Loud Bike - I'm stumped

I know people pay alot of money for a louder bike/pipe but I'm stumped at what might be causing my 2012 gsxr600 to sound like its got an after market exhaust on it when its got the stock can on. Was out this weekend riding around, bike starts, runs, idles and revs fine. Lots of power when I hit the throttle too. But the bike just sounds sooo much louder than last year. Riding up a somewhat steep hill on the Niagara escarpment this past weekend, at one point it almost sounded like a v-twin or a cruiser it was so loud. Thats the loudest It's been. Dropped it down a gear but was still loud. At that point I started to worry that something was really wrong. On the highway home it sounded louder than it should. Still had power etc though. It sounds normal in certain gears just cruising, for example 4th gear around 5-6k RPM it sounds normal. I find that under acceleration is when it sounds louder than normal, yes I get it that it 'should' sound louder under acceleration but not like this.

I replaced the spark plugs last fall, they had 18K on them and the bike was starting to have a bit of a hard time starting. It actually stalled on me once as I rode away from the house. So changed the plugs, oil/filter before I put her away. Changed the air filter this spring. When I did the plug change last fall and put her back together I started her up and she sounded like a diesel, took the airbox off again and one of the hoses that goes into the top of the engine beside the center plugs was off. Put it back on and she sounded good again.
I've taken the airbox off 3 times now in the last couple of weeks thinking that somehow I still have a hose or something off... if there is I cant see it.
Could I have thrown something out trying to get that damn airbox back in? Its so tight you really need to push on it. I notice the throttle cables on the left side of the airbox get pushed around a lot when doing all of this.

I'm stumped..... thinking I should get it into a shop and have someone that really knows what they are doing look at it.

If it is still running just a well as it was prior to the noise increase it could be that the packing in the muffler has burnt off, although that usually only happens with cheap aftermarket mufflers. Another possibility is that an exhaust clamp has come loose and exhaust gases are escaping. Lastly check your headed bolts to ensure that the header pipes are making a good seal on the block of the engine.

Leaking head gasket?

Almost sounds like airbox lid or intake snorkel missing. Just a generic observation, not intimately knowledgable on Gixxer 600.

Your stock baffle could be damaged. If all power is the same and noise is the only change sounds like either what the above posters have mentioned or the stock baffle fell out or is damaged.

I don't think it's the head gasket...

Do you hear that same sound revving the bike while stationary?
Closely check all hose at the air box to make sure all is connected, make sure the air filter is seated properly and the lid is closed tight all around.
Is it OEM exhaust? how old is it? As mentioned above the packing might be gone... maybe a mouse stole it to make himself a castle in your garage somewhere....

Rob said:

I don't think it's the head gasket...

Do you hear that same sound revving the bike while stationary?
Closely check all hose at the air box to make sure all is connected, make sure the air filter is seated properly and the lid is closed tight all around.
Is it OEM exhaust? how old is it? As mentioned above the packing might be gone... maybe a mouse stole it to make himself a castle in your garage somewhere....

Click to expand...

It does have a slightly louder/deeper put put put sound at idle but not much. I mainly hear it under load when accelerating. Going up the hill in Niagara obviously under load was the loudest its gotten. I've checked the airbox 3 times now. Everything is connected and tight.
OEM exhaust. I always stuff something into the tail pipe in the fall to stop mice getting into the exhaust. They'd have to be a magician to get by it as it was still there this spring and in good shape.

I'll check the header bolts and exhaust clamps...

Louder in what way? Exhaust or intake? Spark plugs at 18,000 really? Mine are stock with 54,000 and 20 something trackdays. More likely air filter was dirty. You put a new air filter in, is that when you noticed it was louder? If so the old one was really dirty.

Copper exhaust gaskets wearing out?

Dissassemble the stock exhaust, and put new high temp rtv sealant on the midpipe connection.

Yep, check all clamps.

matt365 said:

Copper exhaust gaskets wearing out?
Dissassemble the stock exhaust, and put new high temp rtv sealant on the midpipe connection.
Yep, check all clamps.

Click to expand...

If the exhaust has never been off the exhaust gaskets should not be wearing out. Check to make sure that all bolts on the headers still have nuts - could be (but unlikely) that some have worked themselves loose or fallen off.
Make sure mid pipe clamp is tight.
Check for rust - any holes anywhere?

I would suggest, as others before, check all clamps.

You finally cleaned your ears.


This used to be my signature, but Paulo didn't like it.

Are you wearing a new helmet? I had this happen to me, started wearing ear plugs as new helmet was louder than old.