It's not every day we're accused...
It's not every day we're accused of being filthy liars...
Your last article on loud pipes was good and I have been thinking of a change. I currently ride an 2002 426 with a White Bros. R-4; this is a loud pipe and I am conscious of my noise output. But I felt one thing deserved commenting: Be honest.
When you started to play down your own dyno test results to make the point that power loss of a quiet pipe was not that bad, I just about put it down. It starts to remind me of the government telling me that my brain was an egg and a frying pan was drugs. Now I know that my bike is no egg... and the environmental extremist are not frying pans so lets please stay away from bad analogies and out right lies to make our point. The facts are always better than hype.
Overall it was a good article and did push me over the hurdle to get a new pipe. On a internet search of quiet pipes I found few, if any, at a good price. Currently, they are few and expensive. I suggest looking hard forand publishingresults of good alternatives in quite pipes.
Many have made a good investment in their exhaust systems and are not going to rush out to spent hundreds more for something they didn't really want in the first place. The aftermarket guys will have to make these things cool by performance and style. And if one of them wants to truly stand up and do the good thing, they would sponsor a "send us your old one for a quiet retro fit" kind of thing (good idea, right?! Go ahead and use it; just send me 10% for the idea).
Dave Hannibal
Eastern Oregon
Although it's a useful testing...
Although it's a useful testing tool, HP dynos are not a direct measurement of your bike's power.
We didn't play down dyno results, we downright blasted them. They are great for looking at a line on a chart that describes a theoretical performance factor of your motorcycle engine, but does little to tell you what the pipe does for your bike.
A dyno is a sales tool. It is a consistent testing tool for those who understand how to use the information it provides, and peak HP isn't the information they are looking for.
Generally, with a properly tuned quiet exhaust, you will get more peak HP, on both two and four-stroke motors. Look at the chart published with our 250cc MX comparison for reference. With the proper jetting and additional back pressure, peak numbers are generally better. What the dyno doesn't show is that the rate of RPM increase in usually slower, giving the rider the feeling of less snap and less power. Smart riders tend to twist the throttle farther to compensate for this. A lot of riders actually end up riding faster because they end up with better traction. Believe me that the "excitement" of the fast and abrupt hit of an uncorked motor has a lot of fans out there, but few can actually use that type of power.
I'll reiterate the most important part about the dyno implication: You do not ride a dyno, nor do you ride your bike in conditions anything like what a dyno tests at.
There are no lies in that story and I take offence to that statement. I have worked with a lot of pipe builders and I know what properly quieting down a bike does. Killing power isn't one of them. The biggest problem is that most of the pipe manufacturers are not building effective sound deadening designs, they are just corking up existing mufflers with smaller holes. This will kill power when the outlet isn't right. Properly designed quiet systems, like FMF Q or a Leo Vince X3, put out stock or better power levels, even on motocross bikes.
As far as your retro fit suggestion, it is goodany way we can to quiet up bikes right now. But hopefully more riders will think twice about putting a loud pipe on. That is the first step we are trying to push so we don't loose more riding opportunities.
And Dave, crack killed Apple Jack.