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After riding with both exhausts for about 60 miles each and under the same riding conditions, I found that the Rush pipes performed much better than the Straight Shots with no baffles and TTI's installed.
With the Striaght Shots on, the bike was weak on the launch and took a bit to really start pulling. They felt decent on the upper end from about 4500 RPM on up to rev limiter. They were not any louder than with the baffles installed and they still had that raspy/tinny Vance and Hines sound.
With the Rush pipes on, the bike is much stronger on the launch and pulls hard all the way through the RPMs. The bike jumps up and goes with any twist of the throttle and has no hesitation like it had with the Straight Shots. The sound is much deeper and a bit more quiet at idle but they get pretty loud when revved up.
Even with the TTI's in the Straight Shots they just didn't perform that well. When I had TTI's installed in my 3" stock mufflers, the bike ran very well. Not sure why the results with the Straight Shots were not nearly the same. I know TTI's do improve the performance of pipes and they did improve the Straight Shots but the Rush pipes are just better performing pipes hands down.
Better performance on the high end only sounds like low back pressure from the pipes. Strong launch and good mid range pull comes from a good exhaust back pressure level, without other significant changes on your motor. Your efi map, if it's still stock, is off for the reduced back pressure and may not be able to compensate for that much change. The Rush pipes are probably closer to stock pressure so work better with your current efi map. In real world riding, lower back pressure with little else done for performance, can give you a bit more top end and high rpm power, but closer to factory back pressure will take a hill against a headwind in high gear better. It's even more noticeable on carb motors.
Better performance on the high end only sounds like low back pressure from the pipes. Strong launch and good mid range pull comes from a good exhaust back pressure level, without other significant changes on your motor. Your efi map, if it's still stock, is off for the reduced back pressure and may not be able to compensate for that much change. The Rush pipes are probably closer to stock pressure so work better with your current efi map. In real world riding, lower back pressure with little else done for performance, can give you a bit more top end and high rpm power, but closer to factory back pressure will take a hill against a headwind in high gear better. It's even more noticeable on carb motors.
Thanks for the info. I have a Power Vision tuner and have a map specifically for running TTI's supplied by DK customs flashed to the ECM. I ran both pipes with the DK map and the Rush pipes did much better. The Straight Shots were always weak on the lower end, baffled and with TTI's but did a bit better with the TTI's.
Installed my DIY breather on the S&S and took her for a 25 mile jaunt to see how it worked.
I've got a little decel popping and stumbling in the mid range, so there will be some re-jetting coming up, but only after I install the Lowbrow Customs Shotgun exhaust I've been eyeballing for awhile.
I took the bike outside today to check some things in the daylight. Can't ride, roads are full of salt. Maybe later this week.
Stainless pipes at the engine are indeed blue. Dealer says it's normal. It's a holiday here today so I will find out tomorrow if they made the required adjustments when they installed the pipe and SE air cleaner.
Can't ride because of weather. Snow melted, now it's raining. I'm really reaching now...
Went down to the garage and put the bike on the lift, and checked the front wheel for trueness. It's coming up on 30K miles and I've never checked the spokes other than the tap/ping test once in a while.
Well, there was a distinct spot where the wheel was out of spec laterally. I tightened a few spokes a quarter turn, spun it & checked again. Repeat. I was able to get it where it needed to be before too long. Amazing, it worked, and I didn't break anything. Life's small victories.
02-17-2018, 10:51 PM
