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If you DeCat

27132 Views 13 Replies 7 Participants Last post by  Newbie790
Sectional photo of the Cat Converter.

By removing this completely, and replacing with an available pipe:

*What changes should be made to compensate for this as well as the slip-on?

*Coober doesn't recommend removing the Cat, why? How will it affect the running with the Coober installed?

Thanks for your responses.

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In simple terms, not many here have done that yet, so it's open to discussion.

Basically you're adding more air/less fuel to a machine that's already running lean at the bottom end. Potential for things like stalling at lights and poor low speed running.
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In simple terms, not many here have done that yet, so it's open to discussion.

Basically you're adding more air/less fuel to a machine that's already running lean at the bottom end. Potential for things like stalling at lights and poor low speed running.
Of for sure you are correct. I'm just wondering that if I go this route, how to compensate for the increase in A/F?

I dropped a note to Coober, so hopefully I'll get an idea to post up sooner.
This is what Wings say.
Regarding the de-cat pipe you must know that the new 790 Duke engine was designed from
scratch to operate with a catalytic converter. All components were designed accordingly and
removing the cat could have consequences. Instead of running with the Air Fuel Ratio of
14.7 ,which is the optimum, the engine will run at an AFR of 18.8, which is extremely lean. This
means thermic problems and durability issues. If you let the bike run at idle for 20 minutes with an
AFR of 18.8, the engine would be seriously damaged. Besides this, removing the cat contributes
nothing in terms of power and torque.
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This is what Wings say.
Regarding the de-cat pipe you must know that the new 790 Duke engine was designed from
scratch to operate with a catalytic converter. All components were designed accordingly and
removing the cat could have consequences. Instead of running with the Air Fuel Ratio of
14.7 ,which is the optimum, the engine will run at an AFR of 18.8, which is extremely lean. This
means thermic problems and durability issues. If you let the bike run at idle for 20 minutes with an
AFR of 18.8, the engine would be seriously damaged. Besides this, removing the cat contributes
nothing in terms of power and torque.
That's good intel, thank you B.
You should be fine with a Powercommander slapped on. No top end power gained but fairly significant bottom end gained.
And compared to bone stock the bike should run just way smoother.

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You should be fine with a Powercommander slapped on. No top end power gained but fairly significant bottom end gained.
That's great to hear. I'm not concerned with more HP. Increased Torque, h e l l yea!

I guess one aspect is, don't R&R the Cat until you get 'er tuned.
You should be fine with a Powercommander slapped on. No top end power gained but fairly significant bottom end gained.
And compared to bone stock the bike should run just way smoother.

https://www.youtube.com/watch?v=-lY8fRJoff0

with check engine light permanently on.

We have two 790 in our group with rotweiler on it.
Both with check engine light. Now the guys fight to get the money back.

They have now install the akrapovic mapping.
No performance gain at all, but also no check engine light and all the drive mode features stay active.
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with check engine light permanently on.

We have two 790 in our group with rotweiler on it.
Both with check engine light. Now the guys fight to get the money back.

They have now install the akrapovic mapping.
No performance gain at all, but also no check engine light and all the drive mode features stay active.
Well that's not the best news. What's Rotweiler's take on it?
with check engine light permanently on.

We have two 790 in our group with rotweiler on it.
Both with check engine light. Now the guys fight to get the money back.

They have now install the akrapovic mapping.
No performance gain at all, but also no check engine light and all the drive mode features stay active.
Doesnt seem to be a no-fix permanent solution though but instead a temporary problem though.


"NOTE: With the purchase of a Powercommander from Rottweiler Performance we offer the O2 Optimizers for free below.
As of 4/23/19 we have dongles available, and they will work to keep the stock ECU from overwriting the PCV tune, but the engine light will go on. If you opt for a free set, that is all we have for now and will not replace this set with a free set once we have found a solution. We are making them available for customers who need them for racing or for tuning, but are willing to live with the engine light until we find the solution. "

O2 delete sensors that is causing the problem at the moment.


I will get it regardless of the light because you have tree different maps to choose from, standard setup, open slip-on and full system and easier to deactivate for the inspection.



EDIT:

"NOTICE: As of 4/21/19 we have achieved defeating the closed loop portion of the stock ECU for the purposes of running our 790 Duke Powercommander V maps and holding the tune perfectly, but we have not been successful in keeping the engine light off on every bike which we are still working on.
We are keeping these online and available for racers who are in need of them and do not mind the engine light being on for the time being, but want to notify our customers as such until we find a solution to the engine light.

We have decided to discount these parts 50% until we find the solution to the engine light but no refunds will be issued once a solution is found and if purchased at this discount.
All customers who purchased before this date will receive a credit for the solution or a replacement set if costs are roughly the same. "
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Doesnt seem to be a no-fix permanent solution though but instead a temporary problem though.


"NOTE: With the purchase of a Powercommander from Rottweiler Performance we offer the O2 Optimizers for free below.
As of 4/23/19 we have dongles available, and they will work to keep the stock ECU from overwriting the PCV tune, but the engine light will go on. If you opt for a free set, that is all we have for now and will not replace this set with a free set once we have found a solution. We are making them available for customers who need them for racing or for tuning, but are willing to live with the engine light until we find the solution. "

O2 delete sensors that is causing the problem at the moment.


I will get it regardless of the light because you have tree different maps to choose from, standard setup, open slip-on and full system and easier to deactivate for the inspection.



EDIT:

"NOTICE: As of 4/21/19 we have achieved defeating the closed loop portion of the stock ECU for the purposes of running our 790 Duke Powercommander V maps and holding the tune perfectly, but we have not been successful in keeping the engine light off on every bike which we are still working on.
We are keeping these online and available for racers who are in need of them and do not mind the engine light being on for the time being, but want to notify our customers as such until we find a solution to the engine light.

We have decided to discount these parts 50% until we find the solution to the engine light but no refunds will be issued once a solution is found and if purchased at this discount.
All customers who purchased before this date will receive a credit for the solution or a replacement set if costs are roughly the same. "


This is exactly what the guys from coober told me months ago. It's not going to work with a dongle
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Correct me if i´m wrong here but isnt the Coober and subsequently the ATOM technically a power commander except it contains no O2 dongles?
Which means that in the closed loop system the ECU will do whatever it wants since it will compensate for whatever the Coober/ATOM/PC try to change with fuelling due to it being able to read the O2 sensors?
3
Convo with Coober the other day..

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Hello all, just signed up and I'm having issues. Check engine just came on.
Here's the mods: cat delete, Booster Plug and K&N. Has a slight miss on initial throttle opening now too.
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