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@toalmar avatar
UTC

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GTS 300
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@toalmar avatar
GTS 300
Joined: UTC
Posts: 39
UTC quote
When I bought this 300 GTS it didn't start. a couple of people had bought it like this but didn't get it start. Last owner had tried lot of thinks, and he had a similar scooter and swapped parts to check. I am not sure but he could maybe also have adjusted the screw to adjust the throttle butterfly.
When I got the scooter I checked several things and I found the register chain to be a couple of teeth wrong. When I made it right it started at once.

But I have some issues still with it.
When startup when cold (8-10 degree) I start at once but at low rpm, and when I raid the rpm it almost stops. When engine has got some heat it is better, but still I feel the rpm is to low.

So to my questions:
1. If this screw has been adjusted in or out what will happen?
2. If I try to turn it 1/4 or 1/2 turn in or out will that make it better if it has been turned earlier?
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⚠️ Last edited by Toalmar on UTC; edited 1 time
@jimc avatar
UTC

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The Hornet (GT200, aka Love Bug) and 'Dimples' - a GTS 300
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Posts: 43907
Location: Pleasant Hill, CA
 
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@jimc avatar
The Hornet (GT200, aka Love Bug) and 'Dimples' - a GTS 300
Joined: UTC
Posts: 43907
Location: Pleasant Hill, CA
UTC quote
I do hope that hasn't been adjusted! Just like the TPS (throttle position sensor setting) it should only be touched at the factory.

Assuming all the more common maintenance checks have been done - air filter, throttle body idle bypass, no cracks in the intake manifold, injector spray pattern good - the next thing I'd do would be adjust the valve clearances. This can easily cause the 'near stalling' symptom when cold.
OP
@toalmar avatar
UTC

Member
GTS 300
Joined: UTC
Posts: 39
 
Member
@toalmar avatar
GTS 300
Joined: UTC
Posts: 39
UTC quote
jimc wrote:
I do hope that hasn't been adjusted! Just like the TPS (throttle position sensor setting) it should only be touched at the factory.

Assuming all the more common maintenance checks have been done - air filter, throttle body idle bypass, no cracks in the intake manifold, injector spray pattern good - the next thing I'd do would be adjust the valve clearances. This can easily cause the 'near stalling' symptom when cold.
First of all, thanks for the informative feedback
Most of the common maintenance is done.
- Air filter been checked, cleaned and sprayed with filter spray
- Injector spray pattern looks good, checked before I got it to start
- Valve clearance checked and adjusted when I moved the register chain to right place

So I will check the Throttle body idle bypass, and the cracks in the intake manifold. Need to get some cleaner for it.
Any tip for right type?
@jimc avatar
UTC

Moderaptor
The Hornet (GT200, aka Love Bug) and 'Dimples' - a GTS 300
Joined: UTC
Posts: 43907
Location: Pleasant Hill, CA
 
Moderaptor
@jimc avatar
The Hornet (GT200, aka Love Bug) and 'Dimples' - a GTS 300
Joined: UTC
Posts: 43907
Location: Pleasant Hill, CA
UTC quote
Toalmar wrote:
First of all, thanks for the informative feedback
Most of the common maintenance is done.
- Air filter been checked, cleaned and sprayed with filter spray
- Injector spray pattern looks good, checked before I got it to start
- Valve clearance checked and adjusted when I moved the register chain to right place

So I will check the Throttle body idle bypass, and the cracks in the intake manifold. Need to get some cleaner for it.
Any tip for right type?
I just use ordinary carb cleaner.
OP
@toalmar avatar
UTC

Member
GTS 300
Joined: UTC
Posts: 39
 
Member
@toalmar avatar
GTS 300
Joined: UTC
Posts: 39
UTC quote
I buyed Carb cleaner today and sprayed into throttle body.
The scooter is now working like normal.

Thanks for the help guys
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