exhaust for XR650R

[chuckinketchum]

I put street tires on this bike and never use it in the dirt. Which exhaust is gunna be best. I don't care about noise, I live in a remote area. I want power. What exhaust gives the most power and adjustability? How much power gain am I gunna get? Is it worth it or should i go buy a new trials bike? Thanks , Chuck

[BrianVT]

Drill the stocker, uncork the intake, rejet. $50 tops.

Then go get the trials bike.

[big t]

I've heard good things about the stock exhaust also. I'm running the stock drilled out exhaust until I have the money for an exhaust but I will be getting some other goodies before the pipe. If you want the looks and some power check out the Moriwaki. I'm sure some more guys will respond that actually have the Moriwaki.

[jazzeyb]

I'm running mine gutted.... Love it ! But..... I do like the aluminum look.... My buddy is running a Big Gun on his '04 XR650L, and I'm a-lookin' pretty hard at the White Bros E Series.. If I do that, then I'm going to try and (first) wrap my headers... Then if that fails, I'm gonna try the ceramic coating...

[smashinz2002]

Once again,, the aftermarket pipes that I have tried are total crap, don't fit right, cost a ton of money, and fall apart pretty quick, or leak, or both.

The 650R comes with some good stock headers and silencer, but it has to be modified. Uncork the bike, rejet, and run the HRC exhaust tip from honda. You can also modify the HRC tip by removing the arrestor screen. Also, some of the guys modify the stock silencer itself (not the tip), by doing various things to the internal baffle plates.

THIS BIKE IS NOT A 250, so aftermarket pipes arent going to "add" much power, if ANY! Mainly what they do is move the power curve around, usually up the rpm scale, at the expense of low rpm power. This bike is not a revver anyway so I really don't get that idea. I guess it helps if you're running it flat out all the time, I don't know though.

I thought the Big Gun race series headers made the 650R feel kinda "flat" and personally I thought it made the bike feel slower and not as fun. Especially at low rpm it ruined that "trigger happy" feeling that the stock headers provide at low rpm.

[chuckinketchum]

The stock header comes out and decreases in size. I can't believe a new header doesn't give more flow. Can I use just the new header and keep the stock exhaust? What about the HRC kit? The one with titanium valves and a new cam?

[qadsan]

I can't believe a new header doesn't give more flow.

A larger header will increase the flow volume, but it will also decrease speed of the exhaust and that isn't always desirable. More flow doesn't always equal more power and that's true with the exhaust, the flow through the carb and through the cylinder head. The flow has to be carefully balanced to get the most from it. With a stock uncorked XR650R, a larger header can help with making more power at higher RPM, but at the expense of some low end power, which is something you may or may not want to give up depending on what you're after. Don't assume that all the aftermarket parts you see for the XR650R will increase your bike's power because that's not always the case. Sometimes they do and sometimes they don't. Sometimes they actually loose power over the stock components. Sometimes they increase the power in a certain area, but at the expense of power elsewhere. There used to be an interesting article titled something like "XR650R pipe shootout" in the Yahoo XR650R group file section and this article compared various exhaust systems with each other and their dyno results. The exhaust systems tested were from White Brothers, Stroker, Pro Circuit, Big Gun, FMF & Yoshimira and none of the systems tested made more than one peak horsepower more than the stock HRC system. Some systems lost a significant amount of power somewhere in the curve (i.e. 5 HP!) when compared to the stock HRC exhaust. The White Brothers E series was the only product tested that actually made slightly more power everywhere. This article is a few years old and I'm sure some of the pipes have changed since then, but it was a real eye opener to some people who thought they were getting more for their money.

The HRC kit with the high compression piston, new cam, etc, is a nice option, but even Team Honda doesn't always use the complete kit. From what I gather, they always use the HRC cam and other components, but don't always use high compression piston. Check out this article for info on how the Honda Off-Road Team builds Baja bikes.

http://www.hondaredriders.com/insideline/currentfeaturedetail.asp?ArticleID=361&Type=OR&bhcp=1

[chuckinketchum]

Thank you-- I came close to spending $450.00 for just nothing.

[qadsan]

It might not be for nothing, but do look carefully at your purchases. For sure a new pipe has the bling factor and that counts for something (I like the bling too!). If you're flat tracking or riding a lot in the upper R's, then a larger header would make more sense to me. If you're planning to install a new cam and or have your head ported and or use a high compression piston, then these things can bring back the low end power that might be lost with the use of a larger header, so keep that in mind too. For trail riding or general purpose fun or for some types of off road racing, the stock header is really hard to beat in terms of price / performance. If you're looking for something specific on where you want more power delivered, then an exhaust system can be tuned to deliver on your needs.

It's super hard not to be impulsive at times, but if you feel the urge to buy, then take a step back and do some homework on what you're buying. This has saved me numerous times when buying cars, parts, windows, bikes, etc. If you send me a PM with your email address, I'll send you a picture of the dyno charts from that article, but remember these tests were conducted a few years back and things may have changed since then.

If you're ever in doubt of how a product affects your bike's performance, then get your bike dyno'd in its current form. Then while the bike is still on the dyno, bolt on your new part and make a few more runs so you can get a true comparison of what has changed. It's more expensive to do this and not very convenient, but you'll know for sure just how well your aftermarket part has performed. If that's not possible, then try to find someone else who has done this and use their bike as a benchmark. $450 is a decent chunk of change no matter whether its for a carb, pipe, suspension, etc, and its no fun when you're purchase doesn't meet your expectations. It's got to the point where I don't always believe what the aftermarket manufacturers tell me in magazine adds, especially when it comes to aftermarket parts for cars because it doesn't always work out perfect. If a product is getting good reviews from numerous people who actually use the product, then its much more likely the product offers something pretty real, but don't forget that marketing along with the placeebo affect can sometimes be quite powerful. There used to be a craze with certain spark plugs that were supposed to give you a horsepower increase and some people swore they felt a good performance increase. The Federal Trade Commission found that many of these products did not produce the results being advertised and put a lid on them, but there was a craze for a while where people were paying much more money in hopes of getting more performance and the product didn't deliver. The same thing has happened with oil additives and numerous other products that have been sold with clever marketing with performance in mind.