Author Topic: Redmax 621  (Read 8198 times)

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Offline Chris-PA

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Re: Redmax 621
« Reply #20 on: May 27, 2015, 08:11:25 pm »
Thanks. 

BTW, there was some discussion about the G621 being heavy in early posts upthread - my clone is 12.4lb, and it is slightly heavier than the real one. 

Offline 660magnum

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Re: Redmax 621
« Reply #21 on: May 27, 2015, 09:08:37 pm »
My 6.2 is actually Zenoah G62 model airplane engine. The most common part about it and the 6.2 chainsaw is the cylinder and piston.

That Chinese company made G62 model airplane engine clones too for a very short while. I've seen pictures and for sale ads but never a actual clone engine.
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Offline nenicu

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Re: Redmax 621
« Reply #22 on: July 26, 2015, 11:59:06 am »
 Hello boys. I have a Zenoah 621 i want to port. Anybody has some pics of a ported cylinder and piston? Thanks!

Offline 660magnum

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Re: Redmax 621
« Reply #23 on: July 26, 2015, 12:46:17 pm »
IIRC the 621 is a open port engine?
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Offline Cut4fun .

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Re: Redmax 621
« Reply #24 on: July 26, 2015, 04:43:48 pm »
@EHP used to port them. So you might ask him about them.

Offline Chris-PA

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Re: Redmax 621
« Reply #25 on: July 28, 2015, 12:39:53 pm »
I have not yet seen a real G621 cylinder, but my clone was open port.  The Chinese usually do not change the designs unless they have to, and anyway Zenoah sells both a G621 and aG6200, and I suspect the G6200 is the same as my clone. 

My clone required only some work to the intake port and a gasket delete (and muffler mod) - cutting the base would have been better yet but I was lazy.  I ended up at 0.035" squish, but the piston is domed and the combustion chamber is very small, so I suspect compression is pretty good anyway (I have no gauge but it feels healthy).  It runs very well.

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Re: Redmax 621
« Reply #26 on: July 28, 2015, 01:46:20 pm »
Looks like my Zenoah G62 which has a Husqvarna labeled cylinder on it
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Offline Cut4fun .

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Re: Redmax 621
« Reply #27 on: July 30, 2015, 10:07:39 am »
@Chris-PA  here is a oem redmax 621 cylinder to compare in pics.




Offline Chris-PA

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Re: Redmax 621
« Reply #28 on: July 31, 2015, 08:31:24 am »
Looks identical, just a cleaner casting.  I know it's an open transfer cylinder, but it sure does run well. 

Offline EHP

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Re: Redmax 621
« Reply #29 on: August 01, 2015, 10:42:41 am »
the 621 takes well to porting just remember to port more for torque than rpms , its a cheap motor but you will be surprised at how much power you pick up , Donot go wild on porting as you can over port these jugs pretty quick . You want your max power at 10,500 or so , they are not a cookie cutter but once ported they sure will cut cookies or firewood for a long time

 

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