Had a 79cc Predator for about 2 hrs.
It had hardly any comp.
I took off the V cover & found that the rockers were not even close to being centered over the valve stems, & could not be massaged either,, to get them lined up better.
I closed it up & took it right back.
That valve train is a joke on those, & ''very'' weak. Sorry to say that,, but I tell it like it is.
Found a GX-200 for a great deal,, & that was the best thing I ever did for that bike.
Even did a whole bunch of mods & custom jack shaft assy. on the MM-80cc ''Lifan'' set up, before the Honda engine,, just to see if it could pull some one 210 lbs. decent.
It did, but is ''nothing'' like the stage 1 - 196cc set up that's in it now.
Honda's are expensive but well worth ''every'' penny,, & will last pretty much the life of the chassis of the bike & then some,, if you take care of them,, even if you don't....
The Honda's are made in a Honda factory in Singapore, with Japanese tooling ect. ,, ''not'' China.
I have seen GX -200's on asphalt tampers, that were completely beat to shit looking,, but ran like a champ.
You could tell that they had fallen out of trucks before ect. & are ''very'' abused,, but still fire right up.
The 120cc & 160cc ones, either GC or GX ,, would even be a night & day improvement.
Like the posts above stating,, you could probably find one of those engines on a press. washer ect. in a pawn shop ect.,, for penny's on the dollar.
It's a no brainer, & I wouldn't even waste the money on a jack shaft set up.
I was ''very'' lucky to sell my jackshaft set up, for about what I had in it.
Guys on here pretty much told me I was ''nuts'' for doing all the mods on the little 80cc,, ''they were right'',, even though I pulled it off better than most thought possible.
My 2 cents.
P/S,,
High quality # 35 chain is even good on the big engines.
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