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Discussion Starter #1
Fitted my new exhaust From brspecialtuning today looks tidy and didn't take to long. The only problem both hooks pulled out of the springs, no stretch in the springs at all so ordered some 75mm exhaust springs of ebay. now for the tail tidy will I be needing indicator heat shields ?
 

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Fitted my new exhaust From brspecialtuning today looks tidy and didn't take to long. The only problem both hooks pulled out of the springs, no stretch in the springs at all so ordered some 75mm exhaust springs of ebay. now for the tail tidy will I be needing indicator heat shields ?
well several people have melted the rear indicator on 790's
I suppose it will depend upon the tail tidy of your choice and how much clearance there is
 

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now for the tail tidy will I be needing indicator heat shields ?
Comparing the positioning of the stock exhaust with that of the Ixil M2, the Ixil appears to be a lot shorter. I'd be surprised if it would be close enough to the indicator to do any damage. It may not even be in line with it.
 

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Hi,
I'm thinking to buy this exhaust. Good looking and sound nice from youtube videos.

There is another option with similar styling, the Austin Racing exhaust, it's a titanium exhaust not homologated and it's overpriced in my opinion.

Can you review us your exhaust?
 

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Discussion Starter #5
It does come with a euro 4 compliance certificate, waiting for the salt on the roads to stop being put down then I will be out on the roads.
 

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It does come with a euro 4 compliance certificate, waiting for the salt on the roads to stop being put down then I will be out on the roads.
It's probably the one I'm going to get too. I'm in Vancouver, and having a problem finding an Ixil dealer here (or at least a dealer who will reply to my e-mails!) I could buy from the UK, but I'd likely get slugged for import duty etc. Think I'll end up buying from Ixil USA, having it shipped to Washington State, then picking it up from there. Roger, looking forward to your review on it, and hopefully a sound clip!
 

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If it's been known for a long time, this loss of power caused by the Ixil M2 on the 790 Duke must be documented somewhere. Couldn't find anything online about it. Anybody else found this an issue?
usually just different manufacturers slagging each other off, but they can’t actually publish anything because reasons.
 

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usually just different manufacturers slagging each other off, but they can’t actually publish anything
Could be. Without seeing dyno results, I'm a little skeptical about claims of power loss. Possibly if it's run with the baffles removed, but unlikely otherwise. Looking forward to the OP's findings.
 

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If it's been known for a long time, this loss of power caused by the Ixil M2 on the 790 Duke must be documented somewhere. Couldn't find anything online about it. Anybody else found this an issue?
So Coober says any slip ons that are straight lose power, basically bigger they are the less they lose(so like Akra, Wings, SC1-R etc don't lose). Could be cause they sell a kit with Wings, not sure. I haven't seen anyone else say that and coober won't release dyno sheets. Austin Racing says their slip on gains. Rottweiler says stock and Yoshimura(yet released but looks like a thinner pipe from the back) have plenty of power to gain right off the bat. I haven't dyno'd mine with S1 but isn't noticeable if it is a loss.
 

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So Coober says any slip ons that are straight lose power, basically bigger they are the less they lose(so like Akra, Wings, SC1-R etc don't lose). Could be cause they sell a kit with Wings, not sure. I haven't seen anyone else say that and coober won't release dyno sheets. Austin Racing says their slip on gains. Rottweiler says stock and Yoshimura(yet released but looks like a thinner pipe from the back) have plenty of power to gain right off the bat. I haven't dyno'd mine with S1 but isn't noticeable if it is a loss.

The cat offers a lot of back pressure
The baffle very little

I have a coober fitted and i have tried many options cat on off, baffle in out, akra and standard

Best sound no baffle no cat, a bit loud for me however
I have settled upon cat in, Akra with baffle out.

Regarding performance
My Cobber map was designed for cat in, the coober does improves smoothness which is why i fitted it.
Power output hmmm.
AR use a coober unit with a different map and no cat, which does show a power gain.

For me smoothness and sound was what i wanted and i really did not care that much about extra power, but did not want to lose power particularly in the mid band.

Someone needs to spend a couple of days on the same dyno with the same bike trying the options for a real comparison
 

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If it's been known for a long time, this loss of power caused by the Ixil M2 on the 790 Duke must be documented somewhere. Couldn't find anything online about it. Anybody else found this an issue?
I found an Italian youtube video and in the comments, there are people debating on this subject.


As I understood, people are saying that if you de-cat the KTM790 without remapping we actually lose power and reliability.


If I buy this slip-on I will put my 790 on a dyno run :D
 

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I found an Italian youtube video and in the comments, there are people debating on this subject.




As I understood, people are saying that if you de-cat the KTM790 without remapping we actually lose power and reliability.


If I buy this slip-on I will put my 790 on a dyno run :D
it will be interesting to see
 

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Guys,
I found "GOLD MATERIAL" in COOBER website, dyno runs comparing:
- KTM790 Stock vs KTM790 COOBER
- KTM IXRACE vs KTM790 IXRACE_COOBER

Let's look at the dyno run: KTM790 Stock vs KTM790 COOBER
- The NW scale after the 50NW start to change, the 60NW now are at the middle of both lines, 70NW a little higher and so on! Meaning that the top NW is actually 90 now 80! Or I'm seeing this wrong?!

Let's look at the dyno run: KTM IXRACE vs KTM790 IXRACE_COOBER
- There are no scales! Sound suspicious to me!
- The power drops at 9400/9500RPMs in the other dyno the bike hit the top power at 10200RPMs. The same logic can be applied to torque lines. Looks to me, that in this dyno the RPMs are actually 1000RPMs lower than really is!

I will try to analyse this runs more deeply and try to make sense out of it but at my first glace, looks to me that the slip-on actually produces more power than the stock!
I belive, different dyno runs can reach different numbers but without so much deviation.

Conclusion: They are trying to fool us! :mad:

Links bellows:
KTM 790 DUKE - COOBER GmbH
KTM 790 DUKE EU KIT - COOBER GmbH
 

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My professor at university would say: conclusion is, you should spend more money on your education instead on a motorcycle, before doing a conclusion. :)

we had the same topic at our local bike club few days ago. Our local dealer sold 80 Ixrace mufflers, you can imagine how hard those discussions are.
happy that there are some smart guys up there, every time happy to learn. The conclusion was less dramatic then yours.

on the IXrace chart they remove the numbers for simple reason. no permit from ixrace to show any numbers. on the chart there is 790 with ixrace mk2 muffler and 790 with ixrace mk2 and their Product. No standard 790 is shown. make sense if you are not allowed to show numbers. but, they have display the negative energy, based on the experts, this is where they look first. Also it looks like they made a simply inertia curves, this is used to show a difference, based on the information i can get, this type of dyno runs are useless to work with, its just displaying.

their standard chart is showing no negative energy, and based on the power oscillation it looks like steady setup, what i have learn, this is whats used on high accuracy dyno and used for development.


would be cool if you deep dive more in to this, i am at beginning of my education journey and very happy to learn.





Guys,
I found "GOLD MATERIAL" in COOBER website, dyno runs comparing:
- KTM790 Stock vs KTM790 COOBER
- KTM IXRACE vs KTM790 IXRACE_COOBER

Let's look at the dyno run: KTM790 Stock vs KTM790 COOBER
- The NW scale after the 50NW start to change, the 60NW now are at the middle of both lines, 70NW a little higher and so on! Meaning that the top NW is actually 90 now 80! Or I'm seeing this wrong?!

Let's look at the dyno run: KTM IXRACE vs KTM790 IXRACE_COOBER
- There are no scales! Sound suspicious to me!
- The power drops at 9400/9500RPMs in the other dyno the bike hit the top power at 10200RPMs. The same logic can be applied to torque lines. Looks to me, that in this dyno the RPMs are actually 1000RPMs lower than really is!

I will try to analyse this runs more deeply and try to make sense out of it but at my first glace, looks to me that the slip-on actually produces more power than the stock!
I belive, different dyno runs can reach different numbers but without so much deviation.

Conclusion: They are trying to fool us! :mad:

Links bellows:
KTM 790 DUKE - COOBER GmbH
KTM 790 DUKE EU KIT - COOBER GmbH
 

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this debate will never end.

we have to start with the main issue, almost no dyno's have good absolute accuracy, two dyno's will normally give very different results.

so why use a dyno?

They are normally useful for comparative (not absolute) measurements.

i.e. dyno run standard bike, then do your mods and re-run

use same dyno, same bike, same day ideally for best comparison.

then you can tell if you are gaining or losing.

you can also check your fuel air ratio
 
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