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Discussion Starter #1
Anyone been running a slip on without a tune?
Im fairly happy with the stock tune and the bottom end twitchiness isnt a problem for me, but I would like some more noise for when Im wearing earplugs.

Just how lean are these bikes running? Is it safe to have a slip on with the stock fuelling?
 

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If you look at the stock pipe "Slip On" - you'll see it has no dB killer - it's just a packed expansion chamber. Straight through - no baffle inside. And the simple fact is that pretty much any E-marked slip-on will have little effect on the performance. In fact some are known to make it worse. Esp the short and thus loud ones. Whether you want loud rather than go - or just different looks - well that's a personal thing.

A Cat-delete is a whole different matter. This is the primary point of scavenge tuning and is what affects how much and when the pressure pulses are reflected back towards the valves. Mess that up and yes the KTM runs VERY lean. Valve burning lean.

I'd rather sort the fueling than make it loud - just my 0.02
 

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Discussion Starter #3
I think KTM did a good job with both the sound and looks of the stock pipe. I haven't ridden the bike with earplugs yet, but if I can hear what the bike is doing, might be leaving it stock until I'm prepared to get fuelling sorted.
 

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No need for the tuning. Since the catalytic converter is in a separate box under the frame, you're only changing the muffler so there's not much difference except a little more sound.
 

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If you look at the stock pipe "Slip On" - you'll see it has no dB killer - it's just a packed expansion chamber. Straight through - no baffle inside. And the simple fact is that pretty much any E-marked slip-on will have little effect on the performance. In fact some are known to make it worse. Esp the short and thus loud ones. Whether you want loud rather than go - or just different looks - well that's a personal thing.

A Cat-delete is a whole different matter. This is the primary point of scavenge tuning and is what affects how much and when the pressure pulses are reflected back towards the valves. Mess that up and yes the KTM runs VERY lean. Valve burning lean.

I'd rather sort the fueling than make it loud - just my 0.02
Damm i removed my cat and did not think i would need to retune been riding it like that for about a month you think they can flash the ecu or i need a power commander or something simmilar? Also just bought an sc project slip on they recomended i get a rapid bike auto tuner because i removed the cat also have any of you guys ever heard of this tuner how good is it?
 

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Anyone been running a slip on without a tune?
I've been running the Arrow with the dB killer removed and stock map. I did not find the combination to be too lean. Fueling was crisp, with some mild popping on the overrun. Still strong in the mid-range with no hesitation.

I had planned to do the cat-delete and while It's at the dealer for the first service, I asked to load the Akra map. The mid-pipe was on back order, but should be here Friday.

I'll end up with some miles this weekend with the stock cat and Akra map, so we'll see how that goes.

5385
 

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Damm i removed my cat and did not think i would need to retune been riding it like that for about a month you think they can flash the ecu or i need a power commander or something simmilar? Also just bought an sc project slip on they recomended i get a rapid bike auto tuner because i removed the cat also have any of you guys ever heard of this tuner how good is it?
There are places that say they can FLASH the ECU. There is a PC5 solution (with a tiny caveat - a warning light on the dash stays on). Rapid Bike - I've not read anything about their top end devices. KTM do have a CAT DELETE map. But say it is a race only map - designed specifically to suit their AKRA. Austin Racing have/had a Cat delete ATOM but pretty much say "At your own risk". I have direct experience of none.

As EU regs strengthen - slip-ons will become more a Styling statement. EU3 permitted removable baffles. EU4 really does not but dealers were permitted to sell off existing stock. EU5 and they have to make baffle removal difficult or close to impossible.

I bought my Wings because I got a good deal on it with the COOBER box. But I have just stuffed the dB killer back in - mainly because it has a Spark Arrester (which the OEN does not) and rural fires are a major issue here at the moment - but also because I have become rather bored with the noise ( The Wings with DB killer in is actually quieter than the OEM)

The LC8c engine "reputedly" was designed from the get-go with a Cat-Box as part of the engine management - and - reading between the lines a bit - runs the ECU lean and uses the lambdas to enrich to hit AFR values. Most ECUS are set to more or less correct (STP) and the ECU makes minor changes.

I have NOT - personally - seen any evidence to suggest a cat delete improves the bike either. I don't say it doesn't - I simply do not know.

If it were me - I'd put the cat back on. But I use my bike exclusively on the road and there's pretty much always traffic about too.
 
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