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

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

Post by ksluna »

dorT500 wrote:
ksluna wrote:Hey guys well actually it looks like there is a high chance of me buying the GT380.

Doing as much research as I can and plan on buying a service manual and finding one online.

Being new to 2 strokes, I'm just gonna dive in and learn as I go. What are things I can do to keep the bike turn-key?

As I understand, you never change the engine oil in 2T bikes, you just top off and fill up as necessary. But you do change the gearbox oil. How often do you change this? What are some things I need to look out for constantly to make sure the bike will be in constant good shape?
http://www.dansmc.com/mc_repaircourse.htm" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;"

EDIT: http://www.ozebook.com/compendium/techbuls/index.htm" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;"
sportston wrote:
ksluna wrote:Craig, is adjusting the timing a one-time procedure? Or is it treated as a maintenance item? I looked at previous threads as well as the manual linked in here and it seems a bit complex, but easy enough for a newbie mechanic like myself to do. My question is - how often would this need to be checked? Or do you all adjust it once and that's it?
Adjusting the timing on an electronic ignition system is a one-time thing. Set it and forget it.
BUT, timing on a points ignition system will always go out of adjustment as the points wear. Thus every time you adjust or replace the points you should reset the timing. On a bike with three sets of points it can be a little complicated for a first-timer to get their head around.
I would recommend upgrading to electronic ignition, if it has not already been done. It is maintenance free and more reliable and efficient
Is this a good electronic ignition? http://autocar-electrical.co.uk/product ... c/ckt-su6a" onclick="window.open(this.href);return false;

dorT500, thanks for that link. I'll be sure to read through it!
Craig380
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Re: Thinking about buying a GT380. Had a couple of questions

Post by Craig380 »

Newtronics systems are popular, there are other choices too from Europe which are just as good.

But first, I would ask the builder - looking at the video of the bike, he's done some work on the electrical system to relocate the battery, and it is not running a Suzuki factory rectifier or regulator (don't worry, this is a GOOD thing as the original Suzi charging system is a bit of a dog's breakfast, especially after 40 years) so I would not be surprised if he's already fitted an electronic ignition too.

If he HAS fitted an electonic iggy, all you would ever need to do is just check the setting one time (for your peace of mind) and then leave it alone.
1976 GT380 - wounded by me, and sold on
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed
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jabcb
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Re: Thinking about buying a GT380. Had a couple of questions

Post by jabcb »

Newtronics is a good setup. Have it my two GT750s.

Newtronics uses an external control box. Not sure were you could hide a control box on the GT380 you are looking at. So I would recommend one of the alternatives that don’t have an external control box.
Two choices that I know of:
http://www.accent-electronic.com/ELZ2Coil.html
https://classicsuzukiparts.nl/winkel/or ... e-triples/
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
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jabcb
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Re: Thinking about buying a GT380. Had a couple of questions

Post by jabcb »

The Cafe Racer magazine August/September issue has an article on the Austin Handbuilt show. A short discussion & pic of the GT380 is on page 40. A copy of the magazine would make a cool interesting addition if you buy the bike.
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: Thinking about buying a GT380. Had a couple of questions

Post by tz375 »

jabcb wrote:Newtronics is a good setup. Have it my two GT750s.

Newtronics uses an external control box. Not sure were you could hide a control box on the GT380 you are looking at. So I would recommend one of the alternatives that don’t have an external control box.
Two choices that I know of:
http://www.accent-electronic.com/ELZ2Coil.html
https://classicsuzukiparts.nl/winkel/or ... e-triples/

I have had Newtronics on a couple of bikes but I'm not a fan. Fitted an Accent to the last GT750 build and I would recommend that.

Will have to look out for that magazine. Thanks for the heads up.
ksluna
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Re: Thinking about buying a GT380. Had a couple of questions

Post by ksluna »

Hey guys sorry another oil question

I'm looking at these three engine oils

1) 100% Synthetic Ester Racing Oil for 2T
2) Synthetic 2T Engine oil
3) Semi-Synthetic 2T engine oil

I know all of these will probably work fine. I just want the absolute best oil for the engine for longevity since I intend to keep this bike forever. But I also don't want to throw money away for no reason. I don't mind spending the extra money if the synthetic is better than the semi-synth...
Craig380
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Re: Thinking about buying a GT380. Had a couple of questions

Post by Craig380 »

The ten dollar semi-synth Bel-Ray is perfect, you don't need anything else. It's a well-known brand and it meets the highest JASO and ISO standards for lubricity, detergency, low ash etc.

If you do get the bike, double-check the oil pump adjustment and make sure it is set as per the manual (it's easy to check). 2-strokes like a decent quality oil (such as the Bel-Ray you linked to), and they like a decent quantity of that oil to help keep the bearings, cylinders and pistons nice and slippery.

So for peace of mind, just make sure the pump is adjusted correctly. Once it is set, it will only need checking again if you remove the carbs or throttle cables. As said in earlier posts, it doesn't matter who worked on or built the bike - it's worth double-checking that everything's as it should be.
1976 GT380 - wounded by me, and sold on
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed
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jabcb
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Re: Thinking about buying a GT380. Had a couple of questions

Post by jabcb »

tz375 wrote:...
Will have to look out for that magazine. Thanks for the heads up.
Oops, I should have been a little more clear.

The Cafe Racer magazine discussion & info about the GT380 was not about GT380s in general, but its about the specific GT380 that ksluna is considering purchasing.
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
ksluna
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Re: Thinking about buying a GT380. Had a couple of questions

Post by ksluna »

Thanks Craig. I’ll make sure of that when I get the bike. I sent the money and will be getting it within the next couple of weeks.

I’ll also try and hunt down that magazine!


Another odd question - it’s about engine braking. In my 4 stroke motorcycles I utilized engine braking quite often whether it was coming to a stop or before dipping into a corner. I’ve read 2 strokes have virtually no engine braking? How do the Suzuki GTs feel when engine braking? Ia it almost as if it’s its neutral? I’ve also read here and there that it’s actually bad to engine brake for 2T motorcycles
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Re: Thinking about buying a GT380. Had a couple of questions

Post by ConnerVT »

2T typically have a bit less regarding engine braking. Most likely as they a lower compression ratio than their 4T counterparts. But they do slow down when you come off the throttle.

The Suzuki 2T motors are solidly designed and built. They aren't fragile little things, and hold up well as long as you don't continually flog them.

The only time to be of concern is I wouldn't leave them in a lower gear/high revs when coming down a mountain road. The oil pump has a lever which increases the fuel/oil ratio when the throttle is opened. Do riding closed throttle for several minutes while coming down a long road, at high revs, will deliver less oil to keep things lubricated. But in normal riding, no issue.
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Re: Thinking about buying a GT380. Had a couple of questions

Post by Craig380 »

ConnerVT wrote:2T typically have a bit less regarding engine braking. Most likely as they a lower compression ratio than their 4T counterparts. But they do slow down when you come off the throttle.
Although when you go from a 380 to an SV650, you quickly learn what engine braking really is :shock:
1976 GT380 - wounded by me, and sold on
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed
ksluna
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Re: Thinking about buying a GT380. Had a couple of questions

Post by ksluna »

Craig why did you sell your 380 man?!

How do you like he SV? I’ve been thinking about getting one for trackdays only
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Re: Thinking about buying a GT380. Had a couple of questions

Post by sportston »

Had a workmate with one of those. He said the 650 was under-powered and wanted to fit the 1000cc lump in it.
Had another mate with the SV1000 and he reckoned it was awesome and a bit scary.
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Re: Thinking about buying a GT380. Had a couple of questions

Post by Craig380 »

@ksluna - I'd owned the bike 17 years, had great fun on it, and loved owning it. Then on a fast ride, I holed the #1 piston (left cylinder). The bike had always had a tiny weep of oil behind the generator, which implied that seal was suspect, but it always ran great so I left it alone. I think the seal finally failed. By the the time I added up the cost of an engine rebuild (1,500 - 2,000 UKP), then the frame needed repainting, and the fuel tank could do with a refresh, and the chrome's tired .... I was looking at a complete restoration. Couldn't be bothered with doing that so I sold it as a non-runner and bought the SV.

I love the SV, it's got a great character and I think the handling and brakes (even though crude by modern standards) are great. It's light and slim and easy to get along with, and the engine is an absolute peach.

@Sportston - the SV does only produce 72bhp, which is WAY less than 4-cylinder 600cc rivals like the 600 Fazer / CBR600 etc. What the SV has is grunt, everywhere in the rev range, which makes it a great road bike. I'm no riding god, it's plenty fast enough for me.
1976 GT380 - wounded by me, and sold on
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed
sportston
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Re: Thinking about buying a GT380. Had a couple of questions

Post by sportston »

Craig380 wrote: What the SV has is grunt, everywhere in the rev range, which makes it a great road bike. I'm no riding god, it's plenty fast enough for me.
That is all you need in a bike. If you find it enjoyable to ride, it isn't necessary to have the fastest bike in town. They guy that owned the 650 I knew was a bit of a maniac, so perhaps his tastes differed from normal.
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