About to make my orders for first build, just a few questions.

junglepig said:
Thanks for the link to the video. The manual with my kit says A-80, and the listing gave those same specs. Unfortunately, I did not pull the jug before installation, so I missed the opportunity to identify the piston and rod variant because I did not know that I would want to know this, lol. No doubt I will have to go in now and find out for sure.
Can you tell from these photos if my engine is consistent with the "A-80" designation?
I've almost learned enough now to be dangerous and want to go ahead and clean up the ports and match them a little. They sure are ugly as they came cast from the factory!
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It does appear to be! very rough castings on that cylinder body.
 
Tyler6357 said:
Fred from CR Machine is the best. He has done quite a bit for our hobby and everyone has been copying his stuff for years. His stuff is expensive but he won't rip you off and it will be high quality.--->https://www.crmachine.com/
When you have some time you should watch some of his other videos on youtube they are very informative.---> https://www.youtube.com/user/turrettooling1968/videos
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Yeah man i heard of him saw some sick a.. Bikes he made or at least i think its the same fred
 
Tyler6357 said:
He was the first person to design a high compression head for china girl engines which he dubbed "The Fred Head". It wasn't long before everyone was selling a copy of his design.
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Fred is a friend and good guy,set in his way's and didn't patten protect or copyright his product not that it would have stopped the Chinese.There is a mis conseption about the compression being higher though,his first head was a 7cc chamber and if you had one of the original engines they had 8-10cc heads so yes it was an improvement.Somewhere around 08 they started to all be 6cc and so the 7cc Fred Head was no longer higher comp and as the copies came out most were 8cc so again even less comp,now there are 8-7 and some true 6cc after market heads and Fred will make any cc you want if he trust's you LOL.
 
Street Ryderz said:
Fred is a friend and good guy,set in his way's and didn't patten protect or copyright his product not that it would have stopped the Chinese.There is a mis conseption about the compression being higher though,his first head was a 7cc chamber and if you had one of the original engines they had 8-10cc heads so yes it was an improvement.Somewhere around 08 they started to all be 6cc and so the 7cc Fred Head was no longer higher comp and as the copies came out most were 8cc so again even less comp,now there are 8-7 and some true 6cc after market heads and Fred will make any cc you want if he trust's you LOL.
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Oh, that's interesting, I didn't know that. I didn't really get into motor bicycles until 2010. A few years later I did buy a real FredHead from his website that is marked as 6cc, it cost me $69. Later, I also purchased a Fred Head copy on e-bay for $40 advertised as 6cc. I couldn't tell the difference just looking at them, they looked identical but I didn't measure them. The only difference I could see was that the copy had super sharp fins like razor blades, they had to be filed down just to hold it without slicing up my fingers.
 
Street Ryderz said:
It does appear to be! very rough castings on that cylinder body.
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Another question on engine designations. I took my jug off today so I could verify which rod and piston I have, and I cleaned up the transfer port exits while it was off.

I found the type B piston with a long rod, marked "ZAE80."

In one of Fred's videos explaining engine geometry from 3 years ago, the ZAE80 rod did not make an appearance, and the "A-80" engine was described as having a different rod, "ZL" I think.
He showed a ZAF80 rod as belonging to the GT-5 type.
According to BicycleMotorWorks, it appears that ZEDA80 – ZL 40MM – ZAE60 – ZAE80 – ZAF80 – FM80 marked rods are all long rods for either ZEDA80 or GT-5 engines.

So, I'm pretty sure I have either an A-80 with 40mm stroke and long rod. (It was spec'd as such on the eBay listing, but I doubt that means anything.)
Or, could it be a GT-5 or ZEDA80 type with 38mm stroke?

In 2018, what's the best way to tell the difference? And, as far as I can tell, the jugs that come from China are all ported alike? or no?
That is, do I need to know what my geometry is if I needed to order a new cylinder for it?

Sorry I got so wordy. And thanks for any help!
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junglepig said:
Another question on engine designations. I took my jug off today so I could verify which rod and piston I have, and I cleaned up the transfer port exits while it was off.

I found the type B piston with a long rod, marked "ZAE80."

In one of Fred's videos explaining engine geometry from 3 years ago, the ZAE80 rod did not make an appearance, and the "A-80" engine was described as having a different rod, "ZL" I think.
He showed a ZAF80 rod as belonging to the GT-5 type.
According to BicycleMotorWorks, it appears that ZEDA80 – ZL 40MM – ZAE60 – ZAE80 – ZAF80 – FM80 marked rods are all long rods for either ZEDA80 or GT-5 engines.

So, I'm pretty sure I have either an A-80 with 40mm stroke and long rod. (It was spec'd as such on the eBay listing, but I doubt that means anything.)
Or, could it be a GT-5 or ZEDA80 type with 38mm stroke?

In 2018, what's the best way to tell the difference? And, as far as I can tell, the jugs that come from China are all ported alike? or no?
That is, do I need to know what my geometry is if I needed to order a new cylinder for it?

Sorry I got so wordy. And thanks for any help!
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The ZAE 80 is a long rod but used on gt5 type engines with 38mm stroke,An A80 uses the ZL long rod and 40mm stroke same geometry as Zeda but the castings are slightly different.The Zeda's cases have larger bearing bosses for crank and the transfers window is misplaced in relation to the track.All the cylinders have simular port timming and can be interchanged if need be.The only rods used in Zeda engine have been the Zeda 80 witch is actualy a 39.5mm stroke and the ZL 40mm that they first used you wont find any of the other long rods used in anything other than the gt5 type with 38mm stroke unless it was changed after the fact by the end user.
 
Street Ryderz said:
The ZAE 80 is a long rod but used on gt5 type engines with 38mm stroke,An A80 uses the ZL long rod and 40mm stroke same geometry as Zeda but the castings are slightly different.The Zeda's cases have larger bearing bosses for crank and the transfers window is misplaced in relation to the track.All the cylinders have simular port timming and can be interchanged if need be.The only rods used in Zeda engine have been the Zeda 80 witch is actualy a 39.5mm stroke and the ZL 40mm that they first used you wont find any of the other long rods used in anything other than the gt5 type with 38mm stroke unless it was changed after the fact by the end user.
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So, ZAE80 rod means = GT-5 and 38mm stroke crank, is that correct?
(The only contrary info I have is that the eBay listing said 40mm stroke, and it came with an A-80 manual.)
Thank you!
 
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