Did they produce a compression release head?

I swear I saw a picture of a leetle compression release gizmo valve in a head....is there one for the 70cc china chick engine?

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I had an old 360cc Yamaha endoro way back in the 70s that had this. It also had two sparkplugs over the one piston so that you always had a spair spark plug. If you did not use the compression release and that motor "kicked back", you could lose your leg.
For our "china chick" engines, you would have to make it yourself but why?

When I rig mine with the super Chinese grandma hill climber gears, the beast is a bear to start with pedals. Man it feels like an 800cc single cylinder with 16:1 CR!

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I would have thought that the larger sprocket would make it easier but we will agree to agree.
You could do it IF you found a spot on the head that would allow you to drill a hole and tap it for the valves threads. Would I do it? No.

With a front freewheel whatever ratio makes it "easier" for the engine to spin really fast and have lots of torque, i.e. tiny engine sprocket driving a much larger sprocket - will make it much harder to pedal start for the operator - it's the same direction as the engine - just now the rider has tall gears to fight against (but the engine will turn over at higher RPM!!).

I'm for sure not going to do it unless I find a bolt on head. I just won't be running the ultra granny ratio that often. This is not a problem with the standard jackshaft ratio or the highspeed ratio.

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If you have a friend who has a heliarc you can weld up an area on the head then machine it to mount the comp. release. Lot of work but it can be done you will maybe need to resurface the head as it might warp.

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Pablo are you guys still running the freewheel sprocket in the back? If so weld it to stop the freewheel and you should get the ease of starting back up. With the Schwinn I bought that had the free wheel crank the rear gears are fixed. When I put it on my other bike and the rear is free wheeled also when you coast nothing moves not rear gear no crank and of course my feet. So yes its going to be all up to your thighs to start it and with the extra gears Im sure its not an easy deal. At least if you weld the rear gear to the bearing and make it fixed you can go back to pretty much the old way of starting.
Well at least ya can get a nice hill to coast down and fire up with out killing yourself.
Terry (needs a jackshaft) Jonz

It doesn't work that way. Think about it. It still freewheels, even if we "weld" the rear freewheel.

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Ok Im confused on your problem then. I thought you were wanting to have the ease of start like we do normally with the gear on the left side. When you run a front free wheel and a rear free wheel you have to constanly pedal to be able to start the motor so if your going down a hill and you want to start the motor you have to pedal to start it because there is no movement of any of the drive line. If you have a fixed rear gear then when your going down that same hill you have movement of the drive line your pedals are not moving but everything else is just like it normally would if you are running a regular setup. Then you can just pop the clutch and go.
The schwinn system was made so that the rider could change gears when they were not pedaling with the fixed rear gear because the chain line was still moving but the rider didnt have to pedal.
So by welding the rear we just fliped the system that we use now. So with your setup and a fixed rear gear when you just push the bike the rear gear moves with the wheel it turns the crank and turns the jackshaft and motor just like it does on any other happy time setup. With the two free wheels that you have now its like turning over a model t.

You are correct that if you lock the rear freewheel it will turn the front chainring and assist in starting. The problem is that because in coast mode, rear wheel driving the chainring, as soon as you put a load on it, release the clutch, it will just unwind you rear derailleur and your chain will fall off. On your front freewheel system try riding the bike and put some friction on your front chainring with your foot and you will see what I mean.

Pablo is just having a problem because I screwed up and made an incorrect assumption. He caught my error and things should be good to go once he gets the new sprocket.