Echo's new top handle: CS-355T

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Who TF is chris j and what TF was the question? and all you poor precious little echo babies crying and bawling, get a grip, some clown asking me if i have "proof" of all the saws I've seen rattle to death in the bush.. hoho no idea this crowd



yep! didn't prove me wrong.:msp_rolleyes: couldn't come back with anything except useless drivel:spam:
come on pp boy, back up your claim. seems all you can do is throw insults when confronted with your own claims. wheres your proof of this 'death rattle'? somebody who claims a company is so bad would have something other than insults to fall on. heck, you'd think this would be a priority for that person considering said person is constantly whining and complaining about echos' quality.
so pp boy, why is it that people who buy these 'death rattle" machines are crybabies? please explain as it seems they are quite happy and don't seem to be snivling or complaining one bit with their purchase. even going so far as to buy more of them later. so come on pgg, what makes them bawling crybabies? seems only one person here crying about an echo.
'hoho no idea this crowd' what exactly does this mean? lots of people here right in this thread have run far more saw manufacturers, weather it's top handles or not, and they seem to be buying these little echos'. so why would you figure they don't have an idea? seems they have a far broader idea than some child with nothing better do to than dry hump a stihl and call it the best he's ever had.
 
yep! didn't prove me wrong.:msp_rolleyes: couldn't come back with anything except useless drivel:spam:
come on pp boy, back up your claim. seems all you can do is throw insults when confronted with your own claims. wheres your proof of this 'death rattle'? somebody who claims a company is so bad would have something other than insults to fall on. heck, you'd think this would be a priority for that person considering said person is constantly whining and complaining about echos' quality.
so pp boy, why is it that people who buy these 'death rattle" machines are crybabies? please explain as it seems they are quite happy and don't seem to be snivling or complaining one bit with their purchase. even going so far as to buy more of them later. so come on pgg, what makes them bawling crybabies? seems only one person here crying about an echo.
'hoho no idea this crowd' what exactly does this mean? lots of people here right in this thread have run far more saw manufacturers, weather it's top handles or not, and they seem to be buying these little echos'. so why would you figure they don't have an idea? seems they have a far broader idea than some child with nothing better do to than dry hump a stihl and call it the best he's ever had.

He wont back it up, he has a habit of disappearing from threads when his story(s) get challenged
 
cs-355 four week run time

a friend of mine got a 355 when they came out and has about 4 weeks of run time on it now.
i was raised on stihl saws and echo trimmers/blowers and had no problem with them.
out of curriosity, we tached the 355 fresh out of the box at 13,200 wot. today it is taching at 14,200-14,600 rpm wot with no mod or carb tweaking yet.
like everyone, i know echo has floundered in the chainsaw department for the past few decades but only time will tell if they have turned over a leaf with the 355.
 
Looks like the same kind of porting as the CS400 which is a strong saws for 40cc. Steve

Same occurred to me. Echo has some of the nicest quality cylinders I've been in.
 
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Here is a pic of a parallel twin TZ250 engine:



Untitled by zweitakt250, on Flickr

A "clamshell" design.

The top end, crankshaft and jackshaft, and entire gearbox can be serviced without removing the main case from the chassis.

Sound engineering.


Oh darn! I always follow Echo threads with interest. But then you had to post up some SERIOUS two stroke machinery....which brings me back to my racing days....sigh.

Thanks for the real two stroke memories.

Now I will go back to thinking about working on my hot rod Echo trimmer again, as well as starting my Kawasaki H1 500 restoration.
 
I am late here but better late than never. My work got the new echo as a demo saw in June and the husky. The echo was allot better than the husky and not to far off from the stihl. For the price I would buy it.
 
We got our first shipment of the 355T's in this week. Echo did a very good job on this saw, runs really well and has good power. Still waiting on our T540's from Husq and not sure when we will get them.
 
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Thru all the din, nobody seemed to notice what i think is most significant. This saw seems to lack the catalytic converter found in the cs330/360. Looks like a muffler mod will be little more than enlarging the muffler outlet. the exhaust port in the cylinder looks to be less restrictive too, especially where it bolts up to the muffler. In one of the videos the saw was run and indeed it did sound different from the 330/360 which typically stumbles a bit from 7000 to 10,000 rpm. By the way, I have both the 330 and the 360 which i purchased new around five years ago, primarily for use as climbing/trimming saw. Like all the echo top handles I have owned over the years, they just keep on keepin' on. The only way you can kill them is by dropping them from great height or, more often, running over them with the truck or chipper. Even then you can usually resurrect them with $100 worth of plastic.
 
The cylinder layout looks similar to my CS346. Does the 355t have a reed valve as well?

Not sure why there's so much disdain for reed valves. They were introduced on Yamaha motorcycle engines back in 1973 and have proven to be an asset to engine performance. When it was first introduced by Yamaha on their RD series bikes, it was promoted as "Torque Induction" system. It's supposed to make the bike more manageable and broaden the power band, so they say. The RDs I've ridden have a rather abrupt power curve. Everything is fairly docile until about 5500 rpm then it's like throwing a light switch. Hang on!

What's the method to display the image rather than the link?

Here's a '74 RD350, my favourite motorcycle:

View attachment 260532
 
An abrupt power curve has to do with the ports and pipe, you can make a piston port, reed valve or rotary valve engine that has a broad power curve, and conversley you can make any one of them a light switch motor with an abrupt and brutal hit of power when it gets on the pipe.

The reason saw companies choose their induction pp vs reed has all to do with packaging. Echo chose to lay the engine flat with the carb forward and hence the reed valve was necessary for that configuration. I don't care for the design of the echo reed, but it's simple, compact and inexspensive.
 
An abrupt power curve has to do with the ports and pipe, you can make a piston port, reed valve or rotary valve engine that has a broad power curve, and conversley you can make any one of them a light switch motor with an abrupt and brutal hit of power when it gets on the pipe.

The reason saw companies choose their induction pp vs reed has all to do with packaging. Echo chose to lay the engine flat with the carb forward and hence the reed valve was necessary for that configuration. I don't care for the design of the echo reed, but it's simple, compact and inexspensive.

A reed or rotary valve lets fuel induction be placed directly on the crankcase rather than on a port in the cylinder wall. I may be wrong but I think that max rpm is limited by a reed valve because, like poppet valves, they can start doing weird things above 10,000 rpms. So typically they are used in applications where a wide power band and abundant low end torque is valued over horsepower, like the echo 3400. Also you have more latitude with transfer and exhaust port timing, since you don't have to worry about overlap with the intake ports. Haven't seen the specs but I'm sure the355t is piston ported.

the rd-350 was a great bike but in the same era you had the yamaha tz700. it was so powerful that few riders could master it. it redlined somewhere up in the stratosphere.
 
I don't claim to be an expert on reed valves, but as far as I know all of the state of the art highest hp two strokes today all use reed valve induction. Not sure why the rotary has been ditched, but you'll be hard pressed to find one on an engine built in the past 10 years (excluding rc engines) 125cc tag and icc kart engines are reed valves, gp bikes are reed valve and snowmobiles are reed valve. There is no rpm limit for a properly designed reed valve, there are 100cc kart engines that have turned 20,000 rpm, and 125's that are running 17,000 rpm (some nearly 18,000), these engines start making their power at 10,000 rpm. Not new technology either as my 80's vintage kart engines would make their power between 10,000-15,000 rpm and the engines introduced in the early 90's were turning 17,000 rpm.
 
So, why such disdain for reed valves in a chainsaw engine? I've read a few posts where people say engines with reed valves are slow? That's something I've been trying to get my head around.

I've got quite a few two cycle engines. Many with piston port induction and many with reed valves. Personally, I don't see any difference between them. I've alway thought that technically, reed valve engines are the preferred choice because reeds allowed for more flexibility.

By the way, the TZ700 was boosted to the TZ750 which King Kenny Roberts won quite a few races on, including one mile flat (dirt track) races. The machine was so powerful and dominant that the AMA banned it, claiming that it was too dangerous to race. Fact of the matter was that they were humiliating the HD XR750 racers and the AMA was worried about losing it's Harley Davidson fan base. However, Kenny Roberts did say it was the scariest machine he'd ever ridden but wasn't intimidated by it once he learned how to use it's power.
 
So, why such disdain for reed valves in a chainsaw engine? I've read a few posts where people say engines with reed valves are slow? That's something I've been trying to get my head around.
I've got quite a few two cycle engines. Many with piston port induction and many with reed valves. Personally, I don't see any difference between them. I've alway thought that technically, reed valve engines are the preferred choice because reeds allowed for more flexibility.

By the way, the TZ700 was boosted to the TZ750 which King Kenny Roberts won quite a few races on, including one mile flat (dirt track) races. The machine was so powerful and dominant that the AMA banned it, claiming that it was too dangerous to race. Fact of the matter was that they were humiliating the HD XR750 racers and the AMA was worried about losing it's Harley Davidson fan base. However, Kenny Roberts did say it was the scariest machine he'd ever ridden but wasn't intimidated by it once he learned how to use it's power.




It's not that the reed valves make the engine slow.
They were just used on slower designed engines.


Mike
 
So, why such disdain for reed valves in a chainsaw engine? I've read a few posts where people say engines with reed valves are slow? That's something I've been trying to get my head around.

I've got quite a few two cycle engines. Many with piston port induction and many with reed valves. Personally, I don't see any difference between them. I've alway thought that technically, reed valve engines are the preferred choice because reeds allowed for more flexibility.

By the way, the TZ700 was boosted to the TZ750 which King Kenny Roberts won quite a few races on, including one mile flat (dirt track) races. The machine was so powerful and dominant that the AMA banned it, claiming that it was too dangerous to race. Fact of the matter was that they were humiliating the HD XR750 racers and the AMA was worried about losing it's Harley Davidson fan base. However, Kenny Roberts did say it was the scariest machine he'd ever ridden but wasn't intimidated by it once he learned how to use it's power.

yes, i saw kenny roberts race a few times, laguna seca, 180 mph in the straights. i didn't know he ever took one to the mile tracks. the xr750's were awesome on the dirt ovals. i always wanted one for a commute bike. the yamaha td250 road rashers were used in the junior class. they were fast too. i think the main problem with the tz700 was that it had too much power for its frame. too much throttle in a turn would result in tank slappers. but i guess that has nothing to do with cs355t's or piston porting.
 
I think there are a combination of factors as to why most saws are piston ported. The main factor is packaging. A saw engine needs to be light and compact as well as inexpensive. Since saw engines don't use a tuned pipe, they just don't flow enough air/fuel to where a reed valve induction would be a benefit. The piston port conveniently locates the piston higher on the cylinder which allows the fuel tank to be mounted right under it, or at least in the case of most 50cc and larger saws. A reed valve adds additional expense and doesn't give a performance gain for the hp derived from a saw.
 

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