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Slip-ons look great but I read the smaller ones lose power, tbh I'd not get one unless I saw dyno numbers confirming it's not hurting the performance. Does anyone know of exhausts that have been tested?
 

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Slip-ons look great but I read the smaller ones lose power, tbh I'd not get one unless I saw dyno numbers confirming it's not hurting the performance. Does anyone know of exhausts that have been tested?
I’ve not seen any evidence that smaller cans cause power loss, I think it’s pub talk that. I know it’s a different bike but look at the 1290 Superduke Akrapovic v the stock exhaust, doesn’t make sense does it ?
 

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If a bike comes lean from the factory (which most do these days), some of the very loud shorty's have been known to create dips in the powerband or cause existing dips to get worse due to lean conditions from the lack of back pressure. You can fix that with a fueling module but that's getting tougher to do with all the Euro5 crap. My 890R came with a dip in the torque curve at 4800 and when I threw on an Akra slip-on it got worse. Luckily I was able get a Coober and that made the bike run a little better. It's still the smoothest using the "Street" fuel map. Sport and Track make it snatchy.
 

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Luckily I was able get a Coober and that made the bike run a little better. It's still the smoothest using the "Street" fuel map. Sport and Track make it snatchy.
Which Coober? - OLD or NEW? - I have the OLD one on my 790 and it runs spot on in SPORT. I don't bother with TRACK.
ime SPORT and TRACK are VERY direct and you may wish to look at eliminating throttle backlash at the grip (the plastic spacer thing). "Feathering" ride by wire throttles is a skill to be learned imo. One day ;)
 

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Which Coober? - OLD or NEW? - I have the OLD one on my 790 and it runs spot on in SPORT. I don't bother with TRACK.
ime SPORT and TRACK are VERY direct and you may wish to look at eliminating throttle backlash at the grip (the plastic spacer thing). "Feathering" ride by wire throttles is a skill to be learned imo. One day ;)
I have the new one. It's not as nice as I'd like it to be (I'm picky) but it's not bad at all.
 

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If a bike comes lean from the factory (which most do these days), some of the very loud shorty's have been known to create dips in the powerband or cause existing dips to get worse due to lean conditions from the lack of back pressure. You can fix that with a fueling module but that's getting tougher to do with all the Euro5 crap. My 890R came with a dip in the torque curve at 4800 and when I threw on an Akra slip-on it got worse. Luckily I was able get a Coober and that made the bike run a little better. It's still the smoothest using the "Street" fuel map. Sport and Track make it snatchy.
I thought the riding modes only changed the throttle response, they actually also change the fueling? Does this show on dyno?
 

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I still rock the stock standard exhaust , I did on my 790 DUKE as well, I didn’t see the need to spend money on something that already works and sounds great. ;) I have a few Engine Sound videos up on my YouTube and you can hear how good it sounds.
 

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I thought the riding modes only changed the throttle response, they actually also change the fueling? Does this show on dyno?
That is a good question, I assumed the riding modes changed the fuel mappings. I always keep my bike in Track mode and change the throttle maps in the Track mode settings. When I hit reserve using the Track throttle map, switching to the Street throttle map gets me two bars and increases my range.
 

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switching to the Street throttle map gets me two bars and increases my range.
Interesting.

Regarding the "modes" - I do not know how KTM does this but I know of ride by wire systems that have NON-LINEAR throttle mapping.

It's also common for closed loop systems to be MAP based fueling and TPS for open loop. Again I don't know how KTM does it. The early COOBER 100% references the THROTTLE POSITION (I think the feed twixt throttle body and ECU)
 

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you should be able to remove the carbon cover at the end and drill the rivets holding it in place? Although I thought that the US version had a removable baffle?
What I meant by "easily" is removing one little bolt and pulling it out like on my Kawasaki. Euro5 crap is a lot harder to mess with. I havent gotten the desire to drill rivets and all the other crap I've seen folks have to go through. Maybe I will down the road.
 

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I'm slowly talking myself into a SC Project S1. A few questions for the experts here:
  • I do a fair bit of riding with a pillion. Does the SC Project S1 actually work w a pillion - I've heard of heat issues with some of the shorter pipes?
  • I'm in this mostly for the sound, but I'll pass if that will come at the cost of HP. Is there a definitive story on what mufflers will/won't reduce HP? I'm not interested in de-catting or removing the DB-killer... I don't need volume, just a lil growl.
  • Anybody looking to unload an S1 in great condition? I might be in the market.
 

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I'm slowly talking myself into a SC Project S1. A few questions for the experts here:
  • I do a fair bit of riding with a pillion. Does the SC Project S1 actually work w a pillion - I've heard of heat issues with some of the shorter pipes?
  • I'm in this mostly for the sound, but I'll pass if that will come at the cost of HP. Is there a definitive story on what mufflers will/won't reduce HP? I'm not interested in de-catting or removing the DB-killer... I don't need volume, just a lil growl.
  • Anybody looking to unload an S1 in great condition? I might be in the market.
I have the SC Project and love it. I think looks wise, it is the right size for the bike. Sounds amazing too. I don't ride with a pillon and have removed all of that hardware to save weight.
 

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Has anyone any idea if the 790 akra slip-on is the same as the 890? Part number is different.. due to homologation I guess. I found a good deal on a 790 one.
I think the difference on most that differentiate between 790/890, is that the internals are not removable on 890 units for Euro5 compliance.
 

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Hi! I’m new here.. I have a 2021 890 R in the USA with the full Akra Evo system and can confirm that the db killer is in fact removable via 1 small machine screw.. There is a removable rubber plug on the inboard side of the carbon fiber end cap. Simply pull on plug to remove it and that exposes the hole that you insert your socket wrench into to loosen and remove the machine screw. Once screw is removed, grab the end of the insert with a pair of pliers of your choice and give it a good yank… There you have it. That’s my experience as of a few weeks ago…
 
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