info on GT750 expansion chambers

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jabcb
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
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info on GT750 expansion chambers

Post by jabcb »

Anyone know anything about the GT750 expansion chambers shown in the pic?
GT750chambers1.jpg
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BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
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tz375
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Re: info on GT750 expansion chambers

Post by tz375 »

Pretty sure that they are J&R, though the end of the muffler looks longer than any I have seen before, so it is possible that the baffles have been modified or replaced.

Do you have a picture of the baffles and where the chamber joins the header?
Craig380
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Re: info on GT750 expansion chambers

Post by Craig380 »

+1 to what Richard said, the mounting plate is typical J&R, as is the relatively slim diameter of the pipes. Looks sweet with the GS wheels :up:
1976 GT380 - wounded by me, and sold on
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
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jabcb
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Joined: Mon Dec 13, 2010 4:32 pm
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: info on GT750 expansion chambers

Post by jabcb »

Bike is in storage & have no baffle pic.
Header pic:
gt750_header.jpeg
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BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
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tz375
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Location: Illinois

Re: info on GT750 expansion chambers

Post by tz375 »

That looks like a J&R pipe. The header is shorter than usual though and that first bend at the clamp section is about 2 inches further forwards than normal and the pipe is closer to the motor.

When it comes out of storage, maybe you can measure the pipe and I can compare it to a set of J&R pipes in the shop here.
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jabcb
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Joined: Mon Dec 13, 2010 4:32 pm
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: info on GT750 expansion chambers

Post by jabcb »

Two more pics. That's all I have till spring.
gt750_header6.jpeg
gt750_header7.jpeg
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BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
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tz375
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Joined: Mon Nov 03, 2008 10:47 am
Location: Illinois

Re: info on GT750 expansion chambers

Post by tz375 »

This mystery will have to wait until spring I guess. Do you happen to have removed the pipes or do you know if the headers have threaded collars ie stock headers?
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jabcb
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Posts: 4311
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: info on GT750 expansion chambers

Post by jabcb »

Answers will have to wait till spring -- I haven't seen the pipes removed.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
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