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How thin could a person mill the piston skirts to cut weight. What is the thinnest....thickness a person could safely go with piston skirt thickness, before problems would surface? What would the problems be?

Sam
 
There fairly big......but nothing you can't fix.

bbbp46014.jpg
 
I vote baileys (as long as they dont send me a catalog):hmm3grin2orange: :hmm3grin2orange: :hmm3grin2orange: :hmm3grin2orange: :hmm3grin2orange: :hmm3grin2orange: I have been hoping to try one myself but I cant seem to burn up a cylinder.
 
Slamm said:
Apparently, it was easier to ask us another question than to just answer my question?

Sam

He's machining the squish area to reduce the size of the combustion chamber to increase compression. Saw builders typically do this in combination with machining the top of the piston into a "pop-up" design where there's a centered dome that rises up into the combustion chamber further increasing compression.
 
He's machining the squish area to reduce the size of the combustion chamber to increase compression. Saw builders typically do this in combination with machining the top of the piston into a "pop-up" design where there's a centered dome that rises up into the combustion chamber further increasing compression.


Correct but......don't forget you must cut the base to bring the cylinder back down for correct squish height.....and doing that retards your exhaust and tranfer port timing......so you should raise your ex/tran ports back to at least stock porting.
 
So in that photo all of those chips came from just a little machining of the top outer edge of the cylinder? How much did you take off?? Those seem like .040" or bigger chips.

How much static compression is produced for the amount of metal that you take off of the cylinder/piston??

For instance do you machine .04" off the top of the cylinder/combustion chamber.....then .08" off the bottom of the cylinder and then .08 off the top of the transfer ports?

That seems like a lot of work, is there much gained for this?

Is it very noticeable?

How much does it cost to have this done to a saw..066?

Do you have to change anything on the intake or exhaust ports? Because now those have changed as well?

Do you change anything on the pistons transfer areas?

Just wondering,

Sam
 
As we all know, first impressions are lasting impessions. When the BB came out, many weren't that impressed. It now sounds like a lot of improvements have been made. What I'm trying to decide is, how many of these OEM votes are based on those first impressions? Are they saying, "I don't know if the BB is good or not but I know OEM is"? I understand that arguement. But think about it. If the quality, construction, and design issues have been addresses, why not go for the extra 7cc? I'd love to see Grande Dog chime in here.
 
Additionally, with in reason, if you are doing the porting who cares what that is like from the factory on the BB's?

My opinion,

Sam
 
I just got a 044 bb kit from baileys. It looks ok, but I am not very impressed with the casting quality in the intake, exhaust and transfer ports. A lot of uneveness and casting flash. I have started cleaning it up and it seems to be ok after some clean up work, but pretty rough as received. For the price though I guess not too bad. We will see how it runs once I am done.
 
Agree Brad, it's more torque if nothing else. Is 15-15.5k rpm a little ambitious for a work saw of that displacement?

Perhaps. However, my 066 RL is running 14,300 with no change in intake timing or duration. Since I didn't change the squish, the jug didn't get lowered. If I were to go back in there, I would add some intake timing and likely see a RPM increase. It still probaby wouldn't see 15K though. And I won't raise the exhaust to get it. Torque is more important. I'l just run a bigger sprocket to get my chain speed in that case.
 
I just got a 044 bb kit from baileys. It looks ok, but I am not very impressed with the casting quality in the intake, exhaust and transfer ports. A lot of uneveness and casting flash. I have started cleaning it up and it seems to be ok after some clean up work, but pretty rough as received. For the price though I guess not too bad. We will see how it runs once I am done.

How's the bore and combustion chabmer look though? I don't care about the finish of the ports at all since I'll be grinding on them anyway.
 

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