Athena 70cc piston port install. base gasket height? timing??

Hey guys.

Just jumped on an Athena 70cc piston port kit, and I'm at a juncture...

I have a '78 Maxi S thats stock than a 14mm bing with about 600 original miles on it that its gonna go on but here's my dilemma... I also have another e50 bottom end that i just picked up that's all cleaned out and ready to be case matched. I don't want to end up with a crazy setup in the end, I want an upgraded daily as I ride her to work everyday in town. So my question is do I need to take the time to case match and build out a bottom end with an upgraded crank and clutch with this kit or can i save that other case i have for something even crazier...

Parts list ive got coming:

-Athena 70cc piston port kit

-puch 70cc hi compression head - old style fins (slightly less compression than hi i guess)

-grandpas 15mm intake

-60s and 70s jets

- jammy pipe (and centerstand spacer)

-foam filter

- metrakit 65cc gasket kit (to get base height right)

-BH7s plugs

Also my biggest concerns are getting the squish and timing right here and i'm not super well versed doing either.

Re: Athena 70cc piston port install. base gasket height? timing??

Don't worry about case matching it's more to get an extra 5% out of a build imho

Just time it to ~14-16° and make sure the jetting is ok.

The kit is spaced right when the exhaust port is just open at bdc and your squish is about 1mm.

What can kill e50s is when you start hating your low end power so you start to go nuts with clutch springs and engagement, stock you'll be fine

Re: Athena 70cc piston port install. base gasket height? timing??

thanks wormdirt! that pretty much answers all of my questions, and I'm not expecting to wheelie out of the hole so should be good haha. any good tutorials or videos on timing you recommend?

Re: Athena 70cc piston port install. base gasket height? timing??

Travis tutorial has a good one on YouTube, just search the forums there are a ton of write ups on it. I finally bought a timing tool from treatland a few months ago and it is amazing. Don't know why I spent years doing it the hard way

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