gt550 pipe broken inside

[carlo]

Hej
In front of one of the pipes there is a breakage. The part here has a movement when i shake the pipe. When I drive, it sometimes sounds like beat of a hammer, specially when i take off the gas. Can I do anything to fix it? Cut up inside, and try to fasten it, or is a new one the consekvens?
Thanks for answer

[oldjapanesebikes]

Hej
In front of one of the pipes there is a breakage. The part here has a movement when i shake the pipe. When I drive, it sometimes sounds like beat of a hammer, specially when i take off the gas. Can I do anything to fix it? Cut up inside, and try to fasten it, or is a new one the consekvens?
Thanks for answer

Based on your description, it sounds like a loose internal baffle plate, which is not uncommon. If that is the problem, then the most cost effective option would be to replace the pipe. It could also be part of the removable baffle that has broken off and been left inside the pipe in which case you could choose to just leave it be. If you have access to a fibre optic inspection camera you can tell for certain which it is (do you know someone at a friendly local auto repair shop possibly ?) and then decide which course of action you want to take.

[carlo]

Sorry,I did not get say, that i had taken the removable baffles out, for cleaning.They was all ok. I think about, that I could have spoiled something in front of the removeable baffle by screwing, to get it free. I'm not sure, there was something wrong before I disconnected and was on the road. I had just been owner a short time.

[oldjapanesebikes]

A previous owner could have replaced the removable baffle eh ? But it usually is a loose or broken baffle plate that causes the rattle - they are spot welded and will pull away if the removable baffle has been jammed or rusted in.

[tz375]

Inside the muffler are a series of round plates which are spot welded only to the inner half shell of the muffler. Here's one that was split open and has a baffle in place.



The plates vibrate and crack and when the baffle tube is removed, they fall down and make it hard to refit the baffle tube. You can probably insert a length of straight tube to juggle the plate back into place and then replace the baffle carefully. If you have the exhaust off, it's possible to see the spot welds on the inner surface (facing the wheel). There are a lot of welds there for the inner sounds absorbing pads as well as the baffle retaining plates.


See the spot weld indentations where the plates support the baffles? There are 6-8 spot welds on each.

You may be able to drill the inner half of the muffler shell at the right spot and weld the plate back into place or retain it with a self tapping screw. If the plate has broken up and not just come loose, it's not so simple to repair.

[carlo]

Thanks a lot, very useful for me

[pearljam724]

Good excuse to now plunge for those expansion chambers you always wanted.

[carlo]

What changes are necessary on the bike, after mounting expansion chambers? How much power will be the prize, and will the engine be more weak for repair? How much to spend for the chambers?

[pearljam724]

What changes are necessary on the bike, after mounting expansion chambers? How much power will be the prize, and will the engine be more weak for repair? How much to spend for the chambers?

No changes necessary, other than changing your main jets to larger ones. That's cheap, fast and easy. Don't expect a whopping horsepower gain. Other than a few to several horsepower on the high end of the rpm range. The greatest benefit is weight reduction. Expect to lose close to thirty pounds. That translates into better exceleration and it being a little more nimble. 30 pounds is huge in the bike world. Gt stock exhaust are rediculous in how much the whole system weighs. The engine does not lose any reliability if the carbs are retuned with the new jets. A lesser quality set as far as aesthetics can be
bought in the states for close to 700. Where a very nice set of stainless can be found overseas for close to a grand. Combined with a gearing change. The bike will be vastly improved.

[carlo]

Thanks a lot for info.