The Suzuki GT380

Under the radar

SuzukiGT380

Back in 1972, the Suzuki GT380 was one of a handful of two-strokes sitting on the sales floor at your local Suzuki dealership.

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Suzuki GT380
Years produced:
1972-1977
Total production: N/A
Claimed power: 38hp @ 7,500rpm (claimed)
Top speed: 95mph
Engine type: 371cc, air-cooled two-stroke inline triple
Transmission: Six-speed
Weight (w/half-full tank): 178kg (392lb)
MPG: 32-46
Price then: $925 (1972)
Price now: $900-$2,000

Remember back when you could still buy a brand new, out of the crate, street-legal two-stroke motorcycle? Those were the days … Nixon was president, Vietnam was a raging mess, and … wait. What was so great about those days again? Ah, yes. The motorcycles.

Although two-stroke engines are rare in new motorcycles today, back in 1972 the Suzuki GT380 was one of a handful of two-strokes sitting on the sales floor at your local Suzuki dealership. The younger sibling of Suzuki’s landmark water-cooled GT750 “Water Buffalo” (introduced in 1971), the three-cylinder GT380 Sebring was introduced to the U.S. market in 1972 along with the bigger GT550. The GT380 landed right in the middle of the 350cc-400cc field, one of the most hotly contested displacement categories of the day.

Sporty, but not sportingThe original 1972 Sebring arrived as a fairly sporty motorcycle, but only to a point. Though the competing Kawasaki triples were known as rockets, the Suzuki GT engines were tuned more for smoothness and reliability than peak power. The odd three-into-four pipes and the rigid foot pegs limited cornering clearance, and while predictable, comfortable and smooth at touring speeds, when pushed hard it wobbled in corners due to its limited suspension and a tube frame that could have been stiffer. This was not a track bike.

The air-cooled GTs shared Suzuki's new Ram Air System, which forced cool air to pass through the cylinders and behind the block when the bike was in motion, preventing the engine from losing power due to high cylinder head temps. Unfortunately, the GT triples still developed a reputation for seizing their middle pistons.

The GTs also featured Suzuki’s refined automatic fuel and oil mixing system, called CCI, which helped lower exhaust smoke levels. The GTs also were the first in the Suzuki line to feature vacuum-operated petcocks, a feature that was later used on all of Suzuki’s bikes.

The Suzuki GT380 was blessed with a large gas tank and a large seat, though engine vibrations transmitted through the passenger footpegs made the bike less than fun for passengers. The little GT also featured a locking gas cap (unusual at the time) and rubber lip seals on the spark plug wire caps to keep moisture from shorting out the system. Though the cylinder head was cast in one piece, the cylinders were three separate units.

Through the yearsThe Suzuki GT380 received some small improvements over the years of production. For 1973, the GT380K came with a 275mm disc at the front in place of the drum brake used on earlier models. It was an improvement over the drum, but only if it was dry: It was hopeless in the wet. A few small changes were also made to the frame and exhaust system to provide a bit more ground clearance and reduce vibration. The 1974 GT380L had constant-velocity carbs, an available cooling fan, and the final drive sprockets were changed to raise the gearing. The bike now also featured a gear indicator. The 1975 GT380M saw the carburetors revert to the slide type, while the 1976 GT380A model stayed essentially the same, other than evolutionary paint color changes that happened throughout the bikes’ tenure. The end of the line came with the GT380B in 1977, which can be easily identified for it’s black (instead of color-matching) sidecovers.

In truth, the models between 1975 and 1977 look a lot like each other, with only minor color or accessory options separating them visually.

In the end, although the little GT was as strong and reliable as similarly displaced four-stroke machines, the rising gas prices of the Seventies and the higher fuel consumption of most two-strokes didn’t make for the best pairing. Add to that the introduction of Suzuki’s four-stroke GS series in 1976, and many buyers wondered why they should deal with gas-guzzling, smoking two-strokes if they didn’t have to. Many simply decided they didn’t want to anymore, and when Suzuki's new 1978 models arrived, the small triple was gone, along with the rest of its GT siblings.

Though the bigger GT750s have had quite a following since they were new, the 380 has been forgotten by most people. That, and the fact that quite a few were made and imported to the U.S., has kept prices low.

 
christian
1/22/2016 12:49:49 PM

With great excitement I bought my first bike in 1973 which happened to be a blue 380 GT Suzuki. I remember my father going guarantor for me to get a loan from Custom Credit for $970 - boy what a debt that was!!! My father was disgusted. He also felt I should be buying a cheaper second hand bike- not the shiniest bike in the Newcastle showroom. I remember riding the bike back home through Newcastle traffic with my heart in my mouth and with great trepidation. I had it equipped with back and front crash bars just to be safe and in its lifetime I never once dropped the bike. I also remember fixing red reflective tape all over the bike. I was a real poser! The bike brought me much joy, as a commuter to uni daily and for longer trips to Qld etc. When it was running well it was as smooth as silk but I had a few dark moments when the centre plug continually oiled up or I scraped the centre stand or foot pegs. It also tended to wobble a bit with the not- so-rigid frame. But I really enjoyed the Suzi. Now I ride a Kawasaki W800- a vastly superior bike- but we are living in the 21st century.


ricohelmero
8/4/2015 3:39:56 PM

Sorry for the typo. I didn't proof-read. Should read buddy not bubby.


ricohelmero
8/4/2015 3:29:23 PM

I purchased a GT 380 new in 1973.I put 7500 miles on that summer with the highlight being a trip out east to the Cabot trail.My bubby had the GT 550 ( swine!) and we cruised all day @ 70 mph.All we did was add injector oil and fuel.I did however crack the center piston when it overheated coming back from work...stop & go traffic.Otherwise,an excellent machine,especially for it's displacement.Felt like I was on a cruiser.


steven cote
7/13/2013 5:54:34 PM

I bought a left over 75 in 76 for my first bike, my parents where not very happy about it, I think i paid $1100 for it, I really wanted the Honda Cb400 4 but that cost a lot more. I remember it being very smooth, lousy mileage (gas was cheap back then still under a buck) and every thing ground when a corner was taken at some speed. I put 9k on it in one year and I never really went anywhere, just riding around. I sold it in 1977 for a 77 XS650 mileage went way up but so did the vibration. I'm not sure if I would buy one if one came up for sale but I would love to ride one to see if it would make me feel like I'm 19 again.


chris painter
6/24/2011 9:34:23 AM

Originally started riding in 1975 on a Suzuki 250 with the old Ram air system after which i had 2 gt380's and a gt550, in all the time i had them never had a breakdown they were reliable, fun and smooth as silk, even today i still haven't come across anything to really beat them for that, yes fuel consumation could be bad with the throttle wide open, but the howl from the exhausts was great, thinking back i wish i'd kept one, I would be the first in line to buy one if they ever reintroduced them, which they unfortunately wont!!!!


donald thorp
5/22/2011 2:15:33 AM

I bought one of the first 1972 GT380s to arrive in Dallas Texas. I enjoyed riding it because of it's enjoyable ride and power. I could usually beat any other 350 even with a passenger. I traveled back and forth from San Antonio to Dallas on this bike many times while in the Air Force. The only problem I ever had was that the center exhaust studs worked loss alot. I've been riding bikes since 1966 and still ride. I have always felt that the GT380 was one of my best purchases and regret selling it.


kevin_3
8/13/2010 10:00:38 AM

Hi Gerry, I also have been a spanner for 25 years, and have never seen one seize its center piston, but I do know where the myth comes from, early on, a few of the new owners not putting any 2 stroke oil(not even knowing there was a tank for it) seized their machines, and without oil, the center cylinder was often the first to go, and over the years, and with Chinese whispers, it turned into GT's having weak center cylinders.


gerry grafstrom_2
2/25/2010 8:34:54 PM

I don't know where you got your information, but I have worked on Suzukis since 1974 and worked as a Suzuki service rep from 1981-1996. I have owned a GT250K, GT380M, GT550A, and GT750K. I have never seen a GT seize its center piston. I'm also fairly certain the GT380 carburetors remained pretty much unchanged from 1973-1976. They were a great motorcycle and rivaled the four strokes of their day for reliability. Gas mileage was lower, but performance was higher. They were a nice compromise between the performance but unreliability of the Kawasakis and the reliability but deadly boredom of the Hondas.