i don't know if i have it ALL figured out, but i do love two storkes and collecting them. i try to run older stuff native, but some of the ratios are crazy. have an old can of Piopneer oil (empty) that has the ratios on the back and there is an 8:1 ratio on it. i think that gives it just enough gas to start and burn. i am glad we have better oil now. could you imagine mowing or sawying all day to that. i love em. curse the EPA, the new 2 strokes are really amazing. the technology seems to just be starting to come into play then the EPA came into play... Rangers

Back : As GG has indicated BV-15 Mikuni Slide carbs are offered with Adjustable Main and Secondary Idle Circuit Jets also with Fix Main Jet with Variable Orifice Sized Replacement Jets . As far as the decarbonizing there are two theories of practical solution. You could try the fine water spray application during high idle to break down the crown carbon deposits or go with a chemical concentrated fuel injector cleaner & top end lubricant that either Lucas or Duralube offers , which will gradually reduce your current carbon fouling of the head and rings or in a 4-stroke application reduce carbon on Valve Train Components also . As for scratching or etching the Piston Crown gg is correct in that small scratches can develop into cracks and have potential for premature piston failure.

I realize this is a very old thread, but for the benefit of those reading reviews I thought I would share my experience. I've owned several Echo 210's. In terms of reliability the little echo is amazing. Not once in 12 years has an echo trimmer failed me in the field. I've had issues. Even broke a plastic piece on the carb that holds the throttle cable, even so I was able to put a zip tie on it and finish the day. And if I'm honest it broke due to my piling other tools in the back of the truck. Not Echos fault. The 210 is not exactly a powerhouse... Hey it's an entry level semi-pro tool. Echo should advertise them as "It just works". Year after year, use it knowing it will get the job done. In 2008 I bought a bigger Redmax trimmer. A bcz2401. Power on the Redmax was astounding, for a while. In all the years I've owned Echo, none have broken or failed under warranty. Redmax has failed in the field 5 times. Issues ranging from clogged screen to coil failure. Not once have I clogged a screen on an Echo exhaust. While it isn't hard to fix, it just shouldnt happen. Recently the Redmax failed again. It's out of warranty, but still very low hour (I've gone back to using the Echo). After this most recent failure I almost recycled the Redmax, it simply fails too often. I decided to try having it serviced by another dealer. The "new" service center recommended a carb kit, in installing it they found a defective diaphragm. Hopefully it will run as it should, but I will never have the confidence with it that I have with an Echo. Year after year, Echo just works. If it doesnt, I've yet to be disappointed by the installation of an "Echo re-power kit". It comes with everything to restore the original power (spark plug, air filter, fuel filter.) Also in 2009 I bought a Stihl fx 110. Maybe it wasnt setup properly from the dealer, others have said it should have lots more power. By the end of the first day the Stihl was in the back of the truck, my helper was using the old (6+ seasons) Echo. I probably sound like a company schill, but for my money and peace of mind, Echo is the clear winner. Btw if you regularly cut very tall or super thick grass the 230 is much torquier than the 210. It's surprising that such a small difference in cc delivers so much power. The 260 is simply a Hoss.

I have experimented related to your concern. I needed to stand straighter vs bending and have a good reach (due to back issues) with a lighter trimmer. I found the following to be challenges but not real issues. It all came to me from servicing and owning 8-10 donated trimmers. Many donated working or after small repairs. I donate as working or parts to Yardmen that saved used parts. These Echo Power Heads can be challenging, time consuming (from lack of maintenance). All have worked well w/o any locked so far. Such as, an Echo HCA 2400 Power Head was on an Extended Hedge Trimmer that laid openly on the ground over a year. It runs well “directly on a string trimmer”. A killer PE-200 was given to me after starting easy and only idling. I finally got the carb repaired/adjusted as I promised the donator it needed (w/o spending a penny vs left over parts is “OR” Was My Killer). My 03 retirement is slowing on Donations And Volunteering, LOL! 1. My best powers were commercial grades engines with solid steel drive shafts and heavier power heads in some cases. 2. With a collection of trimmers (various brands) I started to mix & Match (WITH CAUTIONS) with Echo SRM mid grade engines (that had proven in 10 yrs of use to be a good power heads). 3. My goal was to use my Echo SRM 210 that has worked since 2000 w/o any problems. It was a straight shaft with a cable and string. It’s now a straight shaft and hard blade. The idea and hard blade head came from my Commercial Green Machine and “no more bending”. 4. I also wanted to keep a straight shaft with a string and did with an Echo HCA power head. 5. I also added a split straight shaft (for string/hard blade attachments) to an Echo PE-2000 Power Head.