Hello, first time posting here, and apologize as I am sure some of the questions I am about to ask have been asked before..
I have built 3 different China girl kits (as I am seeing them referred to here) on three different bike styles, the one where you buy the whole kit and essentially bolt it on.
I have grown tired of that and wanted something more mechanically challenging and a little more fun to ride.
I have a very sturdy cruiser frame bike that I purchased a couple years back and I just bought a 79cc Predator engine from Harbor Freight and have it pretty much ready to mount.
Here is where I am having trouble.. I see parts all over to build the 212cc but am not seeing much available for the 79cc.
I have looked at YouTube and here, and have seen many similar builds but am finding a lack of parts data for the 79 (example: I've heard that the pto shaft is 5/8th bore according to the specs, but I am seeing people in forums say it is fact actually 16mm bore), so do I look for a 5/8 or a 16mm bore centrifugal clutch and sprocket pulley?
Also I am having a really hard time finding any sort of mounting plate for the 79cc, for the 212 I am finding all over the place, I can weld, and wouldn't mind fabricating a mount between the bottom tube and seat post tube, but wanted to make absolutely sure ahead of time that there wasn't a bolt on type plate.
My second question is: I know the bike chain is going to be too weak to withstand the torque of the new engine, and will need to get a couple HD chains coming to the jackshaft, and output from the jackshaft to the rear sprocket..
But Will the existing sprocket I have mounted on the bike be able to withstand that new torque?
Finally, would you recommend a centrifugal clutch with chain sprocket attached and a jackshaft as separate mounted pieces? or, a belt driven torque converter/jack shaft combo and only have a single HD chain from the output of the jackshaft to the rear sprocket? (I am not even sure they make Torque converter jackshaft combos for the 79cc 5/8 or 16mm pto shaft as I haven't had any luck finding one?? Do they?)
Again I apologize as I am sure all this information is here on these forums I just am very new to here so do not quite know how to navigate to all the pieces of information that will help me do this build. If anyone would be kind enough to point to the right thread or maybe a link to websites that sells various parts that are compatible with the 79cc Predator Engine!
Thank you very much.
I have built 3 different China girl kits (as I am seeing them referred to here) on three different bike styles, the one where you buy the whole kit and essentially bolt it on.
I have grown tired of that and wanted something more mechanically challenging and a little more fun to ride.
I have a very sturdy cruiser frame bike that I purchased a couple years back and I just bought a 79cc Predator engine from Harbor Freight and have it pretty much ready to mount.
Here is where I am having trouble.. I see parts all over to build the 212cc but am not seeing much available for the 79cc.
I have looked at YouTube and here, and have seen many similar builds but am finding a lack of parts data for the 79 (example: I've heard that the pto shaft is 5/8th bore according to the specs, but I am seeing people in forums say it is fact actually 16mm bore), so do I look for a 5/8 or a 16mm bore centrifugal clutch and sprocket pulley?
Also I am having a really hard time finding any sort of mounting plate for the 79cc, for the 212 I am finding all over the place, I can weld, and wouldn't mind fabricating a mount between the bottom tube and seat post tube, but wanted to make absolutely sure ahead of time that there wasn't a bolt on type plate.
My second question is: I know the bike chain is going to be too weak to withstand the torque of the new engine, and will need to get a couple HD chains coming to the jackshaft, and output from the jackshaft to the rear sprocket..
But Will the existing sprocket I have mounted on the bike be able to withstand that new torque?
Finally, would you recommend a centrifugal clutch with chain sprocket attached and a jackshaft as separate mounted pieces? or, a belt driven torque converter/jack shaft combo and only have a single HD chain from the output of the jackshaft to the rear sprocket? (I am not even sure they make Torque converter jackshaft combos for the 79cc 5/8 or 16mm pto shaft as I haven't had any luck finding one?? Do they?)
Again I apologize as I am sure all this information is here on these forums I just am very new to here so do not quite know how to navigate to all the pieces of information that will help me do this build. If anyone would be kind enough to point to the right thread or maybe a link to websites that sells various parts that are compatible with the 79cc Predator Engine!
Thank you very much.
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