Thought I seized my motor!

[jk50]

It’s kind of cold out (40f) my second buddy 50 had only 2 miles on it. I knew it needed warming up. Idled for a minute, rode gently for 2 minutes or so. Up small hill, then down, riding pretty slow.. the coasting down the hip might have been a problem. Came to a stop sign, accelerated, then the engine seemed to just seize. Seemed like smoke from the exhaust. Oh no! Did I just seize a new engine!? Looked it over, seen there was oil in the pump suction line. Cranked fine, started, rode again. Happened a second time decel enfije died. Restarted and rode home. Cooled it down, started and rode around a mile or so. Ran fine.
I’m not exactly sure what happened. I did drain the oil tank and refill, running some caned fuel. I added an ounce of oil to the gas when I got back maybe it needed a little extra for break in, or maybe there was an air pocket in the oil line? Hopefully it’s fine now. Cold seizure was a concern it was cold out. Restarted fine. Two strokes can be sensitive.

[az_slynch]

Did you happen to check the ring gap when putting the new cylinder on? It should be about .004" for each inch of bore, so if it's a 46mm big bore, you want .007" of ring gap, possibly .008" if wish to regularly run at or near WOT.

It's also a good idea to add a bit of oil to the fuel tank (~1% mix) when breaking in a new cylinder. Some manufacturers recommend doing this this for the first ~200 miles or three tankfuls.

[jk50]

oh, no. this is another buddy 50, a new, but older one. The 70cc kit one is still being put back together. I did pull the plug, to me it looks on the lean side of good? oil mix is good with slight signs on the threads? its completely stock but it is de restricted.

[jk50]

on the 70cc kit one. I think I'll add another ounce of oil to the tank already added .5oz. that would bring it to 1% or, 100:1

[az_slynch]

Yes, that plug looks to be on the lean side. You want the center ceramic insulator to be taking on a caramel color.

[jk50]

Well, the photo makes it a little whiter but, yeah it’s definitely EPA lean. I do wonder if I starved the engine of oil a bit. I didn’t think there would be air in the line because I didn’t take it off the pump end, and there was still oil in the filter, I also didn’t bleed it. Oh well, it seems ok so far. Took it a few more miles today.
On another note. The plastic fan shrouds are much more difficult than I imagined. Sure, one can just bolt them down but, to clip them together, figuring out what side the upper end of the inner shroud goes. Took forever. Especially because I noticed the new scooter’s shroud wasn’t quite right ether.

[jk50]

Took it out for a few more miles today, still good. I found the scooter was exhaust de restricted but, varriator restricted, took out the spacer, much better. Even if one is still only going 30-35mph the RPMS are much lower at that speed with the spacer removed.