ported cylinder

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fischer550

Member
Mar 24, 2014
234
0
16
Fort Collins, CO
I have a bottom end and piston from thatsdax, and technically it is a 69cc not 66cc. There is a ported cylinder on ebay I want to buy, but it's for 66cc. Will it work?
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Technically I think its a 68.5cc which we still call 66cc yes the jug will work, make sure it actually has port work done to it, there are some on there that claim there has been port work done but in fact they are just plain untouched. 66cc jugs.

With a cheapy rotary tool ( dremel clone ) or actual dremel, you can clean the intake and exhaust port of any casting that is in the port in just a few minutes, if you dont know much more about how things work I would suggest only doing that mod and put it together right and you'll likely have a good running engine if you tune the carb properly and use an exhaust that isn't to restrictive.

Map
.wee.
 

rogergendron1

New Member
Sep 18, 2013
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woburn ma
I sexond just buying a 30 $ blue hawk dremal clone and do the port work yourself to your exsisting jug .. Its a lot easyer than you think


Gring down the floor of the intake a little and round it out and then widen it
Now round out the floor and roof of the exhaust port and widen it
Now port match the intake and exhaust and your done .....

You only have to grind a little bit away and simply clean them up after and then match your intake and ezhaust as best u can .... A 70$ ported jug wil do didly squat if you just slap ot on a bike a bike and do not bother port matching the intake and exhaust anyway, lol so you stil need that dremal !!! Might as well just use to make your own ported jug !!
 

fischer550

Member
Mar 24, 2014
234
0
16
Fort Collins, CO
To be honest, I have never done any port work and I really don't want to mess it up, and I need a new cylinder anyways because I only bought the bottom end from dax, not the top so I figured why not just buy the ported one.
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
To be honest, I have never done any port work and I really don't want to mess it up, and I need a new cylinder anyways because I only bought the bottom end from dax, not the top so I figured why not just buy the ported one.
Why don't you just get the upper cylinder kit from Dax?

It will include gaskets and everything you need to build the engine.

Here's a link below for a parts kits, don't be mislead by ported Cylinder if the price is way high, not sure who you plan to buy from, but I can clean the ports up in about 10-15 or less on a jug if that is all that has been done to it, just knock the burs off and hit the inside of the ports with a drum sander on my dremel and bam.... she is cleaned up and has had some simple port work done that will improve the flow a bit.

You will need all of the parts in this kit inorder to complete the engine and this is a darn good price, I have bought from this guy for several years and never a single issue.

http://www.ebay.com/itm/66cc-Motorized-GAS-ENGINE-80cc-top-end-8mm-/191036700418


Map
 

Theon

New Member
Jan 20, 2014
1,440
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FNQ Australia
Just be sure for that price that they are starting with a large port barrel,
They usually have a 40mm inlet spacing and much larger exhaust flange.
If it is the large port and well cleaned up it is probably worth that.
The A80 barrels such as on the BGF site have much smaller ports and the timing can be all over the place.
 

maniac57

Old, Fat, and still faster than you
Oct 8, 2011
4,484
22
0
memphis Tn
Be wary of "ported" cylinders...never seen one yet worth a dime more than stock except from Arrow and CR machine.
You get whatever you get with ebay....
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
I see that arrow has a ported cylinder for the same price 69.99, I will get that one.
Jakes also has one that I'd be confident in running, Arrow has a good reputation so Im sure it will be good also.

Might even consider some good copper gaskets from www.juicemotoparts.com

Put a thin coat of silver spray paint on them let it dry and you'll have some gaskets you can use over and over.

Best wishes.
Map
 

fischer550

Member
Mar 24, 2014
234
0
16
Fort Collins, CO
Actually I might go with the ported cylinder and the reed kit from arrow, it says the cylinders will fit 66cc sky hawk engines. Will it fit the bottom end from dax?
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Actually I might go with the ported cylinder and the reed kit from arrow, it says the cylinders will fit 66cc sky hawk engines. Will it fit the bottom end from dax?
There has to be special work done to the cylinder jug for running reeds, if you dont have tools for porting a jug then ots for sure you wont be able to modify the jug for using reed valve set up.

Keep it sime and just put it together right and you be ok, dont get in over your head and spend money on things you cant make work.

I have bikes that have hit 46mph running an NT carb and pulling me at 215+lbs no reed s and just a well tuned and set up dax lower with a standard jug that I did a little port work to, the way I have ot set up right now it cruises for miles and miles at 43+mph if I want.

Since you're new to all of this, just keep it sime and learn to solve the issues you will encounter even then and then in timeyou can always change some things and do some upgrades if you want.

This is what I recommend, but its your money.... shrug. !

Map
 

sub66

New Member
Apr 25, 2014
140
0
0
canada
well im confused. are any port figures available for customers? is arrow going to help u w a pipe and teach u how to get 6400 rpm out of a 24mm carb like they do now?
what about the entertainer? does he send stickers?
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
well im confused. are any port figures available for customers? is arrow going to help u w a pipe and teach u how to get 6400 rpm out of a 24mm carb like they do now?
what about the entertainer? does he send stickers?
What is your point here?

Arrow is a known and proven winner with what they build, not sure if they give many pointers, but may offer a couple.

6400 RPM is chicken scratch, I've got 8000 - 9000 RPM out of mine...LOL

Jake sells stickers.

Map
.wee.
 

Davezilla

New Member
Mar 15, 2014
2,705
10
0
San Antonio Texas
That combo will work good, I really like the Dax bottom ends and Fred's heads, I do my own porting so I can't say how Fred's or Arrow's jugs are, but they are both reputable and know thier stuff.
You'll be happy with the way that combo runs and performs.