Motorized Bicycle Carburetor pictures how to install and rebuild

BikeBerry.com

Dealer
Nov 7, 2008
38
0
6
California
www.bikeberry.com
Re: Carb pictures how to

I wanted you to see the IDLE SCREW and the little throttle slide guide and the fuel tickler, push it down for a few seconds and it lets fuel in the carb for a cold start along with using the choke. I don't use it myself.( the tickler)
when you go to put the slide back into the carb make sure, I mean damn sure you put the slide in the carb matching the long slot of the slide with with the small pin in the carb (aka. the slide guide0 it is on the opposite side of the idle screw. Look it over closely work the throttle twist grip while looking into the throat of the carb(air cleaner off ) making sure the throttle slide closes all the way and opens all the way. If you don't do this step you might get a "Mr. toads wild ride' the first time you fire up your bike. YOU DO HAVE THE KILL SWITCH HOOKED UP RIGHT? Good for you now letsw continue with tearing this unpolished turd up.


I have the idle screw label inside as idle speed tit in slide body. It should be just the tip of the idle speed screw. the idle speed screw works on the short notch of the throttle slide holding the slide open just enough for the engine to idle when you get the idle speed screw adjusted to your liking, the slides short notch is angled for the idle speed rounded off end to sit against as you turn in the idle speed the rounded end pushes against the angled notch making the slide open up a little for the proper idle. How fast it idles depends on you or what you like for an idle speed. If your running lights then you might want a faster idle if it dies when your light are turned on .
I really like how not only are you taking pics of everything, you have them on a white board and breaking down everything! your efforts are super awesome and really helpful! Keep being great!.trlrl.
 

bikenovice

New Member
Aug 20, 2012
1
0
0
Walnut Creek, CA
Great explanation but my engine won't start. I have gas, a good spark but after trying to start and immediately removing the spark plug it seems rather dry; like the fuel is not getting to the cylinder. The carburator jet seems clear and there is fuel in the bowl (maybe not enough?). It seems like the engine tries to start when I pop the clutch and tries harder when I open the throttle, even wide opened it tries a little harder while I'm pedaling like crazy but it quits when I stop pedaling. HELP.
 

tooljunkie

Member
Apr 4, 2012
663
4
16
Manitoba,Canada
firstly,bikenovice welcome to the site.
second,please take a look at forum rules and introduce yourself as requested by the moderator(s).
it is always helpful to mention the type of engine you are running,as well as carb type/model so we can give you useful advice.

carb may have dirt lodged in the main jet,preventing fuel from travelling up the venturi.
choke lever(if its the carb im thinking of) should be up for a cold start,and down as soon as it fires.
going to need more info before we can go any further.
new build,or old build and been sitting....
 

tooljunkie

Member
Apr 4, 2012
663
4
16
Manitoba,Canada
carb cleaning:

i just tried soda blasting a carb.i'm amazed at the speed and the results an inexpensive portable sandblaster filled with baking soda will achieve.
here's the one i used,i bought it when it came on sale.http://www.princessauto.com/pal/pro...rs/18-oz.-Hopper-Gravity-Feed-Sandblaster-Gun

should have taken photos,it was a honda carb,gooey and sitting for three years.
it cleaned the jet spotless in seconds.used about 50 cents in soda to clean whole carb.
dust mask and do it outside.
awesome awesome.
 

JonnyR

New Member
May 13, 2012
1,203
0
0
33
ronkonkoma, new york
Re: Carb pictures how to

bang its apart. My dry board doesn't have spell check and my penmanship needs work.

some one needs to make s spell checking white board what dosent get eaten by fuel for these sort of tutorials its a nice job though teaching the inner workings of the carb on these now you just need to post how to make the stupid CNS and cable choke NT work good
 
Last edited:

Huffydavidson

STREETRACER/MANUFACTURER
Jan 29, 2012
1,076
4
38
st.louis,mo.
The solution is throw the CNS in the recycle bin because that's all it's good for . Then go by yourself a RT from DAX.com . The CNS is a over jetted air leaking untunable mystery carburetor .CNS is what it says it is . "C"an "N"ot"S"service carb.
 
Jan 13, 2011
47
0
6
WEST MIFFLIN PA
It works fine and idles nice even without the governor on it. I would have kept the governor on it but the elbow 90 degree bend I used on the intake manifold made it a rather difficult task if I were to try. One thought was to use electronic sensors and servo motors to make the connection as they go around corners without bending....... part of quote by measure twice

That seemed to be a LONG ramble without relevance to the thread. All about 4 stokes, governors, ect. This is concerning the basic 2 stroke carb.

You do seem to know what your talking about though, just misplaced maybe. I was confused.
 
Last edited:

MEASURE TWICE

Well-Known Member
Jul 13, 2010
2,353
338
83
CA
It works fine and idles nice even without the governor on it. I would have kept the governor on it but the elbow 90 degree bend I used on the intake manifold made it a rather difficult task if I were to try. One thought was to use electronic sensors and servo motors to make the connection as they go around corners without bending....... part of quote by measure twice

That seemed to be a LONG ramble without relevance to the thread. All about 4 stokes, governors, ect. This is concerning the basic 2 stroke carb.

You do seem to know what your talking about though, just misplaced maybe. I was confused.
========================================

Question moved to new thread of mine, sorry!

removed and moved to http://motorbicycling.com/showthread.php?p=446651#post446651

MT
 

Dogtown Burner

New Member
Sep 15, 2011
349
2
0
Los Angeles
The solution is throw the CNS in the recycle bin because that's all it's good for . Then go by yourself a RT from DAX.com . The CNS is a over jetted air leaking untunable mystery carburetor .CNS is what it says it is . "C"an "N"ot"S"service carb.
must say I got a good giggle on your CNS description. (not the last bit) I agree, and the most ridiculous is the non adjustable needle. i mean, really?! oh wait, and the claims by vendors "racing carb"!!!
Now, one thing i did find- I bored out a cylinder to the physical limitation of the cylinder. I added a huge pipe (KX 65) and I found that the super rich CNS actually helped reduce the ridiculously lean condition i had created. I only used it for a minute because I flat out didnt want all the cables and the lack of adjustability. I am going to try this PW 50 idea, although fyi we have been using mikuni 18mm carbs for our racers. "dream carb". makes the bike like a kx-60. although not for the carburetor theory & tuning inclined. overly adjustable, with a fair amount of balance when making a jet adjustment. it is unique in that the pilot jet is always in play, so it affects the mixture curve throughout the rpm curve. anyway, sorry for the ramble I'm not awake, but get a mikuni if you want real power and performance fellas.
 

nikymor

New Member
Dec 30, 2012
16
0
0
philippines
has anyone tried putting a fuel pump for ht 49cc engines? what size of carb is best used for the china 49cc engine? a 21mm or a 22mm? im from the philippines and i just recently bought a bike engine kit,havent started yet on the build because tha bike shops here are still closed, although ive been compiling stuff here so when im all set il be doing the tips ive gathered here and post some screenies.which some topics lack, so il just link them up ^^ for newbies like me,thanks in advance more power god bless
 
Last edited:
Jun 29, 2020
6
5
3
60
Westerly Rhode Island
Hi, Mat from R.I. here, already did the obligatory introduction. Lotsa great stuff regarding NT Carbs...got any info on HP Carbs? Got the Zeda 66/80cc freshly broke-in, and swapped the NT for an HP, and at first was having some issues with it that were my complete lack of knowledge regarding needle-less carbs, but I did manage to get the bike to run with it, now to get it to idle on it's own. I'm told that's a magical combination of cable/idle screw adjustment(s)? There is a considerable amount of slack in the cable. I did swap the stock piece at the lid for the NT piece, as was recommended by several videos regarding them, but absolutely no information on how to adjust idle in these things. I'm pretty certain it's something I'm overlooking, just can't decide what...