Then you found the problem. Carbon build up can do this but most times running them too lean, too little or wrong oil, or simply straight gassed.
I always tune these to peak rpm and enrich to drop the rpms 50-100 rpms. It better to run a little rich than too lean. I seen too many over the years.
As for prices yes you are now using your head. It always been cost plus shipping for final cost here that gets items ordered. It can be a little strange when an Amazon vendor sells for less on Amazon then on their on website. I place an order for RX-1 and RX-2 diaphargm kits yesterday that were cheaper going through Amazon than going CTS website. Even the shipping were lower on Amazon. What was strange was that single kits were about the same as the two packs. Otherwords the two were less than the single kits which makes which kit half priced. (3.31 for two, or 1.655 ea). When I ordered 20 kits (actually 40) with shipping it was only 79.36 or 1.984 ea. which less than 3.31 ea before shipping at CTS website.
The same for my Xtreme PTO clutches I can go through Stens instead of Xtreme's website for better pricing overall. Plus I get a better shipping time when they have them in stock.
StarTech curious as to what's your tuning ballpark for us DIYers wrt the typical 33cc - 46cc home saws. I've been at it for a year now as a hobby; rebuilding some dead saws and through a lot of trial and error and help on this forum from the pros have pieced together (maybe incorrectly) that:
1. start Walbros at 1 1/4 for L H and Zamas at 2 for L H with T (throttle) screw all the way turned in.
2. tune L jet and back out T screw then back and forth until you have as little T screw as possible and idle around 2800 rpms and nice snappy trigger. Saw will run all day at 2800-2900 rpms with no surging or hunting.
3. tune H jet to 4-stroking and then (lean) turn in 1/4-1/2 or more turns to get to rich power side while in wood.
I have an el cheapo tach and found that around 11000-12000 rpms is around this range, but concerned about going too lean and burning out saw. Also don't want to be too rich and carbon up muffler either. Have searched and searched online and cannot find any manuals on WTO rpms. It's like to the info is behind the B&S Power Portal or something.
Amazing what 1/8 or 1/16 or a turn will do to rpms and the patience required (while learning) to get a perfectly good saw tuned and running.
I think it would be good to have a 2-stroke carb tuning 101 for Dummies 3 step guide for DIY stiffs like myself. Maybe if I can get enough input I'll actually start a thread on 2-stroke tuning for others to find when looking for help.