Hi simba350

I have been running Techwell motors both the pull start,3 port and 5 port open versions,for about 18 months now and have found that they always tend to be sluggish at the bottom end.
I have found that removing the head shim tends to reduce this sluggishness. Also if running a power clutch wind it in more which allows the motor to pick up before engaging.
I have found that running an no.8 plug is the best for the Techwell however this may vary depending on air temp and humidity.
In regards to bottom end mixture setting I have found that you are better running it on the richer side than lean.
With the fuel I also run 16% nitro but make sure you run somewhere around 10-11 % oil any more and this also affects performance.
However I have never totally got the bottom end right.I beleive this may be a continuous problem with the Techwells.
If you do sort it out let me know.