Tips I've learned from many builds-great newbie read.

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Thanx again guys! I do have a metering cup, so it's not that difficult. For the 1 gallon I have left that's mixed 16:1, I added 4 oz of gasoline to be on the safe side. Plan on doing 20-24:1 in the future if I buy a good synthetic. My crazy Iranian mechanic advised against Castor Oil because of damage it could do to the reed valves if it separates from the rest of the mix. Guess that I will buy a good synthetic 2 stroke oil mix-Gearhead
 
Unless you are a racing fuel chemist, don't mix up your own "special blend".
I am using this right now:
http://www.maximausa.com/shopping/index.php?main_page=product_info&cPath=2&products_id=15

It doesn't take a chemist to mix castor and synthetic...its not rocket science. For many years I made my own glow fuel from scratch to get what I considered an ideal model airplane fuel... It consisted of methanol, nitromethane, synthetic and castor oil, and 1/2 squirt per gallon of a silicon additive for antifoaming.
 
There are no reed valves in these cheap engines (no exhaust power valve either).
Do not let your crazy mechanic mislead you into thinking that these engines are actually that technologically advanced. Castor oil at best (or worst) might leave more carbon buildup in the combustion chamber when compared to a modern synthetic or semi-synthetic pre-mix.
Is does however smell alot better than modern oils when burned.
 
That is WILD! How the heck does the engine cut off the intake of fuel/air when it's compressing and how does it expel the exhaust gases with no compression loss? Is it a cutout in the piston? Very simple!:)-Gearhead
 
It uses big holes in the sides of the cylinder called ports. They get uncovered and covered as the piston moves up and down.
 
This is a good read for those that want to learn more:
http://scoot.net/faq/2-stroke

The engine discussed is quite similar to an HT engine.
HT's do not have a reed valve like the one shown, they are piston port intakes.

Edit: found the link I was looking for...
 
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great list for a pro build. i would like to find a list with only the important stuff to get these skyhawk 48s together fast and running well
 
great list for a pro build. i would like to find a list with only the important stuff to get these skyhawk 48s together fast and running well

Its all important stuff. I wouldn't have made this post if i didn't think it was important for newbies who want to learn from other's problems and not have to reinvent the wheel. Built it fast and it won't last. Trust me, nothing worse than having repeated failures on your first several rides. Don't believe me, look at all of the newbie posts about loose heads, exhausts that fall off, no start conditions, chains that are thrown, electrical issues, and tons of other stuff. If you only plan on putzing around the block, just follow the manufactuer's instructions and you'll at least be within pedaling distance from home.

My suggestions are for reliability and reliability is something that most folks value. I have been 15+ miles from home and have had a failure such as a bad China spark plug fail internally or a gas tank inline petcock filter get clogged from the rust in the tank, chain thrown because alignment was not perfect or chain stretched too much, or piston ring pin that prevents ring from catching a port pop out causing engine failure..



PS I have no trouble taking any of my bikes 2-3 hours into the Rocky mountain wilderness and not having to worry about engine failure or other mechanical failure..trust me, I've had it all happened with our crappy HT engines and don't want others to experience similar build issues While pulling the head may be overkill, trust me. The engines vibrate quite a bit causing the head studs to back out. When a newbie sees a head gasket leak they may automatically crank down on the head studs to tighten the loose head. Problem is that if the studs back out, there is less thread holding the torque of the nut, eventually there arises a point where the stud pulls out and takes the thread with it. Using upgraded studs and loctiting them prevents this very common problem from occurring (usually this happens in 1st 100 miles or so). I, in fact, JB weld my replacement head studs into the block and ride worry free...a little overkill but I've had even my loctite recommendation fail on me.
 
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