Cylinder head

[Whitewill1412]

Has anyone used one of these heads? Is it higher compression? How does it handle heat? As for the banana pipe. I haven't read anything good about them. Is it actually a muffler or just a pipe? Does it hurt performance?

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[DieselTech]

Has anyone used one of these heads? Is it higher compression? How does it handle heat? As for the banana pipe. I haven't read anything good about them. Is it actually a muffler or just a pipe? Does it hurt performance?

CNC Red Cylinder Head Cover&Muffler Exhaust Piep For 66cc 80cc Motorized Bicycle | eBay

1xMuffler Exhaust. 1xCylinder Head Cover. 1xspark plug. Size: As Picture. 1xClutch Lever.

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I would not myself purchase that cylinder head, there is not much cooling surface area on that type of cylinder head. Yes if you use a hi-compression cylinder head & set squish gap correctly it should increase power over the stock cylinder head. I dont recommend the banana pipe either. This is just my opinion.

 

[Chainlube]

I would not myself purchase that cylinder head, there is not much cooling surface area on that type of cylinder head. Yes if you use a hi-compression cylinder head & set squish gap correctly it should increase power over the stock cylinder head. I dont recommend the banana pipe either. This is just my opinion.

Thanks, you saved me from typing some .

 

[Chainlube]

For 10 bux more and a little labor polishing it, this is better.

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[Whitewill1412]

For 10 bux more and a little labor polishing it, this is better.

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What do you use to polish it?

 

[Chainlube]

What do you use to polish it?

Some sandpaper. Take off the rough stuff with 100/120-ish grit and then go finer up to 420. Just the squish band, the mating surface you'll want to keep that flat so put the sheet of sandpaper on a sheet of glass or mirror.

 

[Chainlube]

One other thing, compare the crown on your piston to the concave of the squish band, they should be close.

 

[Whitewill1412]

Some sandpaper. Take off the rough stuff with 100/120-ish grit and then go finer up to 420. Just the squish band, the mating surface you'll want to keep that flat so put the sheet of sandpaper on a sheet of glass or mirror.

Ok. I was thinking some kind of dremel bit, but that might do more damage than good.

 

[Chainlube]

Ok. I was thinking some kind of dremel bit, but that might do more damage than good.

Scotch brite pads work too, at the end.
If you want to do the combustion chamber, then a small ball hone is best and takes less effort.
@ImpulseRocket89 just did one, maybe he has some other pointers?

 

[ImpulseRocket]

Scotch brite pads work too, at the end.
If you want to do the combustion chamber, then a small ball hone is best and takes less effort.
@ImpulseRocket89 just did one, maybe he has some other pointers?

A rotary tool and scotch brite bits followed up with polishing pads and compounds. Then a bit of patience and willingness to get dirty lol.

I used these specific ones as they go up to "1000" grit. I then did 3 stages of polishing compound with cotton buffer pads.

https://www.amazon.com/Abrasive-Rocaris-Buffing-Polishing-Shank%EF%BC%8CPolishing/dp/B091DLSBWC/ref=sr_1_4?crid=3CQ9V8OSRPS69&keywords=scotch+brite+rotary+tool&qid=1671815814&sprefix=scotchbrite+rotary+tool%2Caps%2C122&sr=8-4

Turned out looking ok.


I then did as previously described by doing the flange surface on a piece of glass with increasing grits of sand paper. I only did up to 400 grit, which is more than enough. You can keep going up in grit if so desired. I recommend doing this part last if you use a rotary tool, as you can see evidence in the previous photo of me having a few disagreements with the flange surface and the buffing wheels more than a few times.