Tank 150 starting issues

[portero72]

Howdy all. The gf has a Tank Urban Classic 150 that sat unused for a year or more(and whose reliability was suspect prior to that). Dove into the carb, thinking it needed cleaning, which it did, but still would not start. Replaced the carb with a new one, fired right up and ran for a cpl weeks, then returned to cranking but not running. On a whim, I bought ANOTHER carb and swapped it. After a bit of cranking, it fired up and ran great for about 2 rides. Now it is back to cranking but not turning over. I have confirmed spark is good and fuel is flowing. So, TWICE it has responded temporarily to a new carb, only to die within a few rides. Any pointers on where to look to get this heap running?

[blueboy5000]

Adjust the valves to .004" intake and .005" exhaust.

[rks]

How about the rest of the fuel system? Have you removed, drained, cleaned, the tank? Have the rubber fuel lines been replaced with a tygon type? Ethanol blended fuel will destroy rubber lines from the inside out.....the exterior may look fine, while the inside is being eaten up, causing problems further along the fuel system.

After everything is clean.....you might think about using something like Marvel Mystery Oil on a regular basis. I add .4 ounces (4/10ths of an ounce) at every fuel up. Last year this cost me $1.98 to treat the 35.4 gallons of fuel I used to go 3,159 miles. Scooter is just over 4 years old, and has just over 9,200 miles on it, never have had a starting or running problem....and I have never cleaned the carb.

[portero72]

Adjust the valves to .004" intake and .005" exhaust.



Valves. Not the first time I have heard that. I have done valves on my dirtbike before, I assume it isn't terribly complicated?