What barmount for Echo CS621sx

[Fatherwheels]

The top ring is NOT any further towards the top on 621. See the picture (621 piston is on the right).View attachment 867238

Thanks @Piston Skirt , that clears that up. Looks like a nicely finished piston.

 

[Piston Skirt]

Thanks @Piston Skirt , that clears that up. Looks like a nicely finished piston.

They both are. 621 has a different plating though.

 

[Fatherwheels]

Whinbush - I'm not linked to this company but they sell bar adaptors and a very wide range of bars and chains: www.chainsawbars.co.uk. The web site has a bar and chain search facility which, if nothing else, will help you identify a bar and chain combo for your saw.@

Thanks @Teemore , I bought there before, knew I saw the adaptors advertised somewhere close to me,

 

[Fatherwheels]

They both are. 621 has a different plating though.

I didnt realise they had plating, whats it for, I heard of race pistons with plating work
done to make certain areas more resistant to wear heat and such.
Did the ring pin location move from where it was on the 620.

 

[Piston Skirt]

I didnt realise they had plating, whats it for, I heard of race pistons with plating work
done to make certain areas more resistant to wear heat and such.
Did the ring pin location move from where it was on the 620.

620 “tin” plating is for anti-seizure during run-in period.
621 has a permanent plating that increases surface hardness, has self-lubricating properties and reflects the heat. Some other models have this one too.
Pins are at the same places but the shape is different as the rings are also different and lock the pins in case they get loose.

 

[Fatherwheels]

620 “tin” plating is for anti-seizure during run-in period.
621 has a permanent plating that increases surface hardness, has self-lubricating properties and reflects the heat. Some other models have this one too.
Pins are at the same places but the shape is different as the rings are also different and lock the pins in case they get loose.

Thats all good stuff, interesting to see their aproach, no magnesium yet, not that I ever want to see it,
dont get that at all, quicker to mold and eject, with weight being the only bennefit I see.

 

[Piston Skirt]

Thats all good stuff, interesting to see their aproach, no magnesium yet, not that I ever want to see it,
dont get that at all, quicker to mold and eject, with weight being the only bennefit I see.

Low piston weight gives a nice possibility to have less fat on counterweights which leads to much lighter engine and also lower vibrations. Everything else is mostly downsides

 

[Fatherwheels]

Low piston weight gives a nice possibility to have less fat on counterweights which leads to much lighter engine and also lower vibrations. Everything else is mostly downsides

I concur, the MS400 seems to be the only saw with the magnesium piston,
I think the coating on that piston may be more interesting, they have Ghosting
on a lot of Stihl pistons in the Strato saws, wonder if the special coating is
to address that, along with thermal protection to the piston.

 

[Piston Skirt]

I concur, the MS400 seems to be the only saw with the magnesium piston,
I think the coating on that piston may be more interesting, they have Ghosting
on a lot of Stihl pistons in the Strato saws, wonder if the special coating is
to address that, along with thermal protection to the piston.

I won’t be surprised if more mag pistons will appear soon, especially if 400 proves itself.
Anyway magnesium is complicated stuff to get plated or coated so it’s quite an expensive way to shave weight.