Compression testing

[jmssaws]

220 in a 90cc is way different than 220 in a 50cc.

 

[Stihlbro]

Depends on what type of work the saw will be doing and what size saw.

Please explain more. 200 ish lbs ok for a saw to run all day. 250lbs is for short run? 150 is a turd?

Sorry fellas, getting off topic of the op's original post. Just making good discussion here.

Joey

 

[czar800]

I was happy to see 225 that's high in my book.

 

[jmssaws]

I've run my 240lb 066 almost a year and haven't had any problems, on 87 octane it did try to diesel on me once.

 

[Redfin]

Your test is valid. You did nothing wrong. I've found the same results. So now when you post a compression reading, should a person state what length hose used? How many pulls to achieve highest reading? Please don't take my post wrong, it's not what you did at all.

Joey

Nope its what I said in the other thread. Length of hose is insignificant, pull till it maxes.

 

[Stihlbro]

Nope its what I said in the other thread. Length of hose is insignificant, pull till it maxes.

It's all good bro!

 

[Deets066]

Please explain more. 200 ish lbs ok for a saw to run all day. 250lbs is for short run? 150 is a turd?

Sorry fellas, getting off topic of the op's original post. Just making good discussion here.

Joey

Just theory but high compression could possible hinder rpm for say cant racing but some say it helps torque for runnin longer bars or stumping. I'm no expert but have read lots of perspectives on it

 

[jmssaws]

I've not noticed a rpm drop from compression.

 

[Stihlbro]

Just theory but high compression could possible hinder rpm for say cant racing but some say it helps torque for runnin longer bars or stumping. I'm no expert but have read lots of perspectives on it

I agree with what you have read, however it seems that now days you ain't building a saw if the compression ain't 200 plus.

Cant racing is small cuts and it's done. Stumping can be longer cuts. So how does the more compression and longer cuts make it better, yeah more grunt, but if it hurts a saw can't racing, does it not with long bars stumping?

 

[Deets066]

I agree with what you have read, however it seems that now days you ain't building a saw if the compression ain't 200 plus.

Cant racing is small cuts and it's done. Stumping can be longer cuts. So how does the more compression and longer cuts make it better, yeah more grunt, but if it hurts a saw can't racing, does it not with long bars stumping?

Good question

 

[jmssaws]

How does it hurt cant racing?

 

[Deets066]

How does it hurt cant racing?

Just theory but too much comp could possibly hold it back from getting high rpm

 

[Redfin]

It's all good bro!

Joey, maybe I should have said Nope im not taking your post wrong? I did this tonight after thinking about the other thread yapping on hose length.

I suppose comp readings would come in really handy when you are cutting squish if you are figuring what you want but I have sent all my jugs off for machining.

 

[czar800]

This is some great popcorn!

 

[mdavlee]

Anything over 200 is getting up there. I wouldn't want to put a 90cc saw on a mill with over 200 lbs of compression and do 8-10 minute cuts.

My Schrader valve is dead in my tester. The last 10 I bought from ebay are clear not white. I should have looked harder when I got them.

 

[jmssaws]

I find every thread on this site fantastic, this is a great place guys

 

[Stihlbro]

Keep it going!

 

[Deets066]

Can anyone elaborate on how high compression affects performance

 

[huskihl]

Anything over 200 is getting up there. I wouldn't want to put a 90cc saw on a mill with over 200 lbs of compression and do 8-10 minute cuts.

My Schrader valve is dead in my tester. The last 10 I bought from ebay are clear not white. I should have looked harder when I got them.

I can still hook you up if you want a few. I sent 2 to paragon builder a couple days ago. Got 8 left.

 

[huskihl]

Can anyone elaborate on how high compression affects performance

From what I've seen, it impedes rpms, but increases torque