CT are the date letters for &#
CT are the date letters for '83
Anything after 1964 runs on 50:1
There are separate adjustments for high and low speed mixtures. The high speed one is the bottom one the low speed one is the top one. If you have external knobs (It varies with serial number prefix) pull the knobs off. Gently seatthe two adjustment screws then unscrew the top one 1½ turns and the bottom one 1 turn.
The boittom one now has to be finely adjusted while running at full throttle after warming up by screwing it in a little at a time at untill it justs tends to die or spit back then slowly unscrew it up to ¼ turn to give the best running
The top one is adjusted similarly but at idle. (I was going to say in neutral but it's a fixed drive I believe but you could take the prop off!)
If necessary reduce the idle speed to as low as possible.
Refit the knobs in their mid psoitions.
I would be sensible to do a full carb clean first as there is no point in adjusting it with dirty jets!
Also clean and reset the plug first RJ6C 0.030"
