Hi all... I got very strange case when I replaced my EU honda1000cbr 2014 stock exhaust by a universal pipe and muffler only.... My top speed not passing 289....i lost 10km and a lot of power and I don't know the reason..... Is it the back pressure effect.? Or o2 sensor is reading different flow in the exhaust that's why sending lean messages.?.... For information I returned back stock one and I got my top speed again.... But up to now I don't know what happened
No all are stock.... This first change to be done in the bike.... But it's only pipe and muffler.... Header is stock
You're likely running fairly lean especially at high rpm. The bikes fuelling is programmed based on the stock exhaust.
The difference between a mapped and unmapped exhaust can be several BHP maybe 10 BHP. Up in those lofty RPMs the AFR is probably way off optimal.
If running leaner up top the bike would likely be making more HP not less. You sure your not simply pushing the bike less hard because the exhaust is louder? What rpm are you shifting at? What rpm did you shift at last time you went faster? Are you sure you went 299kmh last time? Same road? What was the wind/ambient temp of the day you ran 299kmh? Did you run to the rev limit in each gear when you ran 299? Are you trying o run from 250 to 299 int he same gear? A lot of reasons why you might be slower now.
There is no learning of anything with regard to these Honda ECUs. No long term trims or short term trims. The O2 sensor is a narrow band unit that is only active in low rpms.
I believe the CAT is in the silencer on the 2014. The aftermarket silencer: does it have a CAT, O2 fitting and exhaust valve? If you have no CAT or valve, then maybe the exhaust backpressure is not right for the engine (altough the valve fully opens past 4000rpm). The OEM on my RR8 has 2 chasmbers in the silencer and once internal spring loader valve in addition to the servo driven one. A rolling road power run would deffinitely tell you what's happening with the power
