Gt380 high idle after refurb

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Fula28
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Re: Gt380 high idle after refurb

Postby Fula28 » Sun Feb 10, 2019 8:57 am

Barney rubbers are good no leaks, clamps are good tight no slipping once tight, Carbs are later with metal plate on top with , All new seals rubber boots ect. Only thing I haven't changed are shitty ole coils. Still Oem type ! I know it's low end idle issue up have read about primary coil windings being poor on 70,s coils and not firing well enough unless 1/4 throttle or above. Who knows the search continues . :roll:

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canaletto5
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Re: Gt380 high idle after refurb

Postby canaletto5 » Sun Feb 10, 2019 8:59 am

Fula28 wrote:Canaletto , can we pretension without opening cases? Again please tell me I can. Motor went together very quickly and I only had Clymer book (rubbish) . Anyways need to get it running better first . Never had so much hassle with idle circuits before .
Yes you can. I'll dig out the sequence for you

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canaletto5
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Re: Gt380 high idle after refurb

Postby canaletto5 » Sun Feb 10, 2019 9:06 am

This is a thread on fitting the 550 kick start. It is pretty much the same for the 380

viewtopic.php?f=16&t=8342&hilit=kick+starter

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Alan H
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Re: Gt380 high idle after refurb

Postby Alan H » Sun Feb 10, 2019 9:15 am

Fula28 wrote:Only thing I haven't changed are shitty ole coils. Still Oem type ! I know it's low end idle issue up have read about primary coil windings being poor on 70,s coils and not firing well enough unless 1/4 throttle or above.

New one on me that. Mind you, I've only worked on Suzy triples since 1972........
Nothing wrong with OEM coils and low tension windings are just fine. Throttle position has no relevance on coils. Pilot jets blocked are usually the culprit. Carbs have to be pristine inside, not just 'clean'. Accurate ignition timing i also an issue. If it isn't accurate it won't run right.
Proof that four strokes are over complicated

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Fula28
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Re: Gt380 high idle after refurb

Postby Fula28 » Sun Feb 10, 2019 10:32 am

So more info, carb kits are Non genuine Not keyster either another jap type kit! Float height is seemingly tricky on these, are we agreed? Do we need to set @. 30 deg,s so float tang is just touching??? So without gasket and vienier on lower gasket face I'm setting at 26mm . Another tack , the carb rubbers they are original and 1976? Suppose even with solvent sprayed around they Could be leaking but I'm not seeing any rpm differences.
Shall I just get a new set on spec? May as well at least ALl rubber would be same age then! Thanks for info guys by the way.

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Fula28
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Re: Gt380 high idle after refurb

Postby Fula28 » Sun Feb 10, 2019 10:36 am

Alan H , jets are minty clean as are fuel ways, As for timing it's on Boyer box, So should be ok I think.Not sure I can adjust the timing on that.?
Thanks for the thread on kick starter Canaletto will look at that this afternoon,once carbs are back on.

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PaulD738
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Re: Gt380 high idle after refurb

Postby PaulD738 » Sun Feb 10, 2019 11:40 am

Fula28 wrote:Alan H , jets are minty clean as are fuel ways, As for timing it's on Boyer box, So should be ok I think.Not sure I can adjust the timing on that.?
Thanks for the thread on kick starter Canaletto will look at that this afternoon,once carbs are back on.


I’m fairly sure even the Boyer ignition needs setting up. You need to align the plate that holds the triggers (where the points used to live) on the firing point marked on the rotor.
There rubbish them Jap bikes lad they won't last five minutes! you want to get yourself a nice Royal Enfield!
A quote from my old dad 8-)
1981 GSX1100 Katana Pussy Galore (the blunderbuss)
1973 T500K Dobbin (the rapier)
Seeley T500 race bike

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Alan H
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Re: Gt380 high idle after refurb

Postby Alan H » Sun Feb 10, 2019 11:44 am

With the carbs, after cleaning, you need to spray carb cleaner (via the thin tube) down ALL jets and airways and ensure there's a 'clean' spray out of the other end. Slightly spluttery or an offset spray means there's still kak in there. Modern fuel that has been allowed to go off in the carbs will leave small pieces of crap in the jets. Trust me I've been there. You might think they're clean, but.......

Never had electronic ignition on any of my bikes. Points are OK. It's not as if we need race performance is it?
Wasn't one of the Boyer cdi kits adapted from another model where the engine ran the other rotation? Not sure if that made a difference, but the timing still has to be correct or running suffers. I suppose it would affect the timing if the sensor was uncovered differently in the opposite direction?
Electronics is a funny and frustrating subject, as I found out over the last 50 years at work.
Proof that four strokes are over complicated

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Fula28
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Re: Gt380 high idle after refurb

Postby Fula28 » Sun Feb 10, 2019 12:26 pm

Thanks again , jets are all brand new and very very clean I use pro fi fuel max in the tanks of my bikes it's an aid to keep nasty ethanol and varnish at bay, So I'm 100% happy that there all clear as possible.it's just few things I need to be investigating boyer set up! And carb rubbers being hard, there soaking in isotopic and winter green oil for next couple days. Float height adjusted to 26mms without gasket too.

.Just a quick question what is the firing order on these little triples anyhoo,? Also does coil lead position matter on these? more reading required I feel.appreciate your time on this guys.

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barney01
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Re: Gt380 high idle after refurb

Postby barney01 » Sun Feb 10, 2019 4:52 pm

This may help you
https://www.google.com/url?sa=t&source= ... 9817032891
Have a look here kit 83 for Gt380 download
http://www.boyerbransden.com/instructions.html
Just one other thing. I know you are saying your pilot jets are clean and clear, but it is very difficult to inspect the internal passageways of the pilot circuit and the pilot circuit bypass. Just sayin'....


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