GT380 project - new topic

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jabcb
Moto GP
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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

GT380 project - new topic

Post by jabcb »

Starting a new topic because of the Photobucket mess.

Have a GT380 mix-and-match project: 72 frame + 74 motor + 74-77 Higgspeed.

For the 74-77 models, Suzuki made changes to the frame + exhaust for more cornering clearance.
So I have the early frame, and the late motor+Higgspeeds.
Have little adapter plates to attach the exhaust to the frame. Cut the right-side centerstand bracket off so I could raise the pipes up more.

Went with wider rims & bigger tires.
Rear: stock T500 rear wheel + Avon RR 110/90-18
Front: GT550 rim + Buchanan’s spokes + Avon RR 90/90-19

Replaced the junk 300mm shocks with CLMoto 320mm shocks.

Cornering clearance with the stock sidestand is horrible.
My old topic on this is: viewtopic.php?f=2&t=12841

There was a number of reasonably easy solutions. The one I settled on uses a combo of available parts. This combo located the stand foot & tab behind where the exhaust starts to kick up.

Used an 1/2” thick aluminum spacer to lower the stand. (Edit - had the wrong spacer thickness.)
Used a T500 stand bracket that has a second set of holes drilled to move the stand closer to the center of the bike.
Used a TS250 stand with a tab created by welding on a rod.
Added few washers to the exhaust mount to move the pipe out a bit for clearance with the stand.

Pic of T500 stand bracket with second set of holes:
ImageGT380_0596 by jabcb, on Flickr

Pic of tab welded on the TS250 sidestand:
ImageGT380_0597 by jabcb, on Flickr


Pics showing the result:
ImageGT380_0599 by jabcb, on Flickr

ImageGT380_0599 by jabcb, on Flickr
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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jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: GT380 project - new topic

Post by jabcb »

GT550 4LS now installed. The old topic is: viewtopic.php?f=2&t=11181
ImageGT380_0603 by jabcb, on Flickr
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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Alan H
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Joined: Thu Feb 16, 2012 11:50 am
Country: England
Suzuki 2-Strokes: 4 x GT550s - J, M, A, B.
Location: The Republic of South Yorkshire

Re: GT380 project - new topic

Post by Alan H »

Slightly longer rear shocks will give a tad more ground clearance.
Just done a 4ls for the 550J resto. Lovely brakes when set up properly.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: GT380 project - new topic

Post by jabcb »

I also needed the longer shocks + slightly larger tire OD to get a better lean angle when on the sidestand.

I bought this one years ago for what seemed like crazy money at the time. But it was a good deal in retrospect.
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
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: GT380 project - new topic

Post by jabcb »

Done! (Except for bar end mirrors & plate)
ImageGT380_0609 by jabcb, on Flickr

ImageGT380_0610 by jabcb, on Flickr

ImageGT380_0611 by jabcb, on Flickr

ImageGT380_0613 by jabcb, on Flickr
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
Micron
On the street
Posts: 49
Joined: Thu Aug 03, 2017 1:30 pm
Country: United Kingdom
Suzuki 2-Strokes: GT 250 1975
Location: Essex, England

Re: GT380 project - new topic

Post by Micron »

That is smart, really nice :up: 8) 8)

It looks like new, well done, great job 8)
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: GT380 project - new topic

Post by jabcb »

First test run of completed project.
ImageGT380_0614 by jabcb, on Flickr
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
User avatar
Alan H
Moto GP
Posts: 3160
Joined: Thu Feb 16, 2012 11:50 am
Country: England
Suzuki 2-Strokes: 4 x GT550s - J, M, A, B.
Location: The Republic of South Yorkshire

Re: GT380 project - new topic

Post by Alan H »

Great news. How did the shakedown go?
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: GT380 project - new topic

Post by jabcb »

Didn't have time today. Will have to wait for a few days.
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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kb75ts250
On the street
Posts: 28
Joined: Tue Aug 01, 2017 11:48 am
Country: US
Suzuki 2-Strokes: ts250m
Location: Brighton, MI USA

Re: GT380 project - new topic

Post by kb75ts250 »

Great looking bike - congratulations!
Currently - 75 TS250, 02 Kaw ZX-6R
Previously - 70 T350, 71 TS250, 72 GT380, 72 TS125, 72 TS250, 75 Yam YZ360B, 72 GT380 diy cafe racer, 80 GS750, 73 TS185, 82 GS1100
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: GT380 project - new topic

Post by jabcb »

Thanks.

This was a much bigger project than I would have dared to try a few years ago.
The cumulative effect of the tips I’ve gotten from this forum over the last few years have helped a lot.
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
sportston
Expert racer
Posts: 1119
Joined: Wed Jul 10, 2013 12:04 pm
Country: England, UK
Suzuki 2-Strokes: FZ50, GP100, RG125 Gamma, GT380, Bandit 1200S

Re: GT380 project - new topic

Post by sportston »

That looks awesome! I love the fatter rear wheel and tyre. A nice tidy special bike. I'd love to hear what it sounds like with those higgspeeds. I've heard them on youtube, but the sound is very poor quality and never anything like the true reverberation of a 2-stroke in real life.
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: GT380 project - new topic

Post by jabcb »

First test ride today went well.
Just need to raise the idle & switch to an LED headlight.
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
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: GT380 project - new topic

Post by jabcb »

Upgraded to a 5-3/4” LED headlight & kept the stock headlight rim+bucket.

Used headlight ring (HL retainer) part # 35127-29610. Its used on some TS-series & small GS-series bikes like the 1980 GS450L.
Used the Rivera Primo 5-3/4” LED headlight, 1116-0201.

Pic of headlight installed in the ring. The headlight is the shallowest one I found & it wasn’t easy to get in the ring.
ImageGT380_0660 by jabcb, on Flickr

I made little adapters out of aluminum let over from the GT250 cafe project.
Adapters are 20mm wide with two centered 5mm holes. And are 31mm long with holes centered & 17mm apart.
Pic of installed adapter.
ImageGT380_0662 by jabcb, on Flickr

And installed in the GT380 rim.
ImageGT380_0663 by jabcb, on Flickr

And the result is …
ImageGT380_0664 by jabcb, on Flickr

I didn’t wire up the yellow lights yet. They can be wired up as turn signals or running lights. The GT250 cafe project has the same headlight. We had the GT250 out last night & its definitely a good upgrade over the dismal stock headlight.

The stock headlight on the 72 GT380 is part # 35121-33610. This headlight also fits some early T500/T350/T250s. I provided the details incase someone else wanted to try this upgrade.
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
User avatar
ConnerVT
Novice racer
Posts: 963
Joined: Wed Jan 18, 2012 8:01 pm
Country: USA
Suzuki 2-Strokes: T500R (now), T500M (40 yrs ago)
Location: North of Albany, NY

Re: GT380 project - new topic

Post by ConnerVT »

$200+ for a headlamp? No thanks. Too rich for my blood.
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