Re-jetting Your Carb, As Easy As 1,2,3 ( quarkdude )

M

Mogyver69

Guest
Hello Mogyver69,
I checked the site again to make sure I didn't post something we couldn't reference: http://www.ehobbytools.com/en-us/dept_8.html
This site uses the drill# which also has a decimal equivalent. Most of the kits on that site have the drill sizes we need so it is a good reference. A good kit for us would be one that has Drill#65 to Drill#78 or so. The decimal equivalent of a Drill#65 is 0.0350 and the Drill#78 is 0.0160. Most of the carb jets I have redone on these Chinese 80cc carbs start out around 0.030 and you go up or down from there as you know. I would guess that if you were to drill your jet ( I know you already filed it ) it would be good to step it up 1000ths of an inch at a time. Using Drill#68(0.310) do a test ride and see if the engine runs smooth thru the whole RPM range, if it hesitates on the low end go up one thousands to Drill#67(0.320) and keep going up one at a time until the engine runs smooth thru the whoe rpm range. Then when it feels good riding it - the spark plug will tell you when it is perfect by looking for a light brown to grey color on the electrode. Black and sooty sometimes wet=too rich. Hope this helps
................quarkdude

Thanks quarkdude,
I will go online now and buy one of there drill sets. I hated using the file method but I couldnt wait. I figure I have 2 options if I went to big with the file I will follow your instructions for resoldering the hole and starting over or Ill pick up another set of jets. I do have a couple other motors here now since Im now selling the 70cc 2 stroke kits so I can always pull the jets from another carb if need be till I get the new parts In. This information has been vey helpful. Im trying to learn as much as I can about these kits and do my own experimenting before I get out there and start really promoting these kits. I would hate more then anything if I had a customer calling me saying we just bought one of your motors and they dont run worth a ---- well you know what im saying and I didnt have anyway of offering them help. Thanks again.
 


Q

quarkdude

Guest
The link I just left in my last post they are about 7.00 cheaper once you include the price of shipping. I bought this kit. http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXFJX5&P=7 with this pin vise http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXNU71&P=ML cost me $20.77 shipped. The other site was 27.00 shipped
Hello Mogyver69,

Wow, that is a really really good price for the drill bits and the pin vice. Here is Albuquerque we have a place called Santa Fe Tool and we have a Harbor Freight the best of the best of Chinese all the way. I put together a drill and pin vice set from both of those places. I had to drive all over town to get the parts so I probably spent more in gas then you did in shipping. ha ha.:???:
The link you found looks really good. Drill bits from #61-80, perfect. What a price to. Good internet find. You bike is as good as tuned already.
Take care, and can't wait to hear that you got it tuned.
....................quarkdude - Albuquerque, NM
 
L

Large Filipino

Guest
I know were talking small here and a regular digital camera's not gonna cut it,but if by chance you have a digital SLR camera,can you take pics?
 
L

Large Filipino

Guest
Well when you do the actual sodering and redrilling it would be cool to see that. I know that's asking a lot from Quarkdude cause he's not gonna do this all over again,but anything you haven't done yet,that would be cool if the rest of us can see.
Frankly,most of us here won't touch this with a ten foot pole.
Like for example,I'm assuming the needle with the hole is solid and not hollow? Sodering takes not even a drop? And how exactly do you make it all smooth?
 
M

Mogyver69

Guest
Well when you do the actual sodering and redrilling it would be cool to see that. I know that's asking a lot from Quarkdude cause he's not gonna do this all over again,but anything you haven't done yet,that would be cool if the rest of us can see.
Frankly,most of us here won't touch this with a ten foot pole.
Like for example,I'm assuming the needle with the hole is solid and not hollow? Sodering takes not even a drop? And how exactly do you make it all smooth?
I think your alittle confused. The needle is solid. You dont do any soldering on it. Theres a jet inside the bowl area. If your looking from the top where the needle enters this is not the actual hole you are soldering. On the other end of that hole inside the bowl is a jet. It is removable and can be made larger by drilling the hole bigger with the special drill bits Quarkdude and myself have been discussing back and forth. I will take some pics for you maybe this evening of the iternal parts and post them for you so you can see.
 
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