Based on the ring on the crown of the piston, I would have to guess that the Cross cylinder has a reverse taper on the squishband.
Can't start my 92cc saw
- Thread starter Bedford T
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looks to me like the piston rattled around in the cylinder during shipping and got a bit of a wear pattern to it...but that's assuming it was pushed into the cylinder to save on shipping space...
That can only happen if there's a reverse taper on the squishband.
Or there's some casting flash somewhere on the squish band that is similar to what appears to be in the exhaust port.
the 800 lbs gorilla in the porting room is the exhaust & transfers. Quite a bit different. Guess time will tell on how it runs! Figure if it out pulls a 35 dollar BB it should be a win wouldn't you think? Might take me a bit to build this top end into a MS660. Would have to tear apart either the "bling" saw or the original 56mm saw which is running...perfectly and I'm reluctant to tear it apart. Maybe I'll just have to build yet another one.
The squish band has seen a machine tool. could be machining aberrations as well...
I don't know, but I think the "cross" top end is worth a try, don't you think? It doesn't look bad even on close up. Caber rings are also a plus, A little junk here and there but its really not bad at all. My guess is it will run different. Might be an improvement but for 125 bucks, why not give it a try?? I absolutely will not measure or post timing numbers, it simply doesn't matter; and I really have to move onto another project set. Looks like a different power band was designed into this and if folks buy and like it, that's a win in my book.
Not to beat a dead horse, but 1) I agree with those who say the carb leak could not cause the cylinder scoring, the is another issue. 2) Fuel in the crankcase (from the leaking carb) will make the saw feel like it has a lot of compression, even when it does not, and 3) don't forget to pressure test the carb in addition to pressure testing the saw.
Never test over 10 lbs, but test both the fuel line and impulse line on the carb.
That MMWS Cross jug (comes with caber rings) would likely be a good upgrade to one of these saws, and I think they are currently on sale!
Never test over 10 lbs, but test both the fuel line and impulse line on the carb.
That MMWS Cross jug (comes with caber rings) would likely be a good upgrade to one of these saws, and I think they are currently on sale!
The torch has been passed...
Chris-PA
Where the Wild Things Are
Good eye. Even worse than a flat band.
As stated before, meteor piston with caber rings, $40, fits 54mm. Meteor is as good as OEM in most applications. Don't use the piston pin circlips that comes with aftermarket kits, OEM only, most on here will tell you the same.
OEM pistons are often close to the same price, and are usually lighter than Meteor pistons. Sometimes, Meteor has wider skirts (which may be desired if porting).
The torch has been passed...
I wouldn't consider it a passing of the torch so much as an OCD type mind needing to satisfy it's curiosity...I'll likely be on to some other all consuming pursuit by this time next year...
ncfarmboy
Addicted to ArboristSite
I know this a 660 but yesterday I bought OEM MS460 piston from my new Stihl parts source/dealer $40.00 + tax.
Shep
Shep
