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So I recently installed a decat and am getting a PCV from Rottweiler. I live in an area with pretty consistent temps and close to almost never more than 2000ft. But am planning a big trip around the US with some really high elevation in Colorado and suff. Will I have any issues with AFR? Will I need to get an auto tune with the WBO2 sensor or can I plug the stock sensors back in and use a street map, or is it not really an issue?
 

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So I recently installed a decat and am getting a PCV from Rottweiler. I live in an area with pretty consistent temps and close to almost never more than 2000ft. But am planning a big trip around the US with some really high elevation in Colorado and suff. Will I have any issues with AFR? Will I need to get an auto tune with the WBO2 sensor or can I plug the stock sensors back in and use a street map, or is it not really an issue?
I have NOT fitted a PCV to my 790D - But do have one (with AutoTune) on my R3. And it's remapped at MAP not TPS. Remapping with MAP is a serious PITA to do. It's better but you will need masses of time to get it right.

Will you have issues? Yes.
Will they be serious? Maybe.

My understanding of the PCV solution for the 790 is that "closed loop" is bypassed. And then it's riched up by most "experts".

My R3 runs closer to just lean of Lean Best Torque for cruising RPM's - and at Rich Best Torque otherwise. Fuel consumption soared. - I can pass 10L/100kms if I am really "playful" - Usually 8.5L/100kms overall. Stock would be 7.5L/100 approx.

I live at about 770metres. Often pass 1000m and drop to 600m.

It's when I visit my mum in the UK who lives near sea level I can feel the Autotune really start to work - and ditto on returning home. ime it takes about a tank of fuel (200-250kms) for the adaption to fully complete. At sea level I am running the same AFR - but as there is more air - I use more fuel as well. NOTABLY MORE. But traffic near my mum is heavy so I tend to ride slower.


It's MANIFOLD ABSOLUTE PRESSURE that matters most. Temp variance plays a lesser role ime - ON FUEL INJECTED ENGINES.

So if you dont have an AUTOTUNE - as you go higher up - it just gets richer. You could hit lean issues at sea level.
 

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First off the higher you go the leaner the bike wants to be, there's less air so you need less gas to go with it. At sea level the bikes closed loop system would be adding more fuel to stay in proper range than it would at altitude, where there's less air to burn the fuel available. The open loop portion Of the fuel table I'm assuming still will be affected by the map sensor and intake temps to correct for elevation. the dynojet fuel controller doesn't plug into a MAP sensor on the Duke... So I don't know how it would affect the MAP readings...
 

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As far as I'm aware that's for forced induction tuning you can go down that rabbit hole with this video:
Maybe you could try and mess with the fuel in relation to MAP on an NA system but I'm pretty sure the engine management system already does this.
The minute you add a PCV - The PCV overrides what the ECU says. It is an isolated system. And unless you have Autotune it will not alter or adapt.

I have used that "Forced Induction" port for NA on the R3 - it is as you say a rabbit hole. But have Autotune. So I just say ( at pressure x vs rpm y I want AFR z) - This sounds easier than it is.

It's also why I decided to NOT mess about with the 790D. Just fitted a COOBER.

If I were fitting a PCV to the 790.
:- I'd get it dialed in properly at a GOOD local Dyno centre. If they are any good at all - they would understand where best to set the mix for over all use. Somewhere between RBT and LBT for each cell - but much of this is experience. I am sure Rottweiler have put in DYNO hours, but even so it will always be an approximation map, and not matched to an individual engine.
 
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