Tao Tao ATM-50A1 - Page 3

tortoise · 10-01-2015, 03:38 AM

Quote:

Originally Posted by Astray

What are your thought on this?

tortoise · 10-01-2015, 10:12 AM

If the spark plug electrode is wet or black, as compared to beige-brown, excessive fuel may be bypassing the carb via a deficient vacuum petcock diaphragm.

Astray · 10-01-2015, 10:34 AM

The spark plug seemed to be fine when I took it out, a little darker than it probably should be but the carb is definitely running a bit rich.

Weldangrind · 10-01-2015, 11:49 AM

Adjust the valves, and then evaluate.

Astray · 10-21-2015, 04:15 PM

So I know this is really late but I basically decided to rebuild the whole engine while I was dealing with this just to make sure it wasn't compression since I was planning on doing a big bore kit (47mm bore and head) anyways with A9 performance camshaft. I also replaced the final drive gears to a 49/17 ratio on top of putting in a new performance clutch and variator. I also replaced the the CDI and ignition coil with their performance models (the blue racing CDI and orange ignition coil.) I set the valves to .003 intake and .004 exhaust but the scooter still didn't work. After checking spark I was at a loss as I hadn't considered it to be a fuel problem but lo and behold the issue was the petcock going bad. Once that was figured out I replaced it with a new manual petcock that had less chance of failure (and was also easier to see fuel flow) and the scooter started running again. Now with all these mods I just need to get the carb and variator tuned properly and I should be seeing some decent speeds after. On a flat I was only getting 43 top speed but the acceleration is pretty solid. The scooter doesn't seem to quite be getting into its ideal RPM range but I won't be able to tune it properly until I'm able to get my new tach/speedometer installed which will be saved for another weekend project.

Weldangrind · 10-22-2015, 10:56 AM

At least it's running. That's a good start.

10-01-2015, 11:49 AM	#34
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	Adjust the valves, and then evaluate. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
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10-22-2015, 10:56 AM	#36
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	At least it's running. That's a good start. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
	0

10-01-2015, 10:12 AM	#32
tortoise Join Date: Jan 2008 Posts: 221	If the spark plug electrode is wet or black, as compared to beige-brown, excessive fuel may be bypassing the carb via a deficient vacuum petcock diaphragm.
	0

10-01-2015, 10:34 AM	#33
Astray Join Date: Aug 2015 Posts: 16	The spark plug seemed to be fine when I took it out, a little darker than it probably should be but the carb is definitely running a bit rich.
	0

10-21-2015, 04:15 PM	#35
Astray Join Date: Aug 2015 Posts: 16	So I know this is really late but I basically decided to rebuild the whole engine while I was dealing with this just to make sure it wasn't compression since I was planning on doing a big bore kit (47mm bore and head) anyways with A9 performance camshaft. I also replaced the final drive gears to a 49/17 ratio on top of putting in a new performance clutch and variator. I also replaced the the CDI and ignition coil with their performance models (the blue racing CDI and orange ignition coil.) I set the valves to .003 intake and .004 exhaust but the scooter still didn't work. After checking spark I was at a loss as I hadn't considered it to be a fuel problem but lo and behold the issue was the petcock going bad. Once that was figured out I replaced it with a new manual petcock that had less chance of failure (and was also easier to see fuel flow) and the scooter started running again. Now with all these mods I just need to get the carb and variator tuned properly and I should be seeing some decent speeds after. On a flat I was only getting 43 top speed but the acceleration is pretty solid. The scooter doesn't seem to quite be getting into its ideal RPM range but I won't be able to tune it properly until I'm able to get my new tach/speedometer installed which will be saved for another weekend project.
	0