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I've had Delkivic pipes in the past and was extremely impressed with the quality and sound. So I was looking to order one for the Vee. I saw a regular slip on and a de-cat slip on. Anyone here tried a de-cat exhuast? Delkvic or Arrow makes one I believe? What are the benefits or down sides to leaving the cat or removing it. I live in NC so emissions isn't a problem here.

Thanks Austin
 

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"live in NC so emissions isn't a problem here."

In the grand scheme of things what exhausts in Tenn doesn't necessarily stay in Tenn. That's why they design cats.
Either that or we are all being lied to by pseudo science.
 

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I've had Delkivic pipes in the past and was extremely impressed with the quality and sound. So I was looking to order one for the Vee. I saw a regular slip on and a de-cat slip on. Anyone here tried a de-cat exhuast? Delkvic or Arrow makes one I believe? What are the benefits or down sides to leaving the cat or removing it. I live in NC so emissions isn't a problem here.

Thanks Austin
Remove the catalytic converter and don't you need a plug-in chip to convince the ECM the cat is still there?

Whatever you decide, I will be very interested in the outcome. Being a recent model owner myself.
 

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Unless your bike has an 02 sensor after the cat, there ECU can't know whether or not you have a converter. The pre-cat 02's function is as an input to the ECU to adjust air/fuel ratio via injection duration, the rear 02's function is to monitor the efficiency of the catalytic converter.
If both 02 sensors have the same readings at the same time when hot, the ECU judges that wahat's between the sensors, the cat, is below the ECU's threshold of efficiency and will turn on the malfuction indicator lamp and set a cat efficiency code.
No rear 02, no efficiency code , no malfunction lamp on for a cat reason.
 

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Sorry I hate long posts but this will be one and I'm not sure it is relevant to a bike.

A relative inherited a car from his mother, she owned it from new and it was serviced it's entire life by the same mechanic.

The new owner drove the car from Melbourne to Sydney a trip of 900ks, on the highway the car was perfect but when he reached city traffic the engine temperature climbed, it did not overheat, it just got hot.

He asked me to look it over, I found everything as it should be and working well, I installed a over ride switch so he could turn the thermo fan on if he needed to on his trip back.

On the trip home it did the same thing, it ran fine on the highway but the temperature climbed when the car slowed down.

He took the car to it's life long mechanic and they determined it needed a motor rebuild, I called BULL SHIT but he had the motor rebuilt anyway.

After the rebuild the problem persisted, the mechanics were stumped and could give no reason for the problem but did not find a problem with the motor when it was stripped either "which they did not tell my mate".

The car sprung a exhaust leak so he took it to the local exhaust specialist, when they removed the exhaust they found the cat had been gutted, it was still there but it had no internal parts.

When they rang to tell him he needed a new cat he asked why, they told him while he was moving at speed it would be fine but when he slowed heat from the exhaust would transfer back up the exhaust and into the motor.

This explained his symptoms exactly, he had the new cat fitted and his over heating problems went away.

He returned to the original mechanic to get back the money he paid on the rebuild as they were the ones that gutted the cat in the first place, they had done it about 4 years earlier to save the old girl some cash.

After I was told this I started to investigate and found heaps of storeys where people had unexplained temperature rises after stuffing with their cats.
 

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Sorry I hate long posts but this will be one and I'm not sure it is relevant to a bike.



A relative inherited a car from his mother, she owned it from new and it was serviced it's entire life by the same mechanic.



The new owner drove the car from Melbourne to Sydney a trip of 900ks, on the highway the car was perfect but when he reached city traffic the engine temperature climbed, it did not overheat, it just got hot.



He asked me to look it over, I found everything as it should be and working well, I installed a over ride switch so he could turn the thermo fan on if he needed to on his trip back.



On the trip home it did the same thing, it ran fine on the highway but the temperature climbed when the car slowed down.



He took the car to it's life long mechanic and they determined it needed a motor rebuild, I called BULL SHIT but he had the motor rebuilt anyway.



After the rebuild the problem persisted, the mechanics were stumped and could give no reason for the problem but did not find a problem with the motor when it was stripped either "which they did not tell my mate".



The car sprung a exhaust leak so he took it to the local exhaust specialist, when they removed the exhaust they found the cat had been gutted, it was still there but it had no internal parts.



When they rang to tell him he needed a new cat he asked why, they told him while he was moving at speed it would be fine but when he slowed heat from the exhaust would transfer back up the exhaust and into the motor.



This explained his symptoms exactly, he had the new cat fitted and his over heating problems went away.



He returned to the original mechanic to get back the money he paid on the rebuild as they were the ones that gutted the cat in the first place, they had done it about 4 years earlier to save the old girl some cash.



After I was told this I started to investigate and found heaps of storeys where people had unexplained temperature rises after stuffing with their cats.


This does not sound plausible. The cat is what gets hot. How does an engine get hot with less exhaust restriction?


Sent from my iPhone using Tapatalk
 

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That was my belief to but the experts proved me wrong.

A blocked cat would have caused a problem during the 900k trip at 110kph restricting the exhausts escape not when it slowed.

He was given the old cat to take back to the original mechanic to help with the refund.
 

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Rolex, there is an explanation why a gutted cat can cause an engine temperature to rise.
Years ago when cat converters were mandated in the US(1975), a few companies began selling... a "Catalytic Converter Test Pipe", which was nothing more than a straight section of exhaust tubing with flanges to replace the cat converter. "Not For On-Road Use" was the usual sticker on the box. I used one my self for one week after my 1979 Ford Mustang 2.3L Turbo ate it's turbocharger while on vacation. My converter was oil-soaked, so I had it sitting in a large bucket of solvent for a week while I waited for a new turbocharger to arrive.
On my Mustang, and others that the owners had me put a test pipe on, there was a noted lean hesitation that wasnt there before. In my case, that hesitation wasnt there after I re-installed my converter.
There is some restriction in a strata-type converter, which serves to keep the mixture in the combustion chamber longer for a more complete burn. Without this restriction the engine can run lean, just like installing a motorcycle low-restriction exhaust can cause lean "flat spots", needing mixture correction by rejetting(carbs) or a power commander(FI).
A lean mixture will cause higher combustion chamber temperatures, akin to turning up the oxygen on an oxycetylene torch to get a hotter flame. This hotter combustion temp heat then transfers to the cylinder head and coolant, and the temp reading will rise. In short, a lean mixture can cause an engine to run hot.
If the converter had been clogged, you'd have a power issue. And if the car was OBDII, you'd generate a catalyst efficiency code.
 

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I just have a slip on and am quite happy. I also assume its the cat that dulls the sound some. Much quieter than my 05 650(Almost perfect). Took away my low RPM flat spot.Extra power? Not by much, but if that were the problem I would of bought a different bike.
 
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