I have a 9 year old Associated RC10GT and have learned that these little engines run better with high quality "race" nitro fuel and when its 50F and warmer. A good quality bump starter also is a lot easier than trying to pull start it. I don't think mine ever ran when the outside temp was in the 40s.

took it the the Hobby Store today... the engine AND clutch are toast..3 weeks old. Needless to say it is going back to the mfg.

UPDATE - Bought a OFNA/PICCO .26 Big Block...should be a nice upgrade....mo power.

I forgot about pinching the fuel line. This is the KEY. NOW I remember.

Been flying models for almost 20 years now. The two that post instructions on how to tune are very good.

Just a point of reference

With ABC engines (piston uses friction to create compression not rings) you do not want to run them overly rich during break in as they will never fully break in. You need the heat in the beginning to help break it in properly for full power later.

When you have a new engine that just seems stubborn and doesn't want to run smoothly tear it apart and make sure you do not have any production junk left in the engine. Fox, K&B and Tiger where bad for this. OS and YS engines are my preferred engines.

Welcome to the hobby and sorry to hear your local shop is less than great.

Better start shopping for Kanai/ heavy duty diffs. The stock RTR ones won't last long. Also, did you upgrade the clutch?

HA! I've been flying model airplanes for 22 years!

Victory is mine.

You're right about the ABC engines though - they do need to be a bit less on the rich side when new. They are designed to be tighter at the top of the stroke to seal compression since there is no ring. When at tempurature that fit becomes a little more tolerable to operation and if they are run too cool (rich) then they won't run to full potential and they won't idle well because they are too tight and more likely just to stop.

Personally; like the big engines I prefer rings and valves (4 strokes) and only own 1 2 stroke and it's ringed as well (Super Tigre G51).

Next year will be 20 years for me so you got me by a few years. Fly mostly 4 stroke YS engines but I have a fair number of YS 61's as well.

I have 16 air planes currently. Biggest is a 14 foot j3 cub on floats.