I dont want to spend over $250 and I really dont want to have to re-jet. How does a White Bros. R4 S-Bend aluminum silencer sound? Does it make a noticable differance and do I need to re-jet? Also has anyone heard of the RCR performance silencer? Same questions for it if anyone has. Thanks!

 

I have the R4. It is really loud. I thought my DMC full system was loud then I put the R4 on my other bike and its just as loud or louder. Its nice though. One thing I don't like about the
R4 slip-on is they make it two pieces, when they could of made it one. I took my air box lid off, added a KN air filter, ground out the header welds, removed the choke, and yes rejetted. Even if I was just adding the slip-on, I would rejet. I raced my son in a short race and beat him. He was on the quad with the DMC. But then we switched quads and I beat him again, so I guess I didn't tell you anything. But he thinks the DMC quad is faster. But I think if it is, its barely. I put the stock 158 jet in and that might be a little rich, so I will try the 155 and see how that feels. Rejetting isn't that beg a deal. And if you need help, you always have this board. The insructions with the R4 say you don't have to rejet, but you probably should to see a bigger increase in power. I paid $211 for my R4 with free shipping.

 

Where did you get yours from? I just want crisper throtle response, not power.

 

parts direct I got it here. They have good prices, but take their time shipping. It took me like a week and half to get my pipe. You might get a better response with your 400ex questions at Exriders.com if haven't already tried there.