Flying Horse 80cc 2 Stroke Questions

[YetiWoodz]

Are shark heads or billet heads even better than 6cc fred heads?

 

[mark20]

No, there actually worse then the stock slant head (stock heads are around 6.5cc, most Chinese cnc heads are 8cc, aka low compression heads)
Id just pony up the extra 13$ or so and get a genuine fred head from crmachine or shave the stock head

You could also get a tomos hi compression head for 40$ shipped from treatland, you just need to drill out the bolt holes slightly

 

[YetiWoodz]

So the less cc for heads, the better?

 

[YetiWoodz]

Actually wouldn't the taller fins be better?, because how it works is increasing the surface area allows more heat transfer to cool the engine down

 

[mark20]

So the less cc for heads, the better?

Well, depends on the build, you want high enough compression that you get bottem end, there also very good for stock to midrange builds.
Higher cc heads are for more top end screamers as they can (technically) move more air at higher rpms

And yes, cnc heads are ment to cool motors, preformence is really a secondary benift.

First, clean up the ports and raise the exhuast duration to 165. See if you like it, if not

Get a pipe, then re jet the carb, and see if you like the preformence, if you want a bit more, get a 6cc head

 

[Chainlube]

The most economical way to raise compression is to plane down your own head, and add a thinner gasket.

 

[GreasyChris]

2 Stroke Tuners Handbook | PDF

All you ever wanted to know about performance tuning two stroke engines.

www.scribd.com

Everything you want and need to know is in this book. Bikeberry is in the business of selling parts and will tell you whatever you want to hear to sell those parts.

 

[Tyler6357]

The most economical way to raise compression is to plane down your own head, and add a thinner gasket.

Don't you mean to deck the cylinder? You don't want to mess with the head.

 

[Tyler6357]

I recommend getting a head with large cooling fins, these engines are air cooled and a large head with large fins will keep the engine temps down, which is the best thing you can do for the life of the engine.

 

[Frogslayer]

Decking the top of the jug or head will give you the same results. A smaller combustion chamber will give you higher compression that's why more power. I honestly think that these engines could run with no head fins if set up as a low power low compression reliable daily driver. If you're running so hot you need taller fins on your head you must be running lean and mean and if you're not racing you're just shortening engine life for fun or whatever. Order a temp gun and know what's going on. I ordered one for stuff like this and now i use it all the time for cooking as well.