562xp / 28" techlite bar / Fresh Youtube video

[Terry Syd]

Crikey TK, chill out - I'll explain how to do it.

First off, EGTs are not the same Cylinder Head Temps. As I was modding the 450 Husky, I had to keep running the saw richer to keep it alive. I was basing that upon a couple of things. The spark plug temp was showing quite high while the mixture strength in the chamber was showing it to be on the rich side. The most significant indicator was the piston.

I had a previous piston that I had run for quite a while and had made some timing changes to. I could compare the darkness of the burnt oil on the bottom of the two piston crowns. The new piston was getting a lot hotter. The real worry was in the taper to the piston. The piston crown was now getting so hot and expanding that it had used up all the taper. I was getting full wear around the top part of the piston above the ring. I thought I might have to shape a 'clearance band' on the piston to take the power up any further.

I made a few changes to the fins of the cylinder to gain a better flow and blocked off the air injection - the temps dropped immediately. I pulled the plug after doing a plug chop and with the same carb settings and the plug was now showing a chocolate brown rich setting. The piston now has a layer of carbon on the area above the ring. Since then, I have upped the power some more and everything is still running at an acceptable temperature.

I didn't say I recorded an increase in power by blocking off the air injection. I mentioned Timberwolf's research that he did with monitoring the increase in temperature of the air inducted into the airbox. You could send him a PM and see if he will explain how he did the measuring.

ST, with the air injection blocked off and the air primarily entering from the back of the saw, there is much less trash in the air box. I still get an amount of dust that enters from the left side through the area of the primer bulb and carb screw access, but that is minor compared to the stuff that used to come in through the air injection.

 

[SawTroll]

HAHA!!! I didn't think it would, and it shouldn't anyway. I agree that it makes more sense for you to get the XP version. I'd do the same thing if I was only going to get one of them, and like you I hardly need another saw.

My main point was that the 555 should not be dismissed as just a watered down version of the top saw in the family as often happens to other "little brothers" like the 365 and 353.

Well, I didn't think you would either, but I need a new 60cc saw like I need a boil in my ass, and want the best when I get one - that will be my only reason to get one, when I already have an Euro 361 with an "Andy" muffler on it - I just can't wait to compare them!

 

[mikefunaro]

Redacted, saw new thread!

 

[TK]

Crikey TK, chill out - I'll explain how to do it.

First off, EGTs are not the same Cylinder Head Temps. As I was modding the 450 Husky, I had to keep running the saw richer to keep it alive. I was basing that upon a couple of things. The spark plug temp was showing quite high while the mixture strength in the chamber was showing it to be on the rich side. The most significant indicator was the piston.

I had a previous piston that I had run for quite a while and had made some timing changes to. I could compare the darkness of the burnt oil on the bottom of the two piston crowns. The new piston was getting a lot hotter. The real worry was in the taper to the piston. The piston crown was now getting so hot and expanding that it had used up all the taper. I was getting full wear around the top part of the piston above the ring. I thought I might have to shape a 'clearance band' on the piston to take the power up any further.

I made a few changes to the fins of the cylinder to gain a better flow and blocked off the air injection - the temps dropped immediately. I pulled the plug after doing a plug chop and with the same carb settings and the plug was now showing a chocolate brown rich setting. The piston now has a layer of carbon on the area above the ring. Since then, I have upped the power some more and everything is still running at an acceptable temperature.

I didn't say I recorded an increase in power by blocking off the air injection. I mentioned Timberwolf's research that he did with monitoring the increase in temperature of the air inducted into the airbox. You could send him a PM and see if he will explain how he did the measuring.

ST, with the air injection blocked off and the air primarily entering from the back of the saw, there is much less trash in the air box. I still get an amount of dust that enters from the left side through the area of the primer bulb and carb screw access, but that is minor compared to the stuff that used to come in through the air injection.

Sorry, the way I read it it sounded as though you had gauged proof of these doings. I was curious as to how you measured your findings or if it was a trial and error, see it as it happens thing. I just couldn't imagine someone going through that much work to gauge temp readings on a saw. Wasn't trying to call you out, just curious as to how you came to those conclusions.

 

[mikefunaro]

You can buy a remote infrared thermometer for about $40-$50 on amazon. I bought one and have been playing around with it. I need even temperatures on my pizza stone before I throw the dough on. if you just needed external temperature of the cylinder this would be quite easy with the thermo gun.

 

[Terry Syd]

The problem with all those secondary indicators (guages, thermometers) is that they don't give you the real information that you need. The most important piece of information is when is the diameter of the piston going to get bigger than the bore diameter. The wear patterns on the piston can give you a better idea of when that is getting close to happening.

Unless you run a couple of engines to failure and monitor the guages while it happens, all the guages are is an abstract number. You might have an idea, but it could be well off the mark.

Yeah TK, I do go through all that work. I've pulled top-ends off bikes and lightly sanded high spots on pistons, put 'em together, run 'em a bit harder, pull them down, etc. I'm a compulsive tuner, I can't leave things alone. I had this saw two days into the warranty and had to start pulling it apart. I had never worked on a chainsaw (or even heard of a strato) and this thing just sat there beckoning me to pick up a wrench.

I learned a lot about chainsaws and how to set up a strato. I just recently did my last bit of work on it by setting the pop off pressure in the carb to pick up a broader powerband. I'll get a link in a bit in case you're interested in doing some fine tuning of your engines.

EDIT: http://www.arboristsite.com/saw-building-101/107976-11.htm

The last two pages of that thread discuss POPs. I had a bugger of a time finding any documented information, but that is the best I could do and it seems to work.