GT380 condensers.

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Glyn.G
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Suzuki 2-Strokes: Suzuki GT380 B- Yamaha FZ1
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GT380 condensers.

Post by Glyn.G »

Hi all,
Out for a ride recently on my GT380 when I suddenly got a problem with the idle speed. I pulled up at the lights and the engine just faded and died and would not fire up again unless I put the choke on then it started straight away. Engine would only idle at revs above 1500rpm anything lower and it just died. So I headed home and on the way I started to get a misfire. My immediate thought was blocked idle circuit in the carbs so I stripped and cleaned them but no difference. I then took off the points cover and started her up and it looked like someone had lit a firework in there, the points were sparking like a Roman candle. Again idle speed dropped and died. I know the points shouldn't spark from reading previous posts, but would this cause the problem I have. I have only done about 2000 miles on a set of new condensers and it looks like they're knackered already and all the sellers on e-bay and Discount Bike Spares seem to be offering the same exact make. Can anyone offer a different make & seller for new condensers that may last a bit longer.
Again as I'm not sure, could the sparking points cause this idling and misfire problem ? Oh I forgot to say that the bike runs better in the higher rev range.
Many Regards,
Glyn.
Craig380
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Re: GT380 condensers.

Post by Craig380 »

It's possible that dodgy condensors could do that, you certainly shouldn't be seeing big sparks at the points. Small ones, yes, but not big.

When I got my 380 in 1998 I fitted Daichi brand condensors from Crooks Suzuki, and they were still on the bike when I sold it, they never failed.
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jabcb
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Re: GT380 condensers.

Post by jabcb »

The stock sparkplug caps have resistors in them that can go bad. Perhaps this is causing it to spark more at the points than it should, and less at the plugs than you need.
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Vintageman
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Re: GT380 condensers.

Post by Vintageman »

Aftermarket condensers don't last. OEM way to go. Denso still available. Kokusan obsolete 33263-33020 on ebay right now.

They burn fast and higher speed will go miss pop and bang out pipes. If only issue at low rpm, low battery?
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Glyn.G
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Joined: Fri May 30, 2014 5:41 am
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Suzuki 2-Strokes: Suzuki GT380 B- Yamaha FZ1
Location: High Peak Derbyshire.

Re: GT380 condensers.

Post by Glyn.G »

Hi,
Thanks for your replies, I have now ordered some non-resistor plug caps but I can't find a supplier of the Denso condensers ( 33261-33010 ). Can any one point me in the right direction of a supplier in Blighty. I forgot to mention in my previous post that the engine does misfire at higher revs when riding the bike but it managed to get me home.
Again thanks for all your help, I would be lost without it.
Many Regards.
Glyn.
fredvincent
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Re: GT380 condensers.

Post by fredvincent »

Hi Glynn,
I always use Robinsons Suzuki Parts Finder - I have just checked and they have both types of condensors in stock.
Good luck, Roger
Glyn.G
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Suzuki 2-Strokes: Suzuki GT380 B- Yamaha FZ1
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Re: GT380 condensers.

Post by Glyn.G »

Quick update,
Just fitted a new set of condensers from Discount Bike Spares (same as the ones that were on Daiichi ). Misfire has gone with no sparking at points, well very little. Accelerates good right up to the red line and feels a lot smoother engine wise but the idle problem is still there. Anything below 1500 rpm and the engine just fades and dies and will not start up again unless the choke is applied. I'm beginning to think of carb idle circuit again but I'm sure I cleaned everything last time. The funny thing is if I turn the engine of with the key like at the petrol station it fires straight back up again without choke but the idle problem is still there.
Totally Baffled now,
Glyn.
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Suzsmokeyallan
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Re: GT380 condensers.

Post by Suzsmokeyallan »

While you have the carbs off,,, again, perform a leak down test on the cylinders to make sure the crank seals are good.
Two strokes, its just that simple.

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ConnerVT
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Re: GT380 condensers.

Post by ConnerVT »

Have you checked your battery?
Glyn.G
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Suzuki 2-Strokes: Suzuki GT380 B- Yamaha FZ1
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Re: GT380 condensers.

Post by Glyn.G »

ConnerVT wrote:Have you checked your battery?
Yes battery is good and fully charged.
Glyn.G
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Joined: Fri May 30, 2014 5:41 am
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Suzuki 2-Strokes: Suzuki GT380 B- Yamaha FZ1
Location: High Peak Derbyshire.

Re: GT380 condensers.

Post by Glyn.G »

Update,
Well it looks like the problem may be solved. I put my spare set of carbs on and hey presto, got a nice even idle speed of 1100 revs with no fading and dying problem. Not had a chance to try it on a run yet but fingers crossed. Looks like it was muck in the carbs after all but how did it get in there. The carbs were cleaned thoroughly in my sonic cleaner and I have an inline filter on.
At least the problem got me to sort out other niggling faults I had ( sparking points ).
I wonder if there will ever come a time when these little faults will stop and I can be confident to just start it up and enjoy the ride as it's great fun.
Many Regards,
Glyn. :D
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