SkyHawk Connecting Rod Question.
- Thread starter biknut
- Start date
Thanks for the reply. I guess I'm not crazy after all lol.
What about the cylinder. Are they special for SkyHawks? It looks like the overal legnth it the same. The intaks and exhaust ports look about the same, but it looks the transfer ports are a little lower?
Hey Biknut!
You are not crazy. These differences in the engines is driving me crazy too! I discovered that indeed the connecting rod and piston for this engine is different from all others I've seen. It is also reportedly different from the GT-5A and GT-5SR engines. The connecting rod of the GT-5 engine is longer than all the other engines, so to compensate, a different piston must accompany the GT-5 crankshaft assembly. If you go to Gasbike.net or Kings, you can see the piston for the GT-5A or GT-5SR "super rat" is the one which has the lower wrist pin location. The other piston they sell is for the "66cc engine"; pretty vague description, but you will notice that in the picture, the wrist pin location is higher. That is the piston for the GT-5 engine.
I'm still trying to get other parts for the GT-5 engine... namely, the cylinder body. So far.. no luck! I've been talking about this cylinder body having a unique transfer port design. The top edge of the transfer port has an angled shape, so when the piston begins to reveal the port, the incoming charge is directed more accurately towards the back of the cylinder. The results of my tests show this design to be superior, but I can't find the cylinders, unless I purchase a new engine.
This type of confusion seems to be common with all types of Chinese motors, including scooters.
-Fred
You are not crazy. These differences in the engines is driving me crazy too! I discovered that indeed the connecting rod and piston for this engine is different from all others I've seen. It is also reportedly different from the GT-5A and GT-5SR engines. The connecting rod of the GT-5 engine is longer than all the other engines, so to compensate, a different piston must accompany the GT-5 crankshaft assembly. If you go to Gasbike.net or Kings, you can see the piston for the GT-5A or GT-5SR "super rat" is the one which has the lower wrist pin location. The other piston they sell is for the "66cc engine"; pretty vague description, but you will notice that in the picture, the wrist pin location is higher. That is the piston for the GT-5 engine.
I'm still trying to get other parts for the GT-5 engine... namely, the cylinder body. So far.. no luck! I've been talking about this cylinder body having a unique transfer port design. The top edge of the transfer port has an angled shape, so when the piston begins to reveal the port, the incoming charge is directed more accurately towards the back of the cylinder. The results of my tests show this design to be superior, but I can't find the cylinders, unless I purchase a new engine.
This type of confusion seems to be common with all types of Chinese motors, including scooters.
-Fred
Thanks for the report. That confirms what I was finding out about the SkyHawk I was working on. I think Flying Horse motors have their own piston too.Hey Biknut!
You are not crazy. These differences in the engines is driving me crazy too! I discovered that indeed the connecting rod and piston for this engine is different from all others I've seen. It is also reportedly different from the GT-5A and GT-5SR engines. The connecting rod of the GT-5 engine is longer than all the other engines, so to compensate, a different piston must accompany the GT-5 crankshaft assembly. If you go to Gasbike.net or Kings, you can see the piston for the GT-5A or GT-5SR "super rat" is the one which has the lower wrist pin location. The other piston they sell is for the "66cc engine"; pretty vague description, but you will notice that in the picture, the wrist pin location is higher. That is the piston for the GT-5 engine.
I'm still trying to get other parts for the GT-5 engine... namely, the cylinder body. So far.. no luck! I've been talking about this cylinder body having a unique transfer port design. The top edge of the transfer port has an angled shape, so when the piston begins to reveal the port, the incoming charge is directed more accurately towards the back of the cylinder. The results of my tests show this design to be superior, but I can't find the cylinders, unless I purchase a new engine.
This type of confusion seems to be common with all types of Chinese motors, including scooters.
-Fred
GT-5 = SkyHawk, I guess.
I have both a GT5 and a GT5-a, the only discernable difference between them is the wider intake port (it's exactly the same as the exhaust port so gaskets are interchangable and port matching is already done). Otherwise I've been swapping parts between them for the last 8 months without issues, it wasnt until I bought a piston from a different vendor that I encountered the lower wrist pin.
