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Discussion Starter #1
Have a 2016 Cbr300r, havent had to many issues and do all maintenance myself. I'm not expert by any means but have worked on engines for awhile and get around fine. Was wondering why I'm back firing so hard at 8200+ rpms. I have a full arrow gp2 exhaust kit on but have yet to fully tune or remove ECU. It has gotten gradually worse over time and am trying a swap out with the stock to see if its just to large and needs the tune out before replacing. Any thoughts would always be welcome. Thanx 馃憤
 

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Is the back fire just on decel? And has it been the same since you fitted the Arrow system or is it a new thing? If it鈥檚 always been that way then a custom ECU flash would sort it out but it鈥檚 not a cheap exercise.
 

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+1 on what Kiwi said. Any time the catalytic converter is removed, and the OEM exhaust has bee opened up with a more free-flowing exhaust... you'll have problems until the ECU is re-flashed or you install a controller to address the issue. My mechanical skills are old school... if I can see it, and it requires a wrench and socket, I'm probably capable. The problems caused by an exhaust swap effect the air/fuel systems and are controlled by an ECU... Way above my pay grade. :whistle:
 

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My CB300 was noticeably down on power with a full exhaust and no compensatory tuning.
 

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Discussion Starter #5
I lost power with my full exhaust as well. I pop on decel due to my large exhaust, its the high rpms that kill me. I lose speed and its a hard jerk. Pretty much come down to too rich on fuel not enough air. I removed upgrade and installed stock exhaust. Obviously made a huge difference in speed and no popping. I've upgraded enough that I'll too out at about 115 mph even on stock exhaust. Eventually I'll just by the pocket tuner I've been looking at and remove the ECU completely and be technically track ready. But I'm in the states and get away with it on the street.
My CB300 was noticeably down on power with a full exhaust and no compensatory tuning.
 

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I lost power with my full exhaust as well. I pop on decel due to my large exhaust, its the high rpms that kill me. I lose speed and its a hard jerk. Pretty much come down to too rich on fuel not enough air. I removed upgrade and installed stock exhaust. Obviously made a huge difference in speed and no popping. I've upgraded enough that I'll too out at about 115 mph even on stock exhaust. Eventually I'll just by the pocket tuner I've been looking at and remove the ECU completely and be technically track ready. But I'm in the states and get away with it on the street.
What did you do to your bike that makes it able to top out that high if you don't mind me asking? Thanks!
 

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Discussion Starter #7
Honestly not as much as you would think. Between just getting lighter parts, vortex sprockets and chain, k&m airfilter and opening up its ability to breath. At stock exhaust with passenger I've pulled 110mph. It has slack in the chain, throttle, and clutch. I do not suggest reducing chain slack and I'm sure people will tell me I'm an idiot for doing it. But it works. I've swapped between the stock 14t and a 15t front sprocket its -/+2mph (tested by radar and a few tickets) so what reads 115 is actually 113 and the 15t can't hit 117mph (actual 115mph). 15t tops out at 111mph or actual 113mph.
What matters most is make it as light as possible the lighter the less strain at 10500rpms. I wish I had chosen a cb300 as its already lighter and opening it up would have been a hell of a lot easier. I coulve even changed the mapping to a cbr300r... Hoping that tuning it to my new exhaust it'll pull 118mph. Only in theory though. I won't know till its installed. I'll keep it posted. Sorry no pics and it wasn't as exciting as you may have hoped.
 

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The CBR is more aerodynamic than the CB so should be a bit faster.
 
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