Brand new 2013 Yamaha R1 with the stock exhaust vs the Two Brothers Black Series M2 Slip-on exhaust system with both the standard and P1X Power Tip sound suppressors installed. Bike had 400km on it when the exhaust was installed.
Stock the sound is actually quite nice out of the R1 with the cross plane engine. It sounds significantly louder/better than most. With the Two Bros exhaust installed it was a night/day difference in sound. Extremely loud and very deep and throaty. Sounds like a V8 muscle car. So loud it'd set off my neighbours car alarm and I had to wear earplugs when I rode it.
I then installed the P1X tips and it significantly reduced the sound. Idle isn't as noticeable as it is when moving/revving the engine. It still sounds great and lets the engine breath the way it should, but it is a lot more tolerable when riding it and I think I'm going to keep it that way unless I'm at the track. There has been no ill effects as to how it runs with just the slip-ons installed; no other engine modifications have been completed (cat and ecu stock).
Fit, finish, and instructions were all high-quality (and packaging was amazing too). A solid product that looks and sounds great. I've only done 1000km since install so I can't comment on the lasting good looks of the system, but so far I'm a happy customer.
Feel free to comment/ask any questions, thanks!
