View Full Version : Need a reccomended size of universal IDS2 for 81 Yamaha XT500

03-21-2009, 07:12 PM
I have a stock Yamaha XT500. I want to replace the stock muffler with a new universal. What would be the recommended size IDS2 (quiet core) for this bike? It is a 28HP 500cc singe cylinder enduro bike.


03-22-2009, 02:34 AM
If you don't mind, I'll take a stab at it. The Supertrapp Gurus are usually off on weekends and chances are won't know the diameter of every bike's exhaust pipe at the point where you will slip the IDS2 on (http://www.supertrapp.com/product_sections/cat.asp?CatID=33).

The solution is pretty easy. I had the same question last year about my road bike and here's the methodology. If your pipe is 1 7/8" you'll need the 2" inlet diameter IDS2 (and you'll need to crimp and seal the two together like I did (http://forums.supertrapp.com/showthread.php?t=434)). If it's 1 5/8" (<==greater than 1 1/2, for instance) you'll need the 1 3/4" IDS2.

I'd wait for them to confirm. Good luck.

03-22-2009, 10:24 AM
Thanks KZ. I looked at the mufflers again, I didn't realize that they are all the same size muffler with just different size inlets. I was concerned with back pressure and such, but i now see that's tuneable.
I guess my only question left is what is the advantage/disadvantage to 16" vs 19", or is it simply different sizes to physically fit better in different bikes?

03-22-2009, 12:53 PM
Length is mostly personal preference as I had the option of putting on a 13, 16, or 19" muffler, but prefer the shorter can. Take some measurements from the exit point of your header to determine if the can will have a decent mounting point, like in this YouTube video (http://www.youtube.com/watch?v=DRKoy4kzBUw).

As far as performance I get lost in the science behind sound waves and pipe length, but I cannot see how 3" will make or break your choice. The ability to tune your pipe to your jetting however will prove to be the coolest feature of all. Tune it for the altitude where you ride most, with the number of discs that gives you the best power/dB level for your riding style. Then as you go up or down in altitude, just add or remove a couple discs to compensate for that weekend's riding. That's how I do it anyway. :D

03-23-2009, 08:32 AM
The longer the muffler (same would apply with diameter) the more volume it has internally and the greater the ability to absorb sound.
On a lorge bore single cylinder, your better off trying to get the longer muffler on there.
Everything else KZ mentioned is correct and thanks for stepping in over the weekend also.
Thanks guys!