Differences 45-52-58-(62)cc chinease zenoah clones

[NSEric]

I ported one of each size of these saws.
The 45 runs pretty good with a base gasket delete(I still had a ton of squish but 200psi of compression), wider intake, little less than 1/16 off the pistons intake skirt, widening of the lower transfers(mostly on the exhaust side), wider and a little less than 1/16 higher exhaust with the top edge of the piston also cut down the same amount the exhaust was raised on the sides by the transfers. I cant grind the top of the transfers with my dremel hence the piston cutting.
The saw gains over 1000 rpm in the cut ported, its a pretty good gain for a few minutes grinding and top ends are 20 bucks if you mess it up.

With the small stock carb the ported 45 runs right with the bigger cc versions of this saw, If you put a 365 carb on tho, the 58 and 61cc versions scream.

 

[Piotr Pakuła]

how many rev. for min.

 

[NSEric]

On the ported 45 the max revs went from 11500 to 13000 and it was running about 10000rpm while cutting. These dont sound like much but these saws cut at around 9000rpm stock, they're good running little saws but not fast stock, there's no point leaning them out too much for high rpm stock when they drop to 9000rpm in the cut.
My ported big carb 58 max revs 14500 and cuts at 12000rpm, my 61 with the same mods max revs 14000 and cuts at 11500rpm. I like the 58 better, its the best cc for this saw cassis, the cases wont feed the 61 properly IMO.

 

[Johnsonlong]

I have a neotec ncs6200 apart and it seems to me it may fit this form it's a 62 CC power saw aluminum crankcase dual open port transfers with two ring piston, non-strato adjustable jet carb direct bolt on cylinder about the same size bolt pattern as a Husqvarna 55 I will check and see if they are swappable as far as bolting them on also I will be recording the timing numbers before putting it back together.

 

[RedneckChainsawRepair]

I have a neotec ncs6200 apart and it seems to me it may fit this form it's a 62 CC power saw aluminum crankcase dual open port transfers with two ring piston, non-strato adjustable jet carb direct bolt on cylinder about the same size bolt pattern as a Husqvarna 55 I will check and see if they are swappable as far as bolting them on also I will be recording the timing numbers before putting it back together.

Did you measure bore and stroke?

Guy complaining to them about the fake 62cc saw showing his paper work from them with saw. He said 54cc. Guessing misprint?

So anyone measure one of their 6200 yet?

 

[Piotr Pakuła]

Marketing trick ;-)

 

[pbear]

Did you measure bore and stroke?

Guy complaining to them about the fake 62cc saw showing his paper work from them with saw. He said 54cc. Guessing misprint?

So anyone measure one of their 6200 yet?

View attachment 1071003

I have one, it’s new but after a little carb adjustment it runs fine. As to the size, my book also says 54, It’s considerably smaller than my Stihl MS 390 and it is definitely lighter. I’ll put it to the test this year cutting white birch and larch. I see the have discontinued the 6200 and now the same saw in looks is called a 5800. I’m not going to complain as it was $130 on eBay and for the money it appears to be a good midsize saw regardless of the displacement of the engine. I have only made one cut with it on a 20” birch log and it cut as I would expect.
I use to work in the woods and have run bigger saws and landing saws about the same size as the Neotec, time will tell.

 

[ijpom]

I have a BlueMax with the 45cc, but have never needed to pull it apart to see the differences.
But in trying to make two bad clones into one good clone, I recently pulled a scored 52cc p/c off and replaced it with a 46cc.


Bad 52cc cylinder with plain transfer.


Good 45cc cylinder with fin in transfer.

Anyone know if that transfer fin makes much of a difference?

Real question is:
Once I deleted gasket, and just used sealant, I have a 'squish' of 0.9mm or about 36/1000 of an inch. Compression feels good, but I'm not getting any firing from this new combo.
Anybody think the cylinder or increased compression is the issue?

 

[NSEric]

The ones with the fin/divider in the transfers run a little better.
There's some cylinders with tiny exhaust and intake ports tho, those dont run that good without doing some porting.
The increased compression wont cause it not to start. Check the basics, spark fuel, etc, then try pouring a little gas in the carb and see if it starts.

 

[Piotr Pakuła]

High compression suggests the use of a starter with a double spring because the usual one will fall apart too quickly