I'm pretty sure if they are going to hate me for how loud my motorcycle is, they already do. My other sport bike is LOUD. Not straight piped, very similar design to Deans(smaller muffler body due to fairing constraints), but I think two cylinders lend themselves to open exhausts better than 3 or 4 cylinders. The twins have a nice deep rumble with an open system, the 3 or 4 cylinders are more ear splitting loud. If my neighbors have been able to put up with that, I don't think they will mind the EBR.
I think Dean said his system was around 98 at idle and 110+ at 5000rpms. I had my other sport bike tested and it came in at 107 db at idle 2 feet from the exhaust and 99db from 10 ft behind the bike. Also hit 110db at 5k from 10 ft behind the bike.
Last edited by 1190SX; 02-10-2017 at 08:16 PM.
Dean on your web site you have 3 different cans for the SX , what are the differences ,and which is best for scooting around on mountain roads and not too loud?
Thank you in advance.
I think its just two different set-ups with different ECM options (Fully programmable or locked race ECM with Deans tune) One has an oval muffler body, and one has a round muffler body. The programmable ECM is for those who want to further dyno tune or modify the mapping.
I ordered the oval body, as my scientific research indicated oval muffler bodies absorb slightly more sound.
It was picked up Sat , hope to have it Tues, I will be riding it soon !!!! I can taste it .LOL
Last edited by EBRRider; 02-11-2017 at 02:09 PM.
EBRRider: I also went with the oval body exhaust, ordered mine today!
Hmm, interesting thought.
In vaguely related field, jet engine test cells use a oval cross section exhaust duct/muffler as well. A jet engine test cell is basically a building where they bolt a jet engine down for operational testing. The exhaust from the engine is directed out the back of the building through a long ~10 FT diameter pipe and then against a baffle which directs it upward. The pipe is constructed basically like a big glass pack muffler; with a solid outer shell, a bunch of lead and steel wool, and perforated inner panels. There are also baffled air inlets to the building to provide air to the engine while it's running. The whole idea is to absorb sound so you're not shaking the windows out of nearby buildings while you're testing the engine at WOT. Here's a picture of one i worked on at NAS New Orleans some years ago:
Up until recently, the ducts were oval in cross section. Then somebody did some experiments with a scaled one made with a square cross section, which would be much simpler to fabricate. Turns out the square one did an even better job than the oval one of killing the sound. I'm not sure if they've built one yet; a couple of guys I used to work with were trying to push a project through to build one like this but their boss was EXTREMELY conservative and nixed the idea.
Anyway, it occurs to me, maybe a square cross section muffler would work better at absorbing sound.
OK- who's gonna try the first square cross section muffler?