Posted by George on September 01, 1999 at 04:51:36:
The SuperTrapp exhaust system is tunable. The Savage model is a megaphone that comes with 8 discs and an end cap. Apparently, the more discs you install, the leaner the bike runs and the louder it gets. After experimenting, I’ve settled on five discs. I’d like to use six, because I prefer the additional sound volume, but the bike runs better with five. The trade-off seems to be mostly between what I call the “high end” in lower gears and the midrange in higher gears.
With the stock pipe, my Savage is torquey but quite limited in the top end of the first two gears. That is, I'd quickly reach a point in first and second gear beyond which the bike just didn’t want to go. For me, that point was much too low: as I recall, it was around 20 mph, for example, in first gear. Using six discs in the SuperTrapp completely eliminated that feeling of running up against a wall in the lower gears. It also increased farting; almost every gear change evoked a pop, often quite loud and sometimes visibly startling to automobile drivers. And it made a good loud sound overall, too, loud enough to wake up daydreaming cagers on a number of occasions. (They don’t seem to think to LOOK before changing lanes; we really are invisible sometimes, so, in my opinion, if we won’t be seen, we should try to be heard.)
Unfortunately, the six-disc configuration also weakened the bike’s power in the upper gears, particularly in the midrange. (I believe that the infamous plastic spacer in the carb controls midrange fuel flow, but I’m not willing to remove that just yet: the bike’s still under warranty, and I don’t want to modify the carb now.) Apparently, the bike was running too lean. My option -- and this is the great benefit of the SuperTrapp -- was to tune the system by changing the number of discs installed. Removing one disc restored the power in the higher gears and added a more torquey feel all through, even in lower gears, but it also reduced the high end of the lower gears – not nearly, however, to the low level they’d had with the stock pipe. It also reduced the farting. (One strange effect is that the bike seems to need a longer warm-up now; if I don't warm it up for a long time, it cuts out.) On balance, the trade-off was not a bad compromise.
The SuperTrapp is expensive (about $215 US), it was a pain in the butt to install (I had to have the headpipe cut and welded), the sound has a tinny aspect, and half my pipe is gold (yellowed) rather than chrome-color, but the tunability makes all that worth tolerating. The performance gains are impressive, and the sound, tinny though it may be, is decent. I love thumping around town and pounding up hills on country roads, and the Savage’s blatty roar when accelerating at high speed on the expressway is an indescribable pleasure. And off the highway, even with only five discs I still set off alarms’ warning signals as I thump by parked cars -- the perverse pleasure I get from that is almost worth the price of admission.