Removing the catalytic convertor, worth it?

Noobie

Noobie

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Just a general question really. If you remove the standard end can, I believe most just slip on with little or no changes bike wise??

If however after reading up on de-catting a bike I've seen many comments on O2 delete, healtech to trick the flappy thing, power commander this, flash the ecu that and it all becomes very confusing.

So, have you ever exchanged the exhaust, just the can or more and what did you have to do to get the improvements you were after and lastly was the amount spent worth it?
 
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Now tha knows, not proper yorkshire till tea is bashed against te bike for her to sail. None of that southern poofta prosecco

I remember on my second blackbird (carby model and pre cat) I fitted a full akropovic exhaust system. They also fitted a K&N filter, a stage 1 dynojet kit and all set up properly on a rolling road. It was not cheap. I did get a nice clean crisp sound, 150bhp at the wheel but in real term road use, the spend was more because I wanted to do it rather than I needed to do it.

On the k7 gixxa 750, I was tempted to remove the factory exhaust/combined cat but then loads of things were popping up such as mentioned, a de cat exhaust, then an O2 delete, then removing the servo/servo plate, install a heal tech, installing a power commander and then getting everything set up properly. That's before you even deal with fault codes due to the changes. At the time it seemed a stupid amount of work and cash for a 10-15bhp gain so opted for one tooth less on the front cog for better day to day use.
 
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I wouldn't just change the can on a catted exhaust. Especially on big twins and even more especially if the cats are in the cans. I've done it a couple of times and it's never been right without a remap. And if you're going to pay for that you might as well fit a full decat system and get the maximum benefit. Which isn't just performance. Decatting sheds a load of weight and greatly reduces radiating heat. But you must remap. A custom map to correct fuelling and ignition hampered by emmissions regs can greatly increase the rideability of the bike. Don't think purely in terms of headline figures. A sweet throttle connection and filling out the holes and flats in the power and torque curves can transform the way a bike feels to ride.

As to the O2 sensor question, just ask your dyno tuner. If you need blanking plugs you can get them from sites like Wemoto. Any tuner who's mapped the model of bike in question before will know what needs deleting within the ECU, what needs plug-in work-arounds etc.

Avoid PCs if possible. And downloaded generic maps. A custom remap is much better as no two bikes are exactly the same. And it's cheaper.
 
Blackbird was a 2001 Fi, left pretty much standard, as that was my go to bike for two up with madam Bounder.
K4 gixer thou, Yoshi tri oval, bespoke map, ECU update so no speed limit in 6th, nothing outrageous, saw it read 186 on the speedo and was still going.
 
I’ve got a Healtech, but having seen videos on fitting it, I’m not going to bother. @Swiss T said it’s made a big improvement on his Speed Triple though, so if I get a boost of confidence I might give it a go.

I’ve had cans on other bikes - put an Akra on my S1000RR and it was a waste of money. Barely any difference in sound and less tractable low down. I switched back to the hideous OEM.
Which confirms what Gimlet said…needs a remap.

That said, Skitzy’s SDR sounds awesome and he says there’s no down sides to it, so these things must be bike dependent.
 
Dox said:
I’ve got a Healtech, but having seen videos on fitting it, I’m not going to bother. @Swiss T said it’s made a big improvement on his Speed Triple though, so if I get a boost of confidence I might give it a go.

I’ve had cans on other bikes - put an Akra on my S1000RR and it was a waste of money. Barely any difference in sound and less tractable low down. I switched back to the hideous OEM.
Which confirms what Gimlet said…needs a remap.

That said, Skitzy’s SDR sounds awesome and he says there’s no down sides to it, so these things must be bike dependent.
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Its just a bit fiddly; you got this.
You may even be able to disable it in place with tuneecu.
 
Dox said:
Now you’ve got me googling tuneecu 🙏
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I’ve used it in the past for my Thruxton & 1198; I think it was free then. Its advanced a bit now & you need to pay; its about €25 for 12-months which allows you to connect to 5-bikes. I’m just getting used to it again & will be using it to bleed the Speedie abs system. You could definitely disable the flapper on the 1198, but I haven’t had chance to check if you can on the Speedie. I think tuneecu comes in two flavours; windows & android.
 
I read a lot of forums just bevause I'm interested. On the KTM one I noticed on the superduke R it was often the case that if you were not pennies short, a full akro system may have been used and others had a mid pipe/can change. Then came the sas delete, then came the O2 delete (both with dongles to stop error codes and quite cheap) and the I remember seeing something about a cannister removal??? What was said was if you do the sas and or O2 delete, it would destroy your cat in some way. What you you done to your's @The skitz
 
Noobie said:
I read a lot of forums just bevause I'm interested. On the KTM one I noticed on the superduke R it was often the case that if you were not pennies short, a full akro system may have been used and others had a mid pipe/can change. Then came the sas delete, then came the O2 delete (both with dongles to stop error codes and quite cheap) and the I remember seeing something about a cannister removal??? What was said was if you do the sas and or O2 delete, it would destroy your cat in some way. What you you done to your's @The skitz
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I left the cat in place .. At the time it was only the akra that was official to ktm so no cat no warranty.. My bike is loud loud so I could only imagine it de catted?
 
Hugo Magnus said:
I was advised against with the Multi as it is just too noisy (whatever that is) I would like to hear one that has been done so I can hear it for myself.
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My multi has been done, sounds good but not too noisy and it runs really nicely. I believe it had the necessary tweaking done at the same time. My S2R in my avatar has also been done, initially just the end can but now the whole system, it sounds positively orgasmic imo although a little lumpier at low rpm now.
 
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Hugo Magnus said:
I was advised against with the Multi as it is just too noisy (whatever that is) I would like to hear one that has been done so I can hear it for myself.
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I did a MTS1200 2012 model, new air in-take, filter, de-cat, de-flapped, new Ecu*.. ++150bhp and the back wheel and electric feeling torque... quite scary at first.... sadly the bike is no more, as per my brothers left leg.

That engine has a fuel and spark Map for each gear and cylinder... no wonder it runs like shite when the gear indicator goes wrong.

I was told the twin spark wasn't mappable. After that I've no idea.


Biggest improvement "bang for buck" was the de-flapper.
 
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AirCon said:
I did a MTS1200 2012 model, new air in-take, filter, de-cat, de-flapped, new Ecu*.. ++150bhp and the back wheel and electric feeling torque... quite scary at first.... sadly the bike is no more, as per my brothers left leg.

That engine has a fuel and spark Map for each gear and cylinder... no wonder it runs like shite when the gear indicator goes wrong.

I was told the twin spark wasn't mappable. After that I've no idea.


Biggest improvement "bang for buck" was the de-flapper.
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My 2010 mutley, k&n, butterfly drilled out, decat but way too loud for touring, so back in, plenty fast as an adventure bike would hit the rev limiter in 5th!
My 2017 dvt, Termi and up-map, EVE, left the cat in again, too loud for touring again.
As Paul said the best bang for buck these days are the exhaust valve eliminators, either buy one or do as I did and drilled the feckers out for free!
 
AirCon said:
I did a MTS1200 2012 model, new air in-take, filter, de-cat, de-flapped, new Ecu*.. ++150bhp and the back wheel and electric feeling torque... quite scary at first.... sadly the bike is no more, as per my brothers left leg.

That engine has a fuel and spark Map for each gear and cylinder... no wonder it runs like shite when the gear indicator goes wrong.

I was told the twin spark wasn't mappable. After that I've no idea.


Biggest improvement "bang for buck" was the de-flapper.
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Thank you I appreciate all the good bits, but was it too noisy?
 
Noobie said:
I read a lot of forums just bevause I'm interested. On the KTM one I noticed on the superduke R it was often the case that if you were not pennies short, a full akro system may have been used and others had a mid pipe/can change. Then came the sas delete, then came the O2 delete (both with dongles to stop error codes and quite cheap) and the I remember seeing something about a cannister removal??? What was said was if you do the sas and or O2 delete, it would destroy your cat in some way. What you you done to your's @The skitz
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I did all that with my gen 1 SDR. Bought the full Akra system which came with SAS blanking kit and a factory map to adjust the fueling. The Gen 1 had no charcoal cannister, that came in with the gen 2. At the time (2016) the Akra was about £1800 if I remember correctly. I got a deal on it from the dealer I bought the bike from. It was worth spending the money to buy an exhaust that had been properly developed for that bike. It was loud but not offensive. In fact they really got it spot-on. It sounded gorgeous and it made a big difference to performance. Other owners I knew had fitted cheaper non-approved systems and they were always horrible loud. The problem now is that approved de-cat exhaust systems have become obscenely expensive, especially on Ducatis, (7 grand for a V4 Panigale - really??) and people are looking for cheaper ways to unlock the performance, improve the sound and ditch all the Euro 4/5/6 (anyone counting?) emmissions crap. When you start doing this you really have to do your homework and look at the whole job holistically.

I later fitted a DNA pancake airbox bought from P3 Tuning and that came with a pre-programmed PC4 which I fitted myself. It was good but a custom map would have been better as the gen 1 SDRs had a horrible graduated throttle ramp that left the twist grip feeling very disconnected from the back tyre. A custom map would have corrected this. With the Gen 3 KTM finally addressed the throttle connection.
I had planned a custom remap but I ended up selling the SDR and buying a Harley... And don't start me on Harley exhaust/cam/induction tuning. That really is a rabbit hole. You'd think it would be simple on those big, basic chugging pushrod engines, but it's anything but. It's an absolute minefield of options and you can get it spectacularly right or spectacularly wrong.
It took me a year to figure out the best way to go and then I sold it enyway and bought a Rocket 3. And now I'm back there again with that bike... It needs uncorking as the exhaust system is very restrictive, but options are limited.
 
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BobTheBounder said:
My 2010 mutley, k&n, butterfly drilled out, decat but way too loud for touring, so back in, plenty fast as an adventure bike would hit the rev limiter in 5th!
My 2017 dvt, Termi and up-map, EVE, left the cat in again, too loud for touring again.
As Paul said the best bang for buck these days are the exhaust valve eliminators, either buy one or do as I did and drilled the feckers out for free!
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I did the full uncorking job on my old KTM 990 SMT. Leo Vinci straight-through cans (the cats were in the cans back then) DNA airbox with extended intakes, SAS removal and crank case breather adaption, then a custom map at BSD Performance. It was spectacularly good when I'd got it all done, but like your Multi, it was too loud for touring. But it wasn't the exhaust that offended, it was the induction roar from the pancake airbox.
On short rides ragging it round B roads it was a riot, like riding a giant motocrosser, but on long rides it became very wearing. Not only the noise but the way it made the bike begged to be thrashed all the time, which isn't what you want for distance riding. It's put me off doing it to my 1190, as I do tour on that. I will do it eventually because the DNA box I fitted to my Superduke wasn't too bad, and the 1190 engine is very similar. But open air boxes made the 990's really raspy.
 
Power Commanders are a (not that) cheap & nasty way to ‘tune’ a bike. They just spoof the ECU into thinking the air is colder than it is, so the ECU doses more fuel at every stage of its map which overcomes the leanness of modern Euro 4/5/5+ engines.

The reason Ducati exhaust upgrades are so expensive is they come with a map that not only alters the fuelling maps but also retunes the BBS so the riding aids and their interaction with the ECU is also altered. Mind you you’d really only get the benefit of that on a track. Third party tuners can’t access the BBS and its rider aid algorithms. Ducati know this so they milk the prices for maximum benefit to them obviously.
 
West Cork Paul said:
Power Commanders are a (not that) cheap & nasty way to ‘tune’ a bike. They just spoof the ECU into thinking the air is colder than it is, so the ECU doses more fuel at every stage of its map which overcomes the leanness of modern Euro 4/5/5+ engines.

The reason Ducati exhaust upgrades are so expensive is they come with a map that not only alters the fuelling maps but also retunes the BBS so the riding aids and their interaction with the ECU is also altered. Mind you you’d really only get the benefit of that on a track. Third party tuners can’t access the BBS and its rider aid algorithms. Ducati know this so they milk the prices for maximum benefit to them obviously.
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I'm so glad my Streetfighter is analogue. Ducati are really pulling buyer's pants down with all this electrickery. KTM aren't far behind them.
 
West Cork Paul said:
Power Commanders are a (not that) cheap & nasty way to ‘tune’ a bike. They just spoof the ECU into thinking the air is colder than it is, so the ECU doses more fuel at every stage of its map which overcomes the leanness of modern Euro 4/5/5+ engines.

The reason Ducati exhaust upgrades are so expensive is they come with a map that not only alters the fuelling maps but also retunes the BBS so the riding aids and their interaction with the ECU is also altered. Mind you you’d really only get the benefit of that on a track. Third party tuners can’t access the BBS and its rider aid algorithms. Ducati know this so they milk the prices for maximum benefit to them obviously.
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Completely agree. There is no substitute for a full custom remap. Where possible...
 
Gimlet said:
I'm so glad my Streetfighter is analogue. Ducati are really pulling buyer's pants down with all this electrickery. KTM aren't far behind them.
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Whilst I don’t doubt for one moment Ducati (and others eg BMW, KTM) are using the situation to their advantage, it is all driven by having to comply to EU (and Californian) emissions regs. The easiest way to do that is to map the engine so it can pass the emissions & noise regs which are measured at certain revs/speed drive by.
 
West Cork Paul said:
Whilst I don’t doubt for one moment Ducati (and others eg BMW, KTM) are using the situation to their advantage, it is all driven by having to comply to EU (and Californian) emissions regs. The easiest way to do that is to map the engine so it can pass the emissions & noise regs which are measured at certain revs/speed drive by.
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True. But many of these regulations come in because the big manufactures have lobbied the EU Commission for them, because compliance makes life harder for smaller and non-EU competitors and it forces buyers to purchase own-brand approved accessories rather than independent after-market products.

And it's not just the auto industry, nor just at EU level. It's been going on in the UK construction industry for years. A big corporate manufacturer invents some product, convinces government that it's vital for safety or eco efficiency and suddenly it's use becomes compulsory in building regulations and the manufacturer makes a fortune.
Sometimes the results are disastrous, eg. Grenfell Tower.
 
Mot passing is also a consideration. I know when checking a bikes mot history a lot mention noisey exhaust but as a mention and not a fail
 
Noobie said:
Mot passing is also a consideration. I know when checking a bikes mot history a lot mention noisey exhaust but as a mention and not a fail
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There is no measurement system for testers to check any compliance (which does not exist anyway for the mot test) even the police can't enforce loud exhausts, the best they can do is hand out an arbitrary £100 fine to boy racers (who won't argue the validity) if they get residents complaints.

I had a stupid neighbour with a 'Gary boy' straight pipe fiesta (she was my age ffs) neither council or police were interested saying it was each others responsibility 🙄
 
There must be some sort of noise limit for the fines imposed by noise cameras to be enforced.

A lot of it isn't the volume of sound produced but the way the bike is being ridden. You can ride a loud bike with due consideration and very few if any people are offended by it. Or you can ride a a less noisy bike like a twat and attract a lot of very black looks, even if you're not breaking the speed limit.

My Steetfighter is very loud (and it'll get louder when I put the full Termi race system on it..) so I try not to piss people off. I ride through town in a highish gear on a light throttle and lots of people look round at that rumbling noise, some taking a close look at the bike to see what it is. But I've never seen any hostility on anyone's face. Most seem to think it's cool. If I was in 1st gear and blipping the throttle needlessly I imagine expressions would change markedly.
I don't race up and down the same piece of road on a Sunday near people's houses (time and place and all that) and I try to avoid returning home on it late at night and disturbing my neighbours. Unfortunately many riders don't bother to consider other people and so ruin things for the rest of us.
 
The skitz said:
I left the cat in place .. At the time it was only the akra that was official to ktm so no cat no warranty.. My bike is loud loud so I could only imagine it de catted?
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Which of course raises another consideration. Dealers/companies sometimes have a bad rep for refusing warranty work so best check if mods during the warranty period, are ok or will cancel your warranty claim. My own feeling is Skitz approach of play smart during the warranty period with officially approved changes, after that there are choices
 
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