Need help

[jbburns99]

I just bought a 66 cc chinese no name engine. seems like the standard one i've been seeing all over the web. I am completely new to motored bikes and i live in Denver. I need help deciding what parts to replace from the stock kit to compensate for the high altitude, and where to find these parts. I've been looking at new carbs so far but am at a lost as to which one would best work with my engine. Any help is appreciated, i apologize for lack of knowledge in advance

 

[crassius]

I'd say that kind of tuning should be left till all is working well otherwise. Should only require a bit of playing with the main jet.

 

[Deleted member 12676]

the bare essentials costs just a few dollars; replace the upper connecting rod bearing and plane the head and top of the cylinder using glass and sandpaper. Plane the hell out of it to remove at least 1mm to increase compression (which also goes down at high altitude). Don't be surprised if you need to take off 2mm. Hard on the arms though. Take 2 days to do it unless you have gorilla arms. Drop the needle to lean out the mixture. After getting used to it then plan on getting a real carb. That topic is addressed on my site.

 

[bluegoatwoods]

I'm no expert on matters like this. But I'd say that, at the moment, you don't need to worry about mods for altitude.

Start by building your bike. And read as much as you can among these threads so that you avoid those pitfalls that have nothing to do with altitude. Things like chain tensioner, fenders, motor mounts, stuff like that.

Once you've got your bike assembled properly, then you might want to lean out your fuel mixture. Not hard.

 

[Deleted member 12676]

I disagree. High altitude robs a lot of power. Mods for it are of primary concern, mostly increasing compression and changing jetting.