Over all I think this was a great pipe. I liked the fact that the mid pipe and the silencer was one piece and didnt need all the extra parts and problems. It sounds great and is not to loud to have to worry about the police or the neighbers. Performance gains were very good. I didnt like the FMF sticker on it. If it would of been a plate that may last longer it could of been a perfect 10!! Great price!!
I put this muffler, matched with a powerbomb header, on a 04 XR400R and it was a good investment. It gave the bike some much needed power. The sound is great, its quiet but at the same time its loud, when wanting to keep the sound down and upping the power you can't go wrong with the Q4 its the way to go.
I don't think any exhaust is going to be super-quiet, without affecting performance. This is definitely more quiet than the White Brother E-Series exhaust it replaced. That one ran almost 100 dB. This one maxes out at 96 dB. It doesn't seem like a lot, but it is on the ears. I would recommend this for anyone looking for a quieter exhaust. Even though the stickers have foil on the back, on recommendations from other reviewers, I took them off before running it. Still looks cool.
I have always been happy with all of my FMF purchases in the past and this was no different. Installed on a 2009 Yamaha YZ250F with stock db rating of approx. 98. After install, downloaded noise application on phone and it registered 87-92 db's.
I love the ehaust but trying to put it on with the rubber seal was a pain to get it just perfect. But it was cold and it all worked out. In all it was worth it. The 400ex runs good without haveing to re jet it. I would recommend this product for some one who wants just mid range sound. And the ehaust sound awesome.
Slip-on style muffler fit with some struggle they provide a strap to mount the muffler to the subframe and it appears like it was either tweaked or not formed right. It was a struggle to get the clamp around the muffler. Once on big difference. A little louder than stock muffler w/o S/A.
I put this pipe on my 09 KXF 250 and was very impressed with how quiet it is. It is more silent than the stock pipe and has some performance gain. I also put on the powerbomb header. The fit was perfect. I am with the other reviewers and don't care for the sticker on the pipe. Also the pipe is longer than stock. Overall I am very pleased with fit and the sound level. I was looking for a pipe that didn't echo through the trees..into the valleys...and then over the mountain tops, and had a spark arrestor and this pipe fits the bill perfectly.
Yoshimura RS2 exhaust would not fit my 08 DR-Z 400sm called the Yosh factory and was advised they have had other problems with shipments from the facotory. They did not seem to be very sympathetic to my situation, they wanted me to send it back to them and they would send me one they said would fit, but wanted me to pay for shipping. Didn't sound like a very good deal to me so I Returned the Yoshimura to Dennis Kirk and replaced it with an FMF Q4. The FMF fit fine but the craftsmanship was a little disappointing the sticker and the strap that mounts the exhaust to the frame make the exhaust look cheap. It sounds great and I did notice a performance gain.
After fitting an Australian pipe ( Which is where I live ) and putting up with it being waaaay toooo loud I decided to import this pipe. I had being told that it was one of the most quitest pipes around.
If you want it to be loud then all you need to do is remove the spark arrester.
Top product, top price, and most of all QUITE with some nice deep down tone. Hard to beleive its on a 250.
I bought the Q4 pipe for my 660 raptor, it really boosted the torque quite a bit. At idle it's not much louder than the stock pipe, but once u hit the throttle it starts barking pretty loud. I didn't have to rejet wich was a big plus. Installation was easy, it took about 20 mins. Not impressed with fmf sticker on it though. Overall its a great pipe, that produces considerable more power, I'd recommend it to anyone
This gave my quad the quiet when I want it and the loud when I want it loud. This is amazing it's super quiet when idling or at low rpm's and loud when revved up. It also added some torque to my quad. Alot more than I thought it would. I am very happy with this pipe.
Chose the Q4 since I had a hunch the Powercore would be too loud for residential and trail riding. Fitment was flawless, and it's not a loud as I thought it would be. Certainly less "barky" than the Powercores I've heard, with substantial increase in bottom end grunt. For those of you on the fence between this and Powercore, the Q4 is worth a few extra bucks if sound level is a concern.