GT380 Ticking noise

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bugrump
Still in the Driveway
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Country: United Kingdom
Suzuki 2-Strokes: 1976 GT380

GT380 Ticking noise

Post by bugrump »

Hi Guys
new to the forum as I recently managed to afford the purchase of my first ever bike a 1976 Suzuki GT380, had to pay a bit more than I bought my first one for (£769 on the road).
The problem is I'm getting a tinny ticking/rattle around the points kick start area (can't seem to pin it down exactly), the noise disappears when she's revved. Since buying her I've replaced the pistons and rings/ checked the bores and bearings/ fitted electronic ignition, any ideas guys it's driving me nuts
cheers
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grumps
Around the block
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Suzuki 2-Strokes: GT 380, 1977 (now sold)
Location: Worcestershire

Re: GT380 Ticking noise

Post by grumps »

Sorry, can't help with the query, but welcome anyway.
If money can't buy happiness - explain motorcycles and beer!
GTandcbr
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Suzuki 2-Strokes: suzuki gt 550j
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Re: GT380 Ticking noise

Post by GTandcbr »

Welcome to the forum. What sort of electronic ignition have you fitted? I had a similar problem which turned out to be the screws holding the lampholders were too long and the timing windmill was clipping them.
98 carb Blackbird and GT550j
bugrump
Still in the Driveway
Posts: 4
Joined: Sun May 31, 2020 7:13 am
Country: United Kingdom
Suzuki 2-Strokes: 1976 GT380

Re: GT380 Ticking noise

Post by bugrump »

Thanks for the responses guys, should have mentioned the electronic ignition system is made by NewTronic.
Don't know if that's the cause but the screws don't seem to be too long!
sportston
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Suzuki 2-Strokes: FZ50, GP100, RG125 Gamma, GT380, Bandit 1200S

Re: GT380 Ticking noise

Post by sportston »

Welcome! I came across that on a GT250 with Newtronic ignition. In that case the spinning interrupter was just catching the sensors. It was due to a poorly engineered base-plate that didn't quite put the sensors in the right place and a badly formed interrupter. One sensor was fine, but the other was not. It damaged the sensor because it scratched the lens. It was an old system of very poor quality. I am told the new systems are better but I have not had any experience of that. I put an Accent system on my own GT380. Starts first kick and very easy to install. Haven't done many miles on it yet though.
There are other things that your ticking noise could be. Something loose inside the clutch cover perhaps. One of the tiny screws for holding plates on might be loose.
Other possible ticking noises:-
Rev counter cable not correctly seated or worn internally
Loose spark plug
Cross-threaded and poorly seated spark plug
HT arcing on either plug lead or plug cap (sometimes inside the plug cap and invisible)
Poorly sealed head gasket
Incorrect spark plug fitted (yes, really. Came across that once before when the owner had fitted plugs that were slightly too long and where just being kissed by the piston)
Exhaust gasket leak
Damaged piston ring
Piston hitting cylinder head (can be due to excessive skimming of head or barrel, incorrect piston or incorrect gaskets)
Piston hitting head gasket (due to incorrect gasket diameter)
Excess play on small end (did you fit new bearings when replacing the pistons?)
Unseated gudgeon pin clip

All the above can make varying types of ticking noises, though it isn't an exhaustive list. I'd start checking the easy things first. Check the ignition system is not catching or loose first. If that is ok, then disconnect the rev counter cable from the top of the gearbox and see if the noise disappears and so on...
Good luck
Tom
bugrump
Still in the Driveway
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Joined: Sun May 31, 2020 7:13 am
Country: United Kingdom
Suzuki 2-Strokes: 1976 GT380

Re: GT380 Ticking noise

Post by bugrump »

Wow! Cheers Tom for the weekend work! No only joking.
Looks like I've got a lot to be checking, although it doesn't surprise me given the previous owner was a supposed expert on two strokes (heavy pinch of salt). The poorly fitted café racer seat (now an original) and the aftermarket wing mirrors (also rectified) gave me a bit of a clue, can't complain given the price I paid.
Thanks for the help and I'll keep you updated on progress, have a great weekend.
Cheers
Craig380
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Re: GT380 Ticking noise

Post by Craig380 »

It could also be something ratting in the right-hand exhaust. The body of the pipe has a sound-absorbing mesh spot-welded inside at the factory, and after a few decades it can break loose. Also the main baffle plates can get loose and rattle. Ask me how I know this :wink: :D
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
bugrump
Still in the Driveway
Posts: 4
Joined: Sun May 31, 2020 7:13 am
Country: United Kingdom
Suzuki 2-Strokes: 1976 GT380

Re: GT380 Ticking noise

Post by bugrump »

Cheers Craig, I'm still working on Tom's list but I'll definitely check it out. Doing the straight forward checks first before having to resort to a tear down.
sportston
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Suzuki 2-Strokes: FZ50, GP100, RG125 Gamma, GT380, Bandit 1200S

Re: GT380 Ticking noise

Post by sportston »

Craig380 wrote:It could also be something ratting in the right-hand exhaust. The body of the pipe has a sound-absorbing mesh spot-welded inside at the factory, and after a few decades it can break loose. Also the main baffle plates can get loose and rattle. Ask me how I know this :wink: :D
Yes good one. I forgot that.
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