Stihl ms290/390 pop-up piston kit - To be sold soon??

[Chainsaw Jim]

Once you cut the step out you'll end up at 0.025"-0.030" which is right on par with an OEM jug.

Wouldn't you get to use the pop up piston after that?

 

[Definitive Dave]

Nate @Black Dog Chainsaw would it help to have identical sets of new tank assemblies,bearings,seals,and cylinder bases and cranks to test with?

EDIT I suck i have only one engine pan in stock
rest of my offer stands if it would be helpful

 

[Gentleman]

If you want a hyway 49mm checked send one of them! If you have a chassis you need rebuilt send one of them to and I'll be sure to return it rebuilt.

I'll send it. Let me know if you need anything else.

 

[Gentleman]

I am sending extra bearings and seals.

 

[Black Dog Chainsaw]

I am sending extra bearings and seals.

fuel lines and filters too, please!?!?

 

[Gentleman]

fuel lines and filters too, please!?!?

You got it.

 

[srcarr52]

Wouldn't you get to use the pop up piston after that?

I can't guarantee the pop-up will clear the squared off combustion chamber, I didn't bother to check since it wouldn't swing without machine work to the cylinder. Still, you'll be in the about same place as using the Cross or an OEM cylinder with more trouble.

 

[Black Dog Chainsaw]

Nate @Black Dog Chainsaw would it help to have identical sets of new tank assemblies,bearings,seals,and cylinder bases and cranks to test with?

EDIT I suck i have only one engine pan in stock
rest of my offer stands if it would be helpful

Do it! I'd need the rear bar stud to lock the pans in.

I've got 2-3 extra OEM engine pans. I'm going to bead blast them at Shaun's shop so I have 3-4 OEM pans to mess with. I tend to leave the pan locked into a tank assembly.

 

[Chainsaw Jim]

I can't guarantee the pop-up will clear the squared off combustion chamber, I didn't bother to check since it wouldn't swing without machine work to the cylinder. Still, you'll be in the about same place as using the Cross or an OEM cylinder with more trouble.

How do you think the piston would hold up if you were to build up the entire crown to make it tall enough so you can cut the squish band wider? I can think of a few clam shells pistons I wish were a tad bit taller.

 

[srcarr52]

How do you think the piston would hold up if you were to build up the entire crown to make it tall enough so you can cut the squish band wider? I can think of a few clam shells pistons I wish were a tad bit taller.

I did that for someone for a Pioneer 650... can't remember who it was now.

It adds a lot of mass, the piston shrinks a little above the ring land no matter how careful you are when welding and it's really hard to weld all the way to the edge of the piston so it will finish off nicely. Other than that... it can be done.

 

[Dub11]

Can I get a pop up for my wildthing?

 

[beaglebriar]

Can I get a pop up for my wildthing?

Send me the piston.

 

[Dub11]

Send me the piston.

You make pop ups?

 

[beaglebriar]

You make pop ups?

I don't make a habit of it but yes I can.

 

[Dub11]

I don't make a habit of it but yes I can.

Nice but Iam sure it would coast twice as much of what the saw is worth plus I was just playing

 

[beaglebriar]

Nice but Iam sure it would coast twice as much of what the saw is worth plus I was just playing

I figured...Just super glue a nickel to it. Fabz says it works great.

 

[Red97]

I did that for someone for a Pioneer 650... can't remember who it was now.

It adds a lot of mass, the piston shrinks a little above the ring land no matter how careful you are when welding and it's really hard to weld all the way to the edge of the piston so it will finish off nicely. Other than that... it can be done.

Me, homelite piston. Haven't gotten around to finising it yet.

 

[Dub11]

I figured...Just super glue a nickel to it. Fabz says it works great.

I got a fabz kit coming in the mail any day now.

 

[Al Smith]

It's kind of unusual to think of much more than hogging out a muffler or maybe widening the exhaust port a tad on a clam shell design .

Raising the bearing pockets would be a monumental pain in the buttocks to say the least.Taller piston I suppose would work better .I don't know too many people who would even take the time on a clam shell .I do wish you a lot of luck and am curious how this turns out .

 

[beaglebriar]

I know a guy that loves working on these saws. Makes some pretty good runners out of them too.

Everybody and their brother owns a 290 around here (don't ask me why). I can see the market for these pistons being huge. Tell a fella you can rebuild his saw cheap and boost performance, he'll jump on it.