Ok, I admit it. I am a compulsive modifier.
I decided that I has to do something about the stock exhaust. It's quieter than an electric bike.
On my 04 DL650 I had completely removed the pea shooter from my bike. Despite this radical modification, it wasn't very loud, but it did sound a lot better. It was about 93dB. My mates stock Yamaha MT01 was 94dB.
I attempted the same thing on my 2012 G-strom. I thought it would be quieter, as it has a catalytic converter which normally does a good job of muffling sound by itself. So here are the pics;
The exhaust is a similar design to the old one. The end plate is much more painful to remove, as it is welded on. I was very very careful and managed to grind away the welds with the exhaust still on the bike.
The sound comes from the front, and goes throught to the back chamber by the first of 3 pipes. It then goes forward into a middle chamber through what some call a resonance tube (2nd pipe). It then finally goes from middle chamber into the pea shooter which brings it out the back.
By removing the pea shooter you make the exhaust a lot more free flowing, it basically just goes through the first pipe and then out the back of the bike.
I did this mod on the 2012 G-strom and it strangely was a lot louder than my 2004, despite the catalytic converter. It also made a crappy farting sucking noise when you released the throttle and let the revs come back down. I am a little puzzled as to why the 2012 does this, when the 2004 didn't. Anyway, this is how it is.
Do I had to remake a shortened pea shooter. I need to take some more pics of these next stages. But what I did was make a short pea shooter mounted to a round flat plate which sits inside of the outer pea shooter pipe. The short pea shooter added a little restriction, but still allowed the exhaust gases to bypass the middle chamber. I started it back up and it still made the weird sucking farting noise when releasing the throttle.
So I removed my shortened pea shooter (which I have made attached with a single bolt) and put a 45 degree bend extension on it. My aim was to make the exhaust gases come into the rear chamber and have to turn a little before coming directly out the back of the shortened pea shooter. I started it up and now have a pretty good comprimise on sound. I re-attached the chrome end cap with a couple of rivets near the bottom, where they can't really be seen.
Cruising along there is almost no difference in sound. When accelerating hard it makes a little more noise. When idling and cruising below 40kph you can hear it's a little deeper and a little noisier.
It will do until I get around to buying an aftermarket exhaust that I like the look of. If only the Akro had a catalytic converter to make it legal...
I decided that I has to do something about the stock exhaust. It's quieter than an electric bike.
On my 04 DL650 I had completely removed the pea shooter from my bike. Despite this radical modification, it wasn't very loud, but it did sound a lot better. It was about 93dB. My mates stock Yamaha MT01 was 94dB.
I attempted the same thing on my 2012 G-strom. I thought it would be quieter, as it has a catalytic converter which normally does a good job of muffling sound by itself. So here are the pics;
The exhaust is a similar design to the old one. The end plate is much more painful to remove, as it is welded on. I was very very careful and managed to grind away the welds with the exhaust still on the bike.
The sound comes from the front, and goes throught to the back chamber by the first of 3 pipes. It then goes forward into a middle chamber through what some call a resonance tube (2nd pipe). It then finally goes from middle chamber into the pea shooter which brings it out the back.
By removing the pea shooter you make the exhaust a lot more free flowing, it basically just goes through the first pipe and then out the back of the bike.
I did this mod on the 2012 G-strom and it strangely was a lot louder than my 2004, despite the catalytic converter. It also made a crappy farting sucking noise when you released the throttle and let the revs come back down. I am a little puzzled as to why the 2012 does this, when the 2004 didn't. Anyway, this is how it is.
Do I had to remake a shortened pea shooter. I need to take some more pics of these next stages. But what I did was make a short pea shooter mounted to a round flat plate which sits inside of the outer pea shooter pipe. The short pea shooter added a little restriction, but still allowed the exhaust gases to bypass the middle chamber. I started it back up and it still made the weird sucking farting noise when releasing the throttle.
So I removed my shortened pea shooter (which I have made attached with a single bolt) and put a 45 degree bend extension on it. My aim was to make the exhaust gases come into the rear chamber and have to turn a little before coming directly out the back of the shortened pea shooter. I started it up and now have a pretty good comprimise on sound. I re-attached the chrome end cap with a couple of rivets near the bottom, where they can't really be seen.
Cruising along there is almost no difference in sound. When accelerating hard it makes a little more noise. When idling and cruising below 40kph you can hear it's a little deeper and a little noisier.
It will do until I get around to buying an aftermarket exhaust that I like the look of. If only the Akro had a catalytic converter to make it legal...