The LD110 Adventures.

ImpulseRocket89

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Apr 16, 2014
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350
For sure you can find a 54mm piston, I think 298s are 54mm
Sorry 288s
The only issue I forsee with most saw pistons will actually be the skirt height. The exhaust port floor is pretty low on this 110 cylinder. I checked a couple of Stihl pistons I have sitting around, and they leave a pretty large gap on the bottom when at TDC. The original 110 piston is roughly 22mm from wrist pin center to the bottom of the skirt. The 380 piston I have on hand is about 8mm shorter (rough guess).

I guess it wouldn't be too unrealistic, if you really wanted to dive in and do some serious machine work, to make a spacer for the bottom of the cylinder and remove the same from the top. The ports are so conservative that it would be very possible to do this and make it work. It would definitely open up the transfers a ton. The only issue with that whole plan is the intake port is too high. You could fill the intake port in and make the engine a case reed though. Doing that would allow you to run about a 5-6mm spacer, which would almost fully open the exhaust port and open up the upper transfers almost 80-90% with no other work. You would have to remove the very top cooling fin from the cylinder to pull that off though as the deck height up to the fin is 3.5mm, and the fin itself is 2.5mm thick.
 

Chainlube

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Jan 5, 2020
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6,233
Saw are piston port and don't have much skirt, I was just noting a 54mm piston. The one good thing about a exact match piston is you can bore the jug to the piston.
Most saws are short stroke 34-38mm, that's how they rev higher. The big saws not so much 9500ish no load speed, even less when it's in wood, as compared to a smaller saw, my 61 has a no load speed at 12,500.
 

ImpulseRocket89

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Apr 16, 2014
Messages
350
Saw are piston port and don't have much skirt, I was just noting a 54mm piston. The one good thing about a exact match piston is you can bore the jug to the piston.
Most saws are short stroke 34-38mm, that's how they rev higher. The big saws not so much 9500ish no load speed, even less when it's in wood, as compared to a smaller saw, my 61 has a no load speed at 12,500.
Oh I know. My MS460 is quite happy staying below 10k, and usually around 6-7000 when making a cut into anything 12-18" with the 24" bar I have on it. It's got some very mild port work done to it and a 2 chamber muffler, so it isn't even pushing "race saw" power. It and the 660's are close to the same in stroke to these engines, which is probably why they are a popular choice for Frank motors and the basis for the Phantom. I can't imagine having a saw screaming at 12000. That's just crazy to me lol.

I enjoy theoretical engine build discussions like this where hard numbers can be thrown around. I enjoy just seeing if I can make things work. Now I kind of want to see if I can make something work.
 

Chainlube

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Jan 5, 2020
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Any good bush saw is going to have peak power around 7-10k, if you set it up with the bar off, the no load speed will be considerably higher. I kinda remember seeing in the specs for the 460 that the highest permissible rpm with a bar and chain is 13,500. So you should be running a bit more rpm in the cut with that saw.
 

ImpulseRocket89

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Apr 16, 2014
Messages
350
Any good bush saw is going to have peak power around 7-10k, if you set it up with the bar off, the no load speed will be considerably higher. I kinda remember seeing in the specs for the 460 that the highest permissible rpm with a bar and chain is 13,500. So you should be running a bit more rpm in the cut with that saw.
I didn't touch the exhaust port at all. I went for a strong pulling saw more than a screamer. That may be why.

I also don't claim to be a saw expert, or 2 stroke expert, by any stretch of the imagination. I am sure somebody other than me could get better results out of it. I just cleaned up and opened up the lower transfers and intake port a bit.
 

Chainlube

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I didn't touch the exhaust port at all. I went for a strong pulling saw more than a screamer. That may be why.

I also don't claim to be a saw expert, or 2 stroke expert, by any stretch of the imagination. I am sure somebody other than me could get better results out of it. I just cleaned up and opened up the lower transfers and intake port a bit.
I'm not saying anything about the job you did, those are just stock specs. I think you may be underestimating how many "R"s you're pulling when in the wood.
 

weefek

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May 14, 2022
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371
Can you link to or give a better description as to what you used to polish the head?
 

Karl Snarl

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Sep 20, 2019
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5,698
Can you link to or give a better description as to what you used to polish the head?
Probably just a buffer pad and some polishing/buffing compound. Comes in a stick, like butter. he mentioned the grits. Slap it in a hand drill and spin on some compound. Then polish away.
 
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