Thinking about buying a GT380. Had a couple of questions.

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ksluna
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Thinking about buying a GT380. Had a couple of questions.

Post by ksluna »

Hi guys,

I am considering buying a restored GT380. I wanted to know how it feels at highway speeds (80 mph) and more importantly, parts availability. Where I live (TX), most of the vintage Japanese bikes are Honda CBs.. I don't see a lot of Suzuki GT cycles around so I was worried about aftermarket and parts availability.

Thanks in advance.
Dave Robbo
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Re: Thinking about buying a GT380. Had a couple of questions

Post by Dave Robbo »

I've had my 550 GT around 4 months now it runs fine and is tuned correctly but speed wise its pretty flat compared to the 600 Ninja and 1000cc suzuki GSXR i had before it. However it is a 1970s bike and in its day it was competing with 1970s cars so at the time was pretty nifty. I've read a recent report on the 550 in a Classic magazine and it wasn't built for speed but good handling and smooth power out put. Now having said all of that i don't run the revs past 5000 so maybe the power band comes in after that. I realise you have a 380 and i did own one back in the late 70s but i cant remember a thing about it so would expect power to be even lower than my 550. The fuel consumption on mine at 70 is crazy so at 80 might need a fuel tanker behind.I love riding the 550 its an absolute pleasure but i'm not competing at traffic lights incase i come second.There seems to be no shortage of parts on various sites. I've recently replaced sprockets and chain and carb bellows all available within days. Im interested to hear other replies.
karl pa
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Re: Thinking about buying a GT380. Had a couple of questions

Post by karl pa »

Out of my bikes, the GT380 is one of my favorites, it is a joy to ride, but I would not like to ride it (80 mph) for to long a distance. If I remember correctly the GT380 had an issue with burning up the center cylinder, so I wouldn't try holding it at that speed for to long. The GT750 would be a better choice for those speeds.
As for parts, Suzuki still sells many parts for the 380.
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GTandcbr
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Re: Thinking about buying a GT380. Had a couple of questions

Post by GTandcbr »

IMHO The GT380 was not really made for the highway. If you are looking for a GT for there deffo go for GT750.
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ksluna
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Re: Thinking about buying a GT380. Had a couple of questions

Post by ksluna »

Hi guys, thanks for the replies! I actually don't have a GT380 and I'm close to pulling the trigger on one. It's between that and a CB550.

I do plan on riding it somewhat hard on the back roads and maybe even the occasional track day. I am just very unfamiliar with 2 strokes. I've never ridden one, or owned one. I've read they are simple, but I just don't want to get in over my head since all I've ridden are modern bikes.

I'm doing as much research as I can on 2T bikes and one thing I'm a bit confused on is this - as far as I know, you mix a proper ratio of gas and oil in 2T bikes every gas fill up. But with the GT380 or the GT series, since they are oil injected, there is no need for this and you top of the oil and change the oil like a regular 4T bike.

Also, in 2T bikes, there is gear box oil that you have to change?

Sorry if these are incredibly noob questions. I was born in the 90s lol so I don't have the experience or nostalgia of working on these bikes. I looked through the stickies and it seems like there is info on the bikes, but not 2 strokes in general. And all the 2 stroke info is on dirt bikes online!

Wondering if someone can direct me to a link or page where there is general information on how to maintain these bikes.
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tz375
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Re: Thinking about buying a GT380. Had a couple of questions

Post by tz375 »

Fortunately few 2 strokes build since about 1970 needed pre-mix. They all came with an oil injection pump - just don't forget to top it up from time to time.

Try to find old road tests for more info on what the bike was like back in the day. Here's one:

http://www.abacuscaralarms.co.uk/bikes/ ... GT380.html" onclick="window.open(this.href);return false;

the GT triples were all designed to be softer less edgy than their counterparts from Kawasaki and Yamaha, so they wre easier to live with but harder to ride really hard.

GT380 can be a fun bike if it is in good mechanical condition. If it is in poor condition or has not been run for years, the crank may need to be rebuilt with new seals which can be a bit daunting for a newcomer to 2 strokes. They can be rebuilt and many parts are available from around the world.
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Re: Thinking about buying a GT380. Had a couple of questions

Post by sportston »

If you've never owned a 2-stroke it is worth doing so. They have more character and can be more fun without being as fast as a modern superbike. Just make sure you get a good example. There are many wrecks out there. Thanks to enthusiasts there are many immaculately restored examples too. If you are not an expert, get one where someone else has done the hard work and you will find it easy to maintain
ksluna
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Re: Thinking about buying a GT380. Had a couple of questions

Post by ksluna »

sportston wrote:If you've never owned a 2-stroke it is worth doing so. They have more character and can be more fun without being as fast as a modern superbike. Just make sure you get a good example. There are many wrecks out there. Thanks to enthusiasts there are many immaculately restored examples too. If you are not an expert, get one where someone else has done the hard work and you will find it easy to maintain
the one I'm looking at is completely restored. One thing someone said is that the crank seals always go bad. Are there things to look out for (mainly things that would inevitably go bad)? I can handle maintenance but I'm not sure about owning a bike where I need to take the crank apart often.
ksluna
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Re: Thinking about buying a GT380. Had a couple of questions

Post by ksluna »

Also my riding won't mainly be highway. It will just consist of it since I live in Texas and unfortunately I have to take the highway more often than not to get to certain places. I'd say 10-20 miles at a time sometimes. Not sure if that's too much strain at 80mph on a little GT380
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Re: Thinking about buying a GT380. Had a couple of questions

Post by Zunspec4 »

Hi ksluna,

If your use leans to having a good thrash maybe the GT series is not the optimum choice for you. They can all be given a good workout but as other have intimated the GT series is more oriented towards piling on the miles at a moderate pace. All have nice flat torque curves and don't have that frantic kick in the pants as the power band kicks in. I would suggest that (sorry folks) a Yamaha RD400 (air cooled) or the RD350LC/YPVS (water cooled) would be more suited to what you want. If you want to stay Suzuki the RG500 is pretty danged fast, but affording one is another matter :D.

Cheers Geoff
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Re: Thinking about buying a GT380. Had a couple of questions

Post by karl pa »

ksluna wrote:the one I'm looking at is completely restored. One thing someone said is that the crank seals always go bad. Are there things to look out for (mainly things that would inevitably go bad)? I can handle maintenance but I'm not sure about owning a bike where I need to take the crank apart often.
If the crank seals were done when it was restored, I wouldn't worry about them. Crank seals usually cause issues when the bike sets for years and they dry out and turn hard, they can also wear out with high mileage, but I have some with 30,000 miles and still good.
I am not afraid to take my 380 on the highway for 10-20 miles at 70 mph, never really tried 80 mph, back roads is were the GT380 really is fun, and don't mind being run hard.
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ksluna
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Re: Thinking about buying a GT380. Had a couple of questions

Post by ksluna »

Zunspec4 wrote:Hi ksluna,

If your use leans to having a good thrash maybe the GT series is not the optimum choice for you. They can all be given a good workout but as other have intimated the GT series is more oriented towards piling on the miles at a moderate pace. All have nice flat torque curves and don't have that frantic kick in the pants as the power band kicks in. I would suggest that (sorry folks) a Yamaha RD400 (air cooled) or the RD350LC/YPVS (water cooled) would be more suited to what you want. If you want to stay Suzuki the RG500 is pretty danged fast, but affording one is another matter :D.

Cheers Geoff
Hm yeah I definitely planned on taking it through some back roads and expecting it to lean. Since the bike is restored the suspension is new and dialed in. I was also wanting to take it to the track. So I guess the GT series is more for touring (hence the name) rather than sharp handling, even with modern suspension, huh?
ksluna
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Re: Thinking about buying a GT380. Had a couple of questions

Post by ksluna »

karl pa wrote:
ksluna wrote:the one I'm looking at is completely restored. One thing someone said is that the crank seals always go bad. Are there things to look out for (mainly things that would inevitably go bad)? I can handle maintenance but I'm not sure about owning a bike where I need to take the crank apart often.
If the crank seals were done when it was restored, I wouldn't worry about them. Crank seals usually cause issues when the bike sets for years and they dry out and turn hard, they can also wear out with high mileage, but I have some with 30,000 miles and still good.
I am not afraid to take my 380 on the highway for 10-20 miles at 70 mph, never really tried 80 mph, back roads is were the GT380 really is fun, and don't mind being run hard.
By back road fun is that generally cruising around or would you say the bike can give a good lean with refreshed suspension? I've never ridden a vintage bike before, but I track modern bikes. The GT380 has new hagon shocks and everything is rebuilt and refreshed on the bike
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Re: Thinking about buying a GT380. Had a couple of questions

Post by Zunspec4 »

Hi ksluna,

Others might have a different view point but you are not going to experience the handling you are used to with a modern bike, especially on the track. Like all bikes of their era you will dragging the pipes around every corner with modern sticky tyres. Also they all have relatively small Dia. forks with simple damping, brakes that need a fair bit of effort, upgraded rear suspension (even Hagons) can only do so much. I still think one of the RD series would tick the boxes for you. At least a generation of additional development, reed valve induction, power exhaust valves on the YPVS etc.

Cheers Geoff
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Re: Thinking about buying a GT380. Had a couple of questions

Post by karl pa »

ksluna wrote:By back road fun is that generally cruising around or would you say the bike can give a good lean with refreshed suspension?
The GT380 can give a good lean, but I am a good bit older than you, so my lean and your lean I think might be a little different, as zunspec4 said most bikes of this era have their limitations.
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