My Introduction - Grizzlybear

#1
I have a Forest Service cabin in Arizona. My next door neighbor sold his cabin. He was just to old and couldn't keep it up. His 3 grown boys wanted nothing to do with it. The new owner opened the shed and along with a bunch of vintage tools was a Manco Thunderbird - 3.5 HP. He gave it to me. It's been sitting for ~ 20 years. Like new except for sour gas, lots of gum, and a float that was glued in place. I have changed the old muddy oil, added fresh gas, washed it, and off I went.

It suffers from a throttle control system that is incomprehendable! It won't idle and has poor power, yet if the throttle plate is manually actuated the engine happily idles and roars when the plate is opened. That's my story. Any clever suggestions on optimizing the throttle control would be appreciated. One note; it may have been apart or tampered with. I put it back the way I found it. GB
 
#2
Welcome Grizzlybear to the great OldMiniBikes you will find a nice lace to spend some time. I suppose that 3.5 engine is a Tecumseh and I would say you need a carb rebuild.

Steve
 
#5
Thanks for the warm welcome. I thoroughly cleaned the gum formation from the carburetor and set the control needle's essentially where they were. This morning I made a few "calibrated bends" to the esoteric mechanism and it will now idle, and has more authority on the throttle plate. Will ride it later and see if I can survive. I must admit, to much go, and not enough wo, is a bad combination. Any body out there have any idea what this beauty is worth? One more thing, does anyone out there know approximate years these were made with 3.5 HP TKSY engine? Thanks in advance, GB
 
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#6
Welcome to the fun ! As per forum rules no values given , with that said you can check C.L. adds and ebay but that bike is very common and not highly sought after , although a great mini bike , keep it and ride it like you stole it !
 
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