The popping/backfiring is due to an overly lean condition. Rejetting is a trial and error experience.
You probably put a small pod filter on the crankcase breather hose. Be aware that the inside of the filter can become blocked by oily goo, resulting in too much internal pressure which will blow out the left side oil seal
Keepin' all the left over parts. Gonna use 'em to build another bike!
I just put the filters on their brand new and it loses power and starts popping over half throttle idles perfect starts perfect easy acceleration it runs perfect just hard acceleration is when it starts having issues
It sounds like your issue is with your main jet selection based on how you describe when your problem occurs. My bike is stock, and runs very well. With everything stock, at WOT, my bike is rich. Way rich. It is about 19% richer than 12.5:1. And at 12.5:1, it remains rich (and safe). And mine stock, is way richer than 12.5:1. 12.5:1 is very safe, and is the AFR that produces maximum WOT power with gasoline. Mine is running about 10.5:1, at best at WOT. When I first whomp it (below redline) it hits about 9.0:1. And works its way up to 10.5:1 (with more airflow) at near redline.
My opinion is, that carbjetkits is a company whose job it is to make money. In order to make money they have to sell. The only true way to know how to jet your bike is to run an AFR gauge on it. Or, to have someone else with the same or similar set-up run an AFR sensor, and tune. Then match their tuning. Read through that linked thread. I hope my contribution will be worthy.
I'm in process of tuning my stock bike. Unfortunately, I've been on a long sabbatical away from my bike due to my Mom being in the hospital, then passing away. Followed by my dad being sick this past week / weekend. Hopefully this evening, I'm going to start gathering data. The weather looks good. So maybe I'll get some runs in.
2016 Honda Rebel 250 - The "Piglet."
Totally Stock at the moment.
Bought on 6/29/19 with 44 miles.