.......it would appear that MV is a ways behind the curve:naughty:
with my '03 built Aprilia RSVR......to delete the 02 sensor, you plug the diagnostic tool put in the password and delete the 02 sensor......avoiding the error code and limp mode:naughty:
Doesn't Yamaha, Honda, Suzuki, et all use the same...or very similar set up?
 

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Suzuki is the only manufacturer i know of that has a provision to clip a wire and pull the entire system (for race purposes). Multiple ground wires from the ECU attach to different circuits inside...just have to know which one does what.

For street riding, the exhaust tuning valve does help smooth the torque curve and power delivery. You may not feel it if you aren't a factory test rider or Valentino Rossi, but you can see it on the dyno chart. For racing use it becomes added weight and disruption in air flow because race bikes are run at the top of their power curve all the time (if you are a fast guy) so that smoother torque curve down in the bottom 1/3rd isn't helpful.

Cam timing overlap is the reason the tuning valves are there. For big power (rpms) you need a lot of overlap, but then you end up loosing some fresh charge into the exhaust at certain lower rpms and actually can get reversion in the intake tract (where the air flow momentarily stops). Tuning the exhaust pressure waves helps correct this. 2-stroke expansion chambers are built on this principal. You can build 2 different shaped pipes for the same 2-stroke engine with one providing good low end and one providing good top end just based on pressure wave timing. Yamaha pioneered a variable tuning valve in the exhaust port of their 2-stroke race bikes (the Power valve) to get both low and top end power from the same pipe (pretty much all 2-stroke race bikes ended up with a variation of this).....same theory applies to 4-strokes.

So, unless you are racing, you are better off keeping the tuning valve.....of course, it would be helpful to be able to adjust it if you change cams or alter the air flow characteristics in the exhaust (free flow muffler?).....but the amount of dyno time required to get it right might wear out your engine (and wallet).
 

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Sounds great without it if you can pick any loss of performance you are a better man than me!
power delivery in the earlier RPM's as even and predictable as we've grown to love?

It was comments to that end that skewed me away from disconnecting it. I kinda think I'm better off, dissecting the stock exhaust and figuring out a way to do a mod similar to yours on them.

After all why else would i learn how to weld SS?
 

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Ditch the valve. You'll never know it is gone, especially if you slap an RG4 ecu or X-bikes ecu in there. The hassle of trying to retrofit it is not worth it, IMO.

My 2010 has the RG4 system (full) on it.
 
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