Recent content by upstateamish

Current Prototype #3 specs: for those who wish to recreate what I've got here Case - 365/372 variety with material removed to fit the diameter and width of the crank Chain - 24" bar with dukes hard chrome 3/8 .050 full chisel skip tooth Cylinder -57mm 390 big bore from wolf creek (non-Titanikel)...

Got a chance to get a bar and chain on it and a couple test cuts in some ash. Did a video of side by side cuts with my 500i. The saw I ran was the 500i, but looking at how close the numbers for cuts 2 and 3 are, I am chalking up 500i's 1st timed cut to not using as much pressure as the...

Running echo red armor @ 40:1 Piston / cylinder look decent. wiped things down, tweaked the carb slightly and it doesn't seem to be dying at idle, so I'll start heat cycling

3rd run, getting it tuned in a bit more, I think I've almost go it dialed in so it will rev and won't die after sitting at idle for a little bit. Assuming things look good once I pull the muffler and check things over one last time I should be able to get some heat cycles in over the next week.

ok, I believe I found the source of that knock. I sheared the timing key on the flywheel when the lock washer came loose. I happen to have a spare (as I'll be doing prototype 4) so I swapped the good one on. I figure this one can be used later for adjusting timing if I need to. Also added the...

Alright. after searching through the bins for a bunch of random parts along the way... Got it together. I have a couple parts that still need to be ordered. But first fire is a success! Long form vid (skip to 45 seconds if you don't want to see me yarding away on it...) - I didn't hear it...

Parts arrived over my lunch break! I installed the new seal and it is now holding pressure/vaccuum. So I started pulling the rest of the parts out to finish the build.

Yeah, I don't have an actual 385/390 to reference but from what I can tell in my research they changed their bearing style to move to an integrated seal (like the 562 series saws.) Here's one I found...

Me too! If it works, the next prototype will need some additonal case trenching on the clutch side to case match the transfers. And when I pressure vac tested last night and had a small leak around the crank bushing, so I've pulled the seal and bushing out and did a small amount of 1184 around...

Ok, some forward progress, I have the short block together (well, as far as I can get tonight) - new crankshaft bushing made - piston lightened a couple ounces - new 'artisan crafted' choke lever to hopefully allow the choke to have full range of motion. Numbers: - squish: 0.027" -...

Agreed on that amount of blowdown it seems like a lot. But I was reading somewhere (maybe this thread?) that this particular bigbore kit was similar to a dolmar 7900 cylinder (e.g. it has tight thin transfers so it needed the additional blowdown to move the air?) I'll have to dig back through my...

Yup, you are correct that's the before I pulled things back apart and took material off the clutch side of the crank. Good idea on using the feeler gauges for spacing & great idea on tapping the cylinder for plugs (I ... totally should have thought of that seeing how this is not the first one...

Alright... I guess I had to take it back apart afterall. (and trim the crank down on the clutch bearing spacer side) it wasn close but not 100% centered. Would turn freely but when I got the piston/cylinder on the connecting rod would hit the clutch side crank lobe ... so I pulled things apart...

Initially there was some slight rub on the crank lobe while turning things over by hand with everything dry. However, after messing around with it a bit more I think I might have spoken a bit too soon on having to tear things apart. I've alternated carb cleaner & wd40 turning things over, and...

I have been working away on other life projects and work is getting in the way but on the down time I'm still working on/getting closer with this. I've got most of it clearanced. Test fit the top end for the piston (confirmed it doesn't bottom out) Turned down the Cylinder skirt a bit to...