You're welcome dude. This site is about getting and sharing info. Good bunch of people here. Glad you got it started and now comes the fun part.
My first build and so many issues..
- Thread starter jeffyh
- Start date
Jeff,
All the rewards we want is to see you riding and enjoying your motorized bicycle. We'll stick with you until that happens. Good luck.
I just posted in your carburetor question thread and I hope it offers some help for you.
Tom
All the rewards we want is to see you riding and enjoying your motorized bicycle. We'll stick with you until that happens. Good luck.
I just posted in your carburetor question thread and I hope it offers some help for you.
Tom
Still trying to break it in. I maybe have 30 miles on it now...
So I'd like to pick your brains again if you don't mind... The GT6 kit I bought came with a high compression head. I didn't think anything of it until i saw the price since it seemed like extra work cause the motor came with the stock head mounted.
I've been reading a lot and can't figure out if high compression head "gains" are from placebo effect or from an actual boost in compression which I read aren't supposed to be that significant in these small engines.
Since I already have one, think it'd be worth putting one?
So I'd like to pick your brains again if you don't mind... The GT6 kit I bought came with a high compression head. I didn't think anything of it until i saw the price since it seemed like extra work cause the motor came with the stock head mounted.
I've been reading a lot and can't figure out if high compression head "gains" are from placebo effect or from an actual boost in compression which I read aren't supposed to be that significant in these small engines.
Since I already have one, think it'd be worth putting one?
Jeffy, I would suggest that you finish breaking in before you put on the high comp head. That way you'll find out what improvement it really makes. With only 30 miles on it you are still going to experience changes so probably best just to wait.
just my two cents, ride on
just my two cents, ride on
Combustion chamber shape gains are more significant than the actual compression ratio, especially in a 2 stroke and even more when you get around to to tuned pipe. The stock head has a terrible squish area. Squish is the area that is closest to the piston and is important for developing turbulence and increasing burn speed while fighting detonation.
Here is a corny sketch of how it works:
I modified my stock head to push the squish area out to the edge of the cylinder and have it match the piston.
The squish gap should be 0.5mm to 1.5mm, ideally 1mm.
The advantage of this shape is less detonation and heat regardless of the actual compression ratio.
Excuse the poor photo quality. Head on the right is the modified one.
Your Hi-Comp head should have this shape.
Check the squish gap with 1.5mm lead electronics solder. Rosin core is OK.
Solid mount the engine. I have been through this with motorcycles and quads.
The more points of contact the better.
Get a better air filter. Right now.
I have only 300 or so miles on my China Girl and just discovered dirt is getting past the stock air filter and scoring the cylinder.
Steve
Here is a corny sketch of how it works:
I modified my stock head to push the squish area out to the edge of the cylinder and have it match the piston.
The squish gap should be 0.5mm to 1.5mm, ideally 1mm.
The advantage of this shape is less detonation and heat regardless of the actual compression ratio.
Excuse the poor photo quality. Head on the right is the modified one.
Your Hi-Comp head should have this shape.
Check the squish gap with 1.5mm lead electronics solder. Rosin core is OK.
Solid mount the engine. I have been through this with motorcycles and quads.
The more points of contact the better.
Get a better air filter. Right now.
I have only 300 or so miles on my China Girl and just discovered dirt is getting past the stock air filter and scoring the cylinder.
Steve
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