Piston Skirt

621SX is an updated version of 620SX. Added few external durability improvements like starter metal inserts, metric threaded crankcase screws, updated roller catcher. New clutch cover has captive nuts (same as 7310). Internally - engine has slightly more low end torque and unnoticeably less at higher speeds. Different porting and ignition map. Piston is now ventilated, has echo-specific hard coating, has higher thermal durability upper cage bearing, different piston pin and differrent rings.

If it happens with fully charged battery just get it to the dealer. There is 5/2y warranty unit and non-turning off will definitely be covered Normally the membrane button turns it off in any situation.

Can’t understand the idea about “complicated” part. Putting fuel in = putting battery in Pulling starter = pushing ON Turning OFF = turning OFF Only difference - battery saw blinks to indicate brake is engaged and also turns off soon if you leave in the middle of kindergarden or next to the clueless groundies

The blinking green light indicates the chainbrake is on. The meanings of 2 types of blinking warnings are in that book nobody reads called manual Make sure you charge the battery before starting to play.

ECHO DCS-1600 (and now it's successor DCS-3500). Also DCS-2500T with a mesh. And yes, dense mesh is considered an air filter by Stihl themselves - see FSA 135 for reference:

Industry 2nd, to be honest. Otherwise yes, an impressive chainsaw, especially for the companies that need to operate in the areas where IC equipment usage is restricted/prohibited.

It has 2.5kW output, not 3.0 like 550/261. the declared 3kW is consumption (.5kW is turned into heat and other losses). However electric motors do behave a bit differently and even lower output leads to better performance compared to the petrol counterparts.

No. It is a smaller part of outdoor power equipment market and the fastest one to switch to batteries.

Belgium. Average stats say 0.26€/kWh but with all the windmill choices and different supply options (like fixed and periodically reviewed rates) it varies.

Gizmos do get people involved and immersed More screens and numbers, just like 12-band equalizers on the amplifiers 30 years ago. Or vaper community and their measured pleasures of glycol clouds Anyway, the batteries should be simply replaced once it's runtime starts being too short to work normally. Just like when the 2 stroke loses power (which it gradually does over time) and it gets really annoying to start or produce decent torque. They definitely can go up to 1000+ cycles with losing 50% or more of the capacity. Then it is definitely noticeable.

BLi300 Can’t be that cheap. OTOH that picture contains 2.5-5k of charging/discharging cycles that will transfer roughly 1.5MWh of mains energy (brutto) in total. What’s the electricity (kWh) price in UK btw?

I’m just fully resetting any carburettor. Doesn’t take much more time but at least makes you feel sure everythings tip-top afterwards.

Aspen is another thing. Jumping from regular petrol to aspen also requires carb readjustment due to different alkylate atomization properties alone. And yes, after going for Aspen most often it acts like “too rich”, especially on the low end. Anyway for alkylate there is no “linearity” when comparing to all those ethanol spoiled mixtures of unknown age. And honestly and personally I find the alkylates to be the most reliable and steady quality fuels. Yes, they cost more, but there is barelly anything in the engine no matter how old it is. Probably my only negative experience in lifr was an attempt to start some oldschool engine in -24C

Just running ethanol fuel in a 2-stroke after it is set up for non-ethanol causes pretty much lean condition (partly because of the oxygen in ethanol) To counteract this you need to richen the mixture (=dump more fuel volume) for the same conditions. Those 5-10% typically are described as “up to” so it may be never exact.

By replacing 10% of imported (for some countries) oil with locally made ethanol it is a nice chance for a country to influence import/export balance too. It’s quite a sum of money at that level.

This is the hardest part about the battery units. MSA220 claimed 2.1kW at one point and they were not lying - the motor could in theory consume this much energy given the battery could provide it (=36V x 58,3A continuous). Multiply it by efficiency of ~80% and you have the peak output on the PTO shaft. DCS-1600 has 1.73kW actual OUTPUT (it is shown in service documentation) but also has slightly higher efficiency and highest torque (at the moment). Marketing boys from all companies could manipulate the consumption-output numbers but Stihl was kind, smart and polite so they removed it from most of the places on the web. Giving any digits as "granted best", especially for battery saws is misleading the enduser - earlier it was "chain speed" but then again - DCS-1600 is electronically limited over 10kRPM as everything above is very inefficient and there is virtually no torque = no actual cutting at that speed (but a lot of useless heat production). On the paper it looks the slowest but it isn't so in the wood. All in all DCS-1600 and it's upcoming successor are very much on par with MSA220 (to my surprise too!). 540iXP is a bit ahead speed wise but surely not as much as the price is (rebranded 80PX chain on it is really smooth though). As one can predict, lower voltage motors have lower torque.

Of course. You can simplify it down to the customers - the 362's are also professional despite 2-piece engine (top handle being the obvious in civilized countries). This makes: 2511/362/390/4310/501/621/7310 pro line (most are X). So is the present 50V line-up. 310/352/3510/370/420/4510/490/590 farmer line. 490/590 are overbuilt for farmers (downgraded pro units). Probably the hardest part for ECHO is to explain 100% pro grade concept which I tend to simplify - all engines are built to last/withstand the same respective loads/abuse therefore they can be used extensively. The difference in all machines is just design - "farmer" saws being plastic cased as they get less abuse and servicing, pro saws being 3-piece-engined for serviceability and usage requirements.

I’ll simplify: X series - pro saws with 3 piece engine: 25/38/43/50/60/73cc (2511/390/4310/501/621/7310) All others: farmer saws except 35cc horizontal engined ones (362TES/WES) 3 digit numbering was used for old models of the past couple decades, all NEW chassis are getting 4 digit codes, first 2 meaning approximate engine size, 3rd number tells engine generation and the last digit means significant modification of the machine (like 2510->2511). Older ones did not have that “third” digit hence 620->621.

It kinda is in the class of 543XP. Just better.

Everything. They aren’t even in the same class (pro saw vs plastic cased farmer saw). 4310 with 16”bar & chain weighs as much as 4510 naked powerhead. I’m not even going into size/balance/maneuverability/acceleration.

The brass insert shouldn’t come out unless you really abuse it using excessive forces. Kindly ask your dealer if he’d agree to warranty it (yeah, it’s a lot of fuss to change entire frame, therefore KINDLY) Would also be a good chance to inspect if other parts aren’t broken/missing. But yeah, a lot of it is down to how good the dealer is

Oily? Give the drum and the band a shot of brake cleaner or other degreaser and a quick rub once in a while. That’s not brand related, just a common practice on the safety equipment.

CS-7310SX has the lowest vibrations in it’s class. 7310: 4.2/3.8 572XP: 5.2/4.1 MS462: 4.8/3.6

Expect approx. 0,9 sqm of cut area per 100Wh of battery with a well made saw and a sharp chain. This means for example 2x18Vx5Ah batteries should be capable of ~160 cuts of 10x10cm square sticks (that’s 4x4” in royal units). Obviously results may vary if you overload a weak chainsaw or run a powerful one with not much load. In both cases there are additional energy losses.