atc 70 big bore

[Crazyktmmatt]

Was surfing the web and came up with a cheap 88cc kit with a cam for a 70.


Anyone see or use this one? Or its it junk?


http://www.motoparthub.com/411_HXR_5411_BBR_88cc_Ftp_Big_Bore_Piston_Kit

[shortline10]

A flat top piston isn't much of an upgrade and I don't believe that cam will work in a atc head .

[Daddio]

Check this place out. They have lots of parts and info for the 70s.
http://www.dratv.com/index.html

[Frankencelery]

Never heard of that company. That doesn't mean they're bad, but I agree with Daddio. I would buy from DrATV. I don't know if you're going to get it that cheaply from them, but they've been serving our needs for a long time.

[Crazyktmmatt]

I was mostly curious. I did like the idea of a flat top piston. Didnt want a huge amount of compression, plus the kid can still start it.
Dratv wont email me back either on how a compression ratio.

[Frankencelery]

Yeah, I think Dratv must be a one or two-man operation, and you won't get super-fast email response from them. I just had a conversation with them about something similar. I had purchased a head on Ebay that said it was for an ATC70, but it wasn't, and the combustion chamber was much smaller. My piston was hitting the head. Since I waited too long to try to install it, I ended up having to eat it. Anyway, I finally contacted Dratv to ask what piston would work with this head, and they got back to me in about 24 hours with a recommendation. I bought the piston from them, now I just need time to see if it's going to work.

[Crazyktmmatt]

Ended up buying a dratv one on ebay.

Has any one played with porting a 70 head? Does it make a real difference?