M4 2014-2020 Yamaha FZ-09 RM1 Full System Exhaust (Black)

Trash product and trash seller. Bought this M4 RM1 exhaust and after a couple of weeks the finish came off. I contacted M4 directly and they said they will not replace it. I sent several messages to this seller and after a week they denied my return without any explanation. Complete trash seller. Save your money and shop elsewhere and look for a better exhaust. This one also had fitment issues at the heads and leaks which causes additional popping. See for yourself on the photos that were taken at 1 month installed.

Well first the good ...THE SOUND...it’s by far the deepest throatest exhaust I’ve found and I love it ..if you want that sharp ...sounds like a cat caught in a hell storm ..High pitched ...I’m trying to blow it up....buy one of the others I listened to just about all the different makes and M4 sounds best to me...installation wasn’t to bad but here’s why 4 not 5 stars.. I had a very had time trying to position the muffler so it wasn’t touching my swing arm...I had to twist it to the point the O2 sensor wouldn’t reach the plug so I had to Re route the sensor. I included a picture of the gap between the swingarm and muffler and it’s about a 16th of a inch and it’s already marked up my swingarm but even with that I wouldn’t change it to a different system again the sound is vastly different than most the other systems available I hope the read this and take a look at spacing..I’m sure I’m not the only one who’s had that problem

Your browser does not support HTML5 video.  Exhaust arrived very quickly and packaged very well protected. Install was fairly easy and straightforward. Two things to note: the left flange nut on the left side (looking forward) header is partially blocked by the header pipe so getting my socket on that one to tighten it was a pain, recommend having a U-joint socket adapter or wobble socket to reach that one nut. Other thing is if you plan to plug the O2 sensor back in (a plug is included if you aren't) you will have to route the plug different from stock since the m4 exhaust has the hole on the opposite side. Other than that installation was good. This exhaust is EXTREMELY LOUD compared to stock it shocked me. Videos online do NOT come close to showing how loud it really is. Sounds amazing though completely changed the sound of the bike. Lots of popping on deceleration so a tune would be recommended.

Thing is bad ass and high quality. I recommend ordering the silencer from their website because without is pretty damn loud. Looks very good and sounds amazing. Great price. Installed the spacer thats included to bump the exhaust out from the swingarm and it doesn't even come close to rubbing.Overall great value.

Purchased this around last march (2019) and i must say it was at my door in about 30 hours clocked lol. Packaging was great came with everything needed and it looks and sound INSANE on my fz09....i have zx10 with a slip on slash cut abd this m4 is soo...deep and throaty the zx10 appears to be shut off while they are side by side !! Greatt system !!I didn't do a power commander or anything for it until now( 13,000 miles later) and it was great up the entire time bike didnt skip a beat

This exhaust is amazing! I was debating between the Yoshi and the Akrapovic but the solid black color goes well with the black accents on my FZ09. As for the sound, the bike roars and other vehicles definitely hear me now. Make sure you wear ear plugs! Going to get the ECU reflashed soon so I could have a better idea of performance. The bike is definitely lighter now. Don't think twice about this exhaust. It's definitely worth the price!

Very nice exhaust. It fit perfectly and was easy to install. Unlike other M4 exhausts it did not come with the dB killer baffle. The seller would not knock off .01 for the dB killer, because of the misunderstanding. However, M4 did make a satisfied customer

Sounds great. Doesn’t come with a baffle, which is typical, so it’s pretty loud. Used an app on my phone and did a little ride with it recording and hit 112-115db. 4 stars because it did not come with anti cease as it’s noted in the directions that it’s supposed to come with it.