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Yes, 2" up to the "Y". Heres pics of it with the fairings on. Most race fairings don't cover the front like that but the Catalyst Racing Composites fairings do and theres only a couple of mm clearance now. I might have to put some floor and tunnel shielding there.
I once installed a bigger diameter header which had an inch clearance to the fairing but the heat warped the plastic.
 

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Have you actually ridden the bike yet with this new Cat-less IXIL header pipe installed, and did it FEEL more powerful or responsive in any way ? Incidentally 91 octane fuel is pretty ****. in NZ 91 is considered standard grade, and 95 is considered premium. In some gas stations you can get 97.5 or even 98 'high' octane fuel. Personally I always run all my bikes on the 95, and it's recommended to run all Turbocharged cars on the 95 as well. Interestingly in the UK where I originally come from 95 octane is standard and 97 or 98 octane is premium, with 99 octane being considered 'high'. Here in NZ my shop uses a dyno tuning company who will only tune high end race bikes to run on BP Ultimate 98, and then tell you to not run them on anything else. But were talking 210/215 bhp Fireblade superbikes here, not weasly 53 horsepower learner legal machine. I guess if you can easily get 95 octane, then tune it for that and run it on that, I would
 

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Discussion Starter · #23 ·
@Ecgpeow I'm personally a little sceptical of the M16-039-004 map that you've loaded, as it leans things out quite a bit. I think until you get the custom tune, the Yoshi one M16-039-005 would be a safer one.


Yeah, that would explain why it wasn't popping any more. With the PCV installed I'm using the -504 map. I'd say it pulls maybe a little stronger but it's too subtle to really matter. My goal in all of this is to get a few more mph at the end of the straights on track, so that's where I'll be looking for a difference. I know the rider is the biggest factor but we all want to stack the odds in our favor, amiright!
 

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I've had my cat delete done for a while now, you'll definitely notice more low down pull; like it'll pull from 2500 as easily as it used to at 3000 before the mod.
You'll absolutely need to adjust the fuel map for this mod.

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Quite frankly, I wouldn't really notice if the bike pulls a bit better at 2,500 rpm.
What about the intake? Any mods there?
A bigger chimney won't make the fire burn hotter if the door of the stove stays the same size. :)
 
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Quite frankly, I wouldn't really notice if the bike pulls a bit better at 2,500 rpm.
What about the intake? Any mods there?
A bigger chimney won't make the fire burn hotter if the door of the stove stays the same size. :)
In commutting duties it's a bit more chillaxed riding because of it. It's more so freeing up restriction then making it bigger. But yes, more recently I've modified the throttle bodies; and next month will be getting larger headers and tidying up the head ports to release a couple more ponies :)

what can i say, I'm a single man, so have time and money to burn ;)
 

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I did a leak test on my poor man's decat the other day and the welding from the zost shop isn't up to spec. I see this IXIL one is also a wider diameter for better flow so I just put an order in for this thing too. Will revert back once installed.
@Ecgpeow what did you do about it not having the tabs to mount the heat shield; I'm thinking of taking it down to another exhaust shop (the other mob closed down) and get them to weld on something for me. But what did you do?
 

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I've read that removing the cat doesn't really do much on modern vehicles. All of them have been engineered with the cat in mind so removing it won't change much performance wise. Do you notice any gains from it?
 

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@500rider86 I'd call total BS on anyone who says placing a restriction has nil effect on output. Increase flow = increased power
BUT, with modern EFI engines the vehicle is electronically tuned to a lower state of performance due to the higher back pressure from the restrictions in the exhaust of both the cat & muffler. Remove or replace with less restrictive, one or both of these and flow increases; that is, the gasses exit the combustion chamber more effectively, meaning more space for clean air and fuel to enter. This however, can mean that without increasing the fuel amount to match the greater clean air volume entering the combustion chamber, that the engine will run leaner. This leaner situation can potentially have a bad effect on an engine. Most engines with sensors can account for the change and adjust their fuel map accordingly, others might need some manipulation.
Answer to your question of any gains noticed... yes, actually mentioned a few post above, pulls from further down in the rev range. Feels like it picks up faster too, but where talking small power gains here, so the butt dyno isn't going to be super accurate.
 

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I got my IXIL headers, I'm generally happy with everything except the outer diameter of the link pipe is ridiculously large, I'm trying to get in contact with them about support, since evidently the outer diameter is too large (inner diameter of link pipe is ~42mm, outer diameter of IXIL headers is ~48, inner diameter is ~44mm). No sure how that could possibly fit stock or aftermarket link pipes...

Here's an image of the issue. Link pipe actually fits INTO the headers. Impossible to tighten down or seal...
 

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A few years back I had the cat on my 2005 BMW R1200ST opened up and removed all the internals, then welded back.
I actually lost torque in the mid range where I needed it most.
Before, in top gear roll on, I could pull away substantially from my brothers R1200RT, but after gutting the cat, I could not.
I wound up replacing it with a stock header set I got off eBay.
I was always thinking that more open and free flowing was better. But after that episode, I have more confidence in the engineers that design them.
 

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I got my IXIL headers, I'm generally happy with everything except the outer diameter of the link pipe is ridiculously large, I'm trying to get in contact with them about support, since evidently the outer diameter is too large (inner diameter of link pipe is ~42mm, outer diameter of IXIL headers is ~48, inner diameter is ~44mm). No sure how that could possibly fit stock or aftermarket link pipes...

Here's an image of the issue. Link pipe actually fits INTO the headers. Impossible to tighten down or seal...
What I did was get the Dremel out with cut off wheel and slice two cuts into the link pipe 90 degrees offset from the cuts in the slip-on, so it would compress with clamping. I had to source a clamp big enough for the OD of the ixil, ended up with a car muffler clamp. Sealed it up with some RTV silicone, and no more problem :)
 

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What I did was get the Dremel out with cut off wheel and slice two cuts into the link pipe 90 degrees offset from the cuts in the slip-on, so it would compress with clamping. I had to source a clamp big enough for the OD of the ixil, ended up with a car muffler clamp. Sealed it up with some RTV silicone, and no more problem :)
Yeah this is what I ended up having to do, since IXIL said that was how it was supposed to be. Used a dremel to cut 4 indents of about 2cm (about the width of the clamp), got some higher temp copper silicone sealant, put a nice bead on, squeezed the clamp until sealant was getting pushed out of all the angles. Looks like it works for now, but **** does it look messy.
 

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A few years back I had the cat on my 2005 BMW R1200ST opened up and removed all the internals, then welded back.
I actually lost torque in the mid range where I needed it most.
Before, in top gear roll on, I could pull away substantially from my brothers R1200RT, but after gutting the cat, I could not.
I wound up replacing it with a stock header set I got off eBay.
I was always thinking that more open and free flowing was better. But after that episode, I have more confidence in the engineers that design them.

Similar to why wide open drag pipes usually reduce low and mid range performance.
Yes - you'll gain a little on the top end by having no restriction, but that's not where most usual riding is done.
 

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@500rider86 I'd call total BS on anyone who says placing a restriction has nil effect on output. Increase flow = increased power
BUT, with modern EFI engines the vehicle is electronically tuned to a lower state of performance due to the higher back pressure from the restrictions in the exhaust of both the cat & muffler. Remove or replace with less restrictive, one or both of these and flow increases; that is, the gasses exit the combustion chamber more effectively, meaning more space for clean air and fuel to enter. This however, can mean that without increasing the fuel amount to match the greater clean air volume entering the combustion chamber, that the engine will run leaner. This leaner situation can potentially have a bad effect on an engine. Most engines with sensors can account for the change and adjust their fuel map accordingly, others might need some manipulation.
Answer to your question of any gains noticed... yes, actually mentioned a few post above, pulls from further down in the rev range. Feels like it picks up faster too, but where talking small power gains here, so the butt dyno isn't going to be super accurate.
You guys are doing some good work here...but....tuning these EFI bikes about like herding cats and pulling teeth. They engineered these engines these days as you say for the way they set them up. I've always suspected this bike was seriously de-tuned to meet that below 50 hp mark for that euro requirement. So who knows what you can get out of this engine. Problem is many things must match. Bitch getting there. I think the hp could be doubled out of this motor with the correct set up. That would require a cam change, (more lift longer duration) and maybe a piston change to raise the compression levels.
 

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I got my IXIL headers, I'm generally happy with everything except the outer diameter of the link pipe is ridiculously large, I'm trying to get in contact with them about support, since evidently the outer diameter is too large (inner diameter of link pipe is ~42mm, outer diameter of IXIL headers is ~48, inner diameter is ~44mm). No sure how that could possibly fit stock or aftermarket link pipes...

Here's an image of the issue. Link pipe actually fits INTO the headers. Impossible to tighten down or seal...
Is there any videos of the sound and what steps exactly needs to be done to have no computer problems etc
Do you have any videos please?? Can u send it to [email protected]
 

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Hi I’m new to this forum and also ride a 2021 CBR 500, I was wondering if I could go catless on mine but wanted to know if I had to do something else to keep my engine light off as well. Any help would be appreciated.
 
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