Starting/Idle issues

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CFS
Around the block
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Joined: Tue Nov 07, 2017 3:25 pm
Country: Portugal
Suzuki 2-Strokes: GP125, GT380

Starting/Idle issues

Post by CFS »

I finally got the 380 started after a long lay off.
The first time it stated after various attempts, it idled a little high and smoked a fair amount. After warming the motor and adjusting the idle it idled pretty smoothly on all cylinders and reved quite well still smoking more than usual.
The bike was stored whilst cosmetic works continued and re-started two days later. It started at the 3 kick and again idled and smoked as mentioned above.
Again the bike was stored whilst further cosmetic works were undertaken and re-started 3 to 4 days later. Again it started up without too much of a struggle but only fired up on the left cylinder and died. It was started up again and as before only fired up on the left cylinder, but this time I played with the throttle and managed to keep the motor running. After a minute or so the right cylinder fired up followed by the centre cylinder a minute or so later. Again it smoked more than normal.
The bike runs on a Newtronic electronic ignition, K&N pod filters has new plugs and the carbs were cleaned and set.
I have read up in this forum on the SRIS valves, and when back home, will inspect and clean them. I assume sticky/non working valves to be the culprit for the excessive smoke - any comments?
Can anyone advise on what may have been the cause for it to start as mentioned above and a possible solution/further inverstigation requirements.

As Ii work away from home on only return periodically a response from me to possible solutions/further information required may take some time.

Thanks
Carlos
sportston
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Suzuki 2-Strokes: FZ50, GP100, RG125 Gamma, GT380, Bandit 1200S

Re: Starting/Idle issues

Post by sportston »

Drain the crankcases and see if any oil comes out. There is a drain bolt beneath each crank chamber.
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Alan H
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Suzuki 2-Strokes: 4 x GT550s - J, M, A, B.
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Re: Starting/Idle issues

Post by Alan H »

Get on it and ride it for a hundred kilometers. If you keep starting it and letting it idle for a long time it WILL smoke a lot.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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ConnerVT
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Suzuki 2-Strokes: T500R (now), T500M (40 yrs ago)
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Re: Starting/Idle issues

Post by ConnerVT »

^ This

1. The fuel:oil ratio at idle needs to be significantly less than at WOT. Yes, the oil pump has a lever that helps do this, but the ratio will always be for too much oil at idle. These motors need to be run at least mid-RPM, and fully warmed, to really start to clear things out.

2. The oil check valves, even in the best, new condition, still allow for oil to leak by over time. This oil ends up in the bottom of the cylinder/crankcase. Again, these motors need to be run at least mid-RPM, and fully warmed, to really start to clear things out.
CFS
Around the block
Posts: 79
Joined: Tue Nov 07, 2017 3:25 pm
Country: Portugal
Suzuki 2-Strokes: GP125, GT380

Re: Starting/Idle issues

Post by CFS »

Thanks to all for your valued input.
I will take it out on the road when back home and report back. I know that the oil pump lever is set as per the manual but will check and clean out the valves as well.
All the replies relate to the excessive smoking and I assume that this is not the cause for the erratic starting that I experienced. Any ideas as to what may have/is causing it?
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Alan H
Moto GP
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Joined: Thu Feb 16, 2012 11:50 am
Country: England
Suzuki 2-Strokes: 4 x GT550s - J, M, A, B.
Location: The Republic of South Yorkshire

Re: Starting/Idle issues

Post by Alan H »

Residual oil in the cases.
It's all the same issue and needs a good run to clear it out.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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