Honda Shadow Forums banner
1 - 3 of 3 Posts

·
Registered
Joined
·
167 Posts
Discussion Starter · #1 ·
When parked and not under load, when I rev the engine it sounds normal. When at speed, usually 3rd or 4th gear, when I'm really getting on the throttle, I hear a rhythmic hissing sound coming from the exhaust. It's most noticeable when I'm riding close to a wall or bushes on the right side where the sound bounces back at me. Based on the engine speed and rhythm of the hisses, it sounds like it's coming from only 1 of the cylinders. What could be causing this? Remember it only happens when under load.
 

·
Registered
Joined
·
369 Posts
Exhaust hissing

Sounds to me like a loose joint in the exhaust. Remember, the bike is at maximum intake and exhaust at full trottle relative to the engine rpm, more throttle, more pressure. You did not say wether it was stock exhaust or aftermarket.
Most common places for a leak are the pipe to muffler joints and at the junction of the headers and head. There is a metal compession gasket at the exhast to header that should replaced every time the exhaust is removed/replaced. Some times these are hard to see, but they are there, usually copper colored.
The best way to check for an exhaust leak is to have a buddy take a thick rag and block each exhaust pipe as you listen and increase the throttle, it should hiss as the backpressure builds.
If you don't find an exhaust leak, check for intake leaks also, rubber fittings at air box to carb and carb to intake.
 

·
Registered
Joined
·
167 Posts
Discussion Starter · #3 ·
Re: Exhaust hissing

Pavogg said:
Sounds to me like a loose joint in the exhaust. Remember, the bike is at maximum intake and exhaust at full trottle relative to the engine rpm, more throttle, more pressure. You did not say wether it was stock exhaust or aftermarket.
Most common places for a leak are the pipe to muffler joints and at the junction of the headers and head. There is a metal compession gasket at the exhast to header that should replaced every time the exhaust is removed/replaced. Some times these are hard to see, but they are there, usually copper colored.
The best way to check for an exhaust leak is to have a buddy take a thick rag and block each exhaust pipe as you listen and increase the throttle, it should hiss as the backpressure builds.
If you don't find an exhaust leak, check for intake leaks also, rubber fittings at air box to carb and carb to intake.
Thanks a lot for the info. They're aftermarket pipes. I'm betting it's a leak at the head. I've had the pipes off several times without replacing the gasket, so that's likely.
 
1 - 3 of 3 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top